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Gigantic Iceberg Disintegrates as Concern Grows Over Glacier Stability, Sea Level Rise

The stability of a key Antarctic glacier appears to have taken a turn for the worse as a large iceberg that broke off during September has swiftly shattered. Meanwhile, scientists are concerned that the rate of sea level rise could further accelerate in a world forced to rapidly warm by human fossil fuel burning.

(Iceberg drifting away from the Pine Island Glacier rapidly shatters. Image source: European Space Agency.)

This week, a large iceberg that recently calved from West Antarctica’s Pine Island Glacier rapidly and unexpectedly disintegrated as it drifted away from the frozen continent. The iceberg, which covers 103 square miles, was predicted to drift out into the Southern Ocean before breaking up. But just a little more than two months after calving in September, the massive chunk of ice is already falling apart.

The break-off and disintegration of this large berg has caused Pine Island Glacier’s ice front to significantly retreat. From 1947 up until about 2015, the glacier’s leading edge had remained relatively stable despite significant thinning as warmer water began to cut beneath it. But since 2015, this key West Antarctic glacier has begun to rapidly withdraw. And it now dumps 45 billion tons of ice into the world ocean each year.

(Glaciers like Pine Island balance on a geological razor’s edge. Because they sit on a reverse slope, it only takes a relatively moderate amount of ocean warming to precipitate a rapid collapse. These collapses have happened numerous times in the past when the Earth warmed. Now, human-forced climate change is driving a similar process that is threatening the world’s coastal cities. Image source: Antarctic Glaciers.)

The present rate of melt is enough to raise sea levels by around 1 millimeter per year. That’s not too alarming. But there’s concern that Pine Island Glacier will speed up, dump more ice into the ocean and lift seas by a faster and faster rate.

Pine Island Glacier and its sister glacier Thwaites together contain enough water to raise seas by around 3-7 feet. The glacier sits on a reverse slope that allows more water to flood inland, exposing higher and less stable ice cliffs as the glacier melts inland. If the glacier melts too far back and the ice cliffs grow too high, they could rapidly collapse — spilling a very large volume of ice into the ocean over a rather brief period of time. As a result, scientists are very concerned that Pine Island could swiftly destabilize and push the world’s oceans significantly higher during the coming years and decades.

No one is presently predicting an immediate catastrophe coming from the melt of glaciers like Pine Island. However, though seemingly stable and slow moving, glacial stability can change quite rapidly. Already, sea level rise due to melt from places like Greenland and Antarctica is threatening many low-lying communities and nations around the world. So the issue is one of present and growing crisis. And there is very real risk that the next few decades could see considerable further acceleration of Antarctica’s glaciers as a result of human-forced warming due to fossil fuel burning.

Dr Robert Larter, a marine geophysicist at British Antarctic Survey, who has researched Pine Island Glacier in his work with the Alfred Wegener Institute, recently noted to Phys.org:

“If the ice shelf continues to thin and the ice front continues to retreat, its buttressing effect on PIG will diminish, which is likely to lead to further dynamic thinning and retreat of the glacier. PIG already makes the largest contribution to  of any single Antarctic glacier and the fact that its bed increases in depth upstream for more than 200 km means there is the possibility of runway retreat that would result in an even bigger contribution to sea level.”

CREDITS:

Hat tip to Colorado Bob

Hat tip to Erik Friedrickson

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The Present Threat to Coastal Cities From Antarctic and Greenland Melt

Seas around the world are rising now at a rate of about 3.3 millimeters per year. This rate of rise is faster than at any time in the last 2,800 years. It’s accelerating. And already the impacts are being felt in the world’s most vulnerable coastal regions.

(Rates of global sea level rise continue to quicken. This has resulted in worsening tidal flooding for coastal cities like Miami, Charleston, New Orleans and Virginia Beach. Image source: Ice Melt, Sea Level Rise, and Superstorms.)

Sea Level Rise and Worsening Extreme Rainfall are Already Causing Serious Problems

Last week, New Orleans saw pumps fail as a heavy thunderstorm inundated the city. This caused both serious concern and consternation among residents. Begging the question — if New Orleans pumps can’t handle the nascient variety of more powerful thunderstorms in the age of human-caused climate change, then what happens when a hurricane barrels in? The pumps, designed to handle 1.5 inch per hour rainfall amounts in the first hour and 1 inch per hour rainfall amounts thereafter were greatly over-matched when sections of the city received more than 2 inches of rainfall per hour over multiple hours.

Higher rates of precipitation from thunderstorms are becoming a more common event the world over as the hydrological cycle is amped up by the more than 1 degree Celsius of temperature increase that has already occurred since 1880. And when these heavy rainfall amounts hit coastal cities that are already facing rising seas, then pumps and drainage systems can be stressed well beyond their original design limits. The result, inevitably, is more flooding.

(Dr Eric Rignot, one of the world’s foremost glacial scientists, discusses the potential for multimeter sea level rise due to presently projected levels of warming in the range of 1.5 to 2 C by mid to late Century.)

New Orleans itself is already below sea level. And the land there is steadily subsiding into the Gulf of Mexico. Add sea level rise and worsening storms on top of that trend and the crisis New Orleans faces is greatly amplified.

All up and down the U.S. East and Gulf Coasts, climate change driven sea level rise and a weakening Gulf Stream are combining with other natural factors that can seriously amplify an ever-worsening trend toward more tidal flooding. It’s a situation that will continue to worsen as global rates of sea level rise keep ramping higher. And how fast seas rise will depend both on the amount of carbon that human beings ultimately dump into the Earth’s atmosphere and on how rapidly various glacial systems around the world respond to that insult (see discussion by Dr. Eric Rignot above).

Presently High and Rising Atmospheric Carbon Levels Imply Ultimately Catastrophic Sea Level Rise — How Soon? How Fast? Can We Mitigate Swiftly Enough to Prevent the Worst?

Presently, atmospheric carbon forcing is in the range of 490 parts per million CO2 equivalent. This heat forcing, using paleoclimate proxies from 5 to 30 million years ago, implies approximately 2 degrees Celsius of warming this Century and about 4 degrees Celsisus of warming long term. It also implies an ultimate sea level rise of between 60 and 180 feet over the long term. In other words, if atmospheric carbon levels are similar to those seen during the Miocene, then temperatures are also ultimately headed for those ranges. Soon to be followed by a similar range of sea level rise. In the nearer term, 1.5 to 2 C warming from the 2030s to late Century is enough to result in 20 to 30 feet of sea level rise.

Of course, various climate change mitigation actions could ultimately reduce that larger heat forcing and final related loss of glacial ice. But with carbon still accumulating in the atmosphere and with Trump and other politicians around the world seeking to slow or sabotage a transition away from fossil fuels, then it goes to follow that enacting such an aggressive mitigation will be very difficult to manage without an overwhelming resistance to such harmful policy stances.

(Antarctic ice loss through 2016. Video source: NASA.)

That said, warming and related sea level rise will tend to take some time to elapse. And the real question on many scientists’ minds is — how fast? Presently, we do see serious signs of glacial destabilization in both Greenland and West Antartica. These two very large piles of ice alone could contribute 34 feet of sea level rise if both were to melt entirely.

Meanwhile, East Antarctica has also recently shown some signs of movement toward glacial destabilization. Especially in the region of the Totten Glacier and the Cook Ice Shelf. But rates of progress toward glacial destabilization in these zones has, thus far, been slower than that seen in Greenland and West Antarctica. Present mass loss hot spots are in the area of the Thwaites Glacier of West Antarctica and around the western and southern margins of Greenland.

(Greenland ice loss through 2016. Video source: NASA.)

With global temperatures now exceeding 1 C and with these temperatures likely to exceed 1.5 C within the next two decades, it is certain that broader heat-based stresses to these various glacial systems will increase. And we are likely to see coincident melt rate acceleration as more glaciers become less stable. The result is that coastal flooding conditions will tend to follow a worsening trend — with the most vulnerable regions like the U.S. Gulf and East Coasts feeling the impact first. Unfortunately, there is risk that this trend will include the sudden acceleration of various glaciers into the ocean, which will coincide with rapid increases in global rates of sea level rise. In other words, the trend for sea level rise is less likely to be smooth and more likely to include a number of melt pulse spikes.

Such an overall trend including outlier risks paints a relatively rough picture for coastal city planners in the 1-3 decade timeframe. But on the multi-decade horizon there is a rising risk that sudden glacial destabilization — first in Greenland and West Antarctica and later in East Antarctica will put an increasing number of coastal cities permanently under water.

Rapid Mitigation Required to Reduce Risks

The only way to lower this risk is to rapidly reduce to zero the amount of carbon hitting the atmosphere from human sources while ultimately learning how to pull carbon out of the atmosphere. The present most rapid pathway for carbon emissions reductions involves an urgent build-out of renewable and non-carbon based energy systems to replace all fossil fuels with a focus on wind, solar, and electrical vehicle economies of scale and production chains. Added to various drives for sustainable cities and increasing efficiency, such a push could achieve an 80 percent or greater reduction in carbon emissions on the 2-3 decade timescale with net negative carbon emissions by mid Century. For cities on the coast, choosing whether or not to support such a set of actions is ultimately an existential one.

Links:

Fragmenting Prospects For Avoiding 2 C Warming

NASA Antarctic Ice Loss

Scientists Just Uncovered Another Troubling Fact About Antarctica’s Melting Ice

It Wasn’t Even a Hurricane, But Heavy Rains Flooded New Orleans as Pumps Faltered

Why Seas are Rising Faster in Miami

Miocene Relative Sea Level

Temperature on Planet Earth

Ice Melt, Sea Level Rise, and Superstorms

New Crack Found in Delaware-Sized Chunk of Larsen C Ice Shelf as it Heads Toward Southern Ocean

A 2,000 square mile section of the Larsen C Ice Shelf is hanging by a thread as it continues to drift toward the Weddell Sea.

(A second crack develops in Larsen C Ice Shelf. Image source: Project MIDAS.)

The break-off section represents fully 10 percent of all the ice contained in the Larsen C system. It has been divided from the larger ice shelf by a 180 kilometer long crack that began to develop in 2009 and that swiftly lengthened during recent years. Now only a 10 kilometer wide bridge links the breaking section to the larger ice shelf. And considering the enormous stresses now being placed on this break-off section it is expected to go at any time.

Since January, according to researchers at Project MIDAS, the large crack has been widening but its length growth has stalled. However, recent reports out this week from MIDAS found that a new crack had developed at the ice-bridge end of the break-off section. The new crack appears to be rounding the corner of the bridge to begin a quicker path to segmenting the massive ice berg away from Larsen C. A testament to the powerful forces that are inevitably forcing this enormous section of ice to relinquish its hold.

(Large section of Larsen C is moving far faster than the rest of the ice shelf toward the Southern Ocean. Image source: Project MIDAS.)

At issue is the fact that the break-off section is moving toward the Weddell Sea considerably faster than the rest of the Larsen C ice shelf. Much of this large section of ice is proceeding away from the Antarctic mainland at 3 meters per day. Surrounding sections of Larsen C are moving at only 1-2 meters per day. As a result, the toe end of the break-off mass is tipping out into Weddell’s waters and the crack separating it from Larsen C is widening.

It’s not really a question of if this massive block of ice will separate from Larsen C. More an issue of how soon.

Loss of so large a section of ice from Larsen C threatens the entire ice shelf’s stability. And some scientists are questioning whether the whole ice shelf will destabilize and eventually splinter — as happened to Larsen A and Larsen B during recent years.

(Rapid loss of buttressing ice shelves like Larsen C lock in higher and higher ranges for sea level rise. A worrying risk for rapid sea level rise occurs as global temperatures warm to between 1.5 and 2.5 C. A level we are fast approaching. Scientists like James Hansen identify a significant risk for multi-meter sea level rise this Century if 2 C warming thresholds are breached. Video Source: Carbon Freeze.)

Warming ocean waters due to human-forced climate change are the primary driver for loss of ice shelves around the world. These ice shelves hold back land glaciers — preventing them from more rapidly sliding into the world’s oceans. Larsen C alone holds back glaciers capable of lifting global ocean levels by 4 inches. But there are numerous such ice shelves and many are now facing thinning and increasing instability due to warming ocean waters. As a result, a growing number of scientists are concerned about the possibility for multi-meter sea level rise this Century if fossil fuel burning is not swiftly halted.

Links:

Project MIDAS

Carbon Freeze

Second Giant Crack Appears on Larsen C

Crack in Larsen C Forks

Larsen C Destabilization Could Trigger 4 Inch Sea Level Rise

Hat tip to June

Hat tip to Andy in San Diego

Antarctica is About to Lose a 2,000 Square Mile Chunk of Ice — And it Could Mean the End of the Larsen C Ice Shelf

It’s happened before. Ice shelves on the northern Antarctic Peninsula released large chunks of ice into the Southern Ocean as the world warmed up. They developed a concave shape which became unstable. Then they collapsed.

The ultimate collapse of Larsen A occurred in 1995. In 2002, further up the Antarctic Peninsula, the larger Larsen B Ice Shelf succumbed to the same fate. And it is thought that such losses haven’t happened to this section of Antarctica in at least 11,000 years and possibly as long ago as 100,000 years.

(NASA’s Jet Propulsion Laboratory provides this narrative describing the collapse of the Larsen B Ice Shelf in 2002. Video source: JPL.)

But in the present world, one where human fossil fuel emissions have forced global temperatures above 1 C hotter than 1880s averages, the stability of many of the great great ice shelves is now endangered.

Larsen C Ice Shelf to Calve 2,000 Square Mile Ice Berg

Today, a huge rift has nearly bisected a large frontal section of the Larsen C Ice shelf — an ice system many times the size of its now deceased companions Larsen A and Larsen B. And during December — a period when Antarctica was warming into Austral Summer — this massive crack grew by 18 kilometers.

When, and not if, the crack reaches the ocean, a 2,000 square mile ice berg will float away from Larsen C. It will be one of the largest ice bergs ever to form in human memory. One the size of the state of Delaware. It will tower hundreds of feet above the ocean surface. And it will last for years before ultimately melting.

larsen-c-ice-rift-length-and-width

(The Larsen C is rift grew considerably — both lengthening and widening during December of 2016. It was an indication that a massive ice berg was about to break off. Image source: MIDAS.)

This event will change the geography of our world. And for this alteration alone, it has great consequence. But, as Chris Mooney notes in this excellent Washington Post article on the subject, it’s what happens afterward that really counts.

Event Could Presage Total Collapse

Of concern is the fact that once this massive ice berg calves off of Larsen C, the great ice sheet may become unstable. It will take on a concave form. This form will make it more vulnerable to further melt by warming waters running in toward the shelf. Furthermore, the large ice berg will take a chunk of Larsen C’s compressive arch with it. Such a compressive arch — like the arch of a flying buttress — helps to bear the weight of the shelf and keep it from smashing into thousands of tiny pieces. If too much of the arc is lost, the shelf can’t survive for long.

larsen-c-ice-rift-midas

(Researchers at The MIDAS Project have projected that a 2,000 square mile section of the Larsen C Ice Shelf is about to break off. This section represents 10 percent of the Larsen C system. Its loss risks destabilization of the entire ice shelf. If Larsen C does disintegrate, it will release glaciers capable of increasing global sea level by another 4 inches. Image source: MIDAS.)

Glaciologist Eric Rignot notes in The Washington Post:

“We studied the current rift in the past few years, it has been progressing rather ‘normally,’ the recent acceleration in the rift progression is ‘expected’ in my opinion. The consequences on the rest of the ice shelf are not clear at this point. If the calving continues and goes past the compressive arch … then the ice shelf will break up.”

Scientists are currently divided over the issue of whether or not Larsen C’s near-term demise is imminent. However, the loss of such a massive ice berg from Larsen C, the present human-forced warming of the Antarctic land and ocean environment, and the presently observed thinning of the ice shelf all point toward a rising risk of destabilization or disintegration.

As with most things geological, you can’t really say that such an event is certain until after the fact. But as for Larsen C’s prospects of long term survival, things aren’t looking too great at the moment.

Links/Credits

The MIDAS Project

Antarctica is Set to Lose an Enormous Piece of Ice

An Ice Berg the Size of Delaware is About to Break off From Antarctica

NASA’s Jet Propulsion Laboratory

Climate Change Has Left Bolivia Crippled by Drought

“Bolivians have to be prepared for the worst.”President Evo Morales.

*****

Like many countries, Bolivia relies on its glaciers and large lakes to supply water during the lean, dry times. But as Bolivia has heated with the rest of the world, those key stores of frozen and liquid water have dwindled and dried up. Warming has turned the country’s second largest lake into a parched bed of hardening soil. This heat has made the country’s largest lake a shadow of its former expanse and depth. It has forced Bolivia’s glaciers into a full retreat up the tips of its northern mountains — reducing the key Chacaltaya glacier to naught. Multiple reservoirs are now bone-dry. And, for hundreds of thousands of people, the only source of drinking water is from trucked-in shipments.

Drought Emergency Declared for Bolivia

After decades of worsening drought and following a strong 2014-2016 El Nino, Bolivia has declared a state of emergency. 125,000 families are under severe water rationing — receiving supplies only once every three days. The water allocation for these families is only enough for drinking. No more. Hundreds of thousands beyond this hardest hit group also suffer from some form of water curtailment. Schools have been closed. Businesses shut down. 60,000 cattle have perished. 149 million dollars in damages have racked up. And across the country, protests have broken out.

The city of La Paz, which is the seat of Bolivia’s government and home to about 800,000 people (circa 2001) has seen its three reservoirs almost completely dry up. The primary water reservior — Ajuan Kota — is at just 1 percent capacity. Two smaller reserviors stand at just 8 percent.

bolivia-drought

(Over the past year, drought in Bolivia has become extreme — sparking declarations of emergency and resulting in water rationing. It is the most recent severe dry period of many to affect the state over the past few decades. President Morales has stated that climate change is the cause. And the science, in large part, agrees with him. Image source: The Global Drought Monitor.)

In nearby El Alto, a city of 650,000 people (circa 2001), residents are also suffering from water shortages. The lack there has spurred unrest — with water officials briefly being held hostage by desperate citizens.

As emergency relief tankers wind through the streets and neighborhoods of La Paz and El Alto, the government has established an emergency water cabinet. Plans to build a more resilient system have been laid. And foreign governments and companies have been asked for assistance. But Bolivia’s larger problem stems from droughts that have been made worse and worse by climate change. And it’s unclear whether new infrastructure to manage water can deal with a situation that increasingly removes the water altogether.

Dried out Lakes, Dwindling Glaciers

Over the years, worsening factors related to climate change have made Bolivia vulnerable to any dry period that may come along. The added effect of warming is that more rain has to fall to make up for the resulting increased rate of evaporation. Meanwhile, glacial retreat means that less water melts and flows into streams and lakes during these hot, dry periods. In the end, this combined water loss creates a situation of drought prevalence for the state. And when a dry period is set off by other climate features — as happened with the strong El Nino that occurred during 2014 to 2016 — droughts in Bolivia become considerably more intense.

Ever since the late 1980s, Bolivia has been struggling through abnormal dry periods related to human caused climate change. Over time, these dry periods inflicted increasing water stress on the state. And despite numerous efforts on the part of Bolivia, the drought impacts have continued to worsen.

bolivia-satellite

(In this NASA satellite shot of northern Bolivia taken on November 6, 2016, we find very thin mountain snow and ice cover in upper center, a lake Titicaca that is both now very low and filled with sand bars at upper left, and a completely dried up lake Poopo at bottom-center. Bolivia relies on these three sources of water. One is gone, and two more have been greatly diminished. Scientists have found that global warming is melting Bolivia’s glaciers and has increased evaporation rates by as much as 200 percent near its key lakes. Image source: LANCE MODIS.)

By 1994, added heat and loss of glaciers resulted in the country’s second largest lake — Poopo — drying up. The lake recovered somewhat in the late 1990s. But by early 2016, a lake that once measured 90 x 32 kilometers at its widest points had again been reduced to little more than a cracked bed littered with abandoned fishing hulls. Scientists researching the region found that the rate of evaporation in the area of lake Poopo had been increased by 200 percent by global warming.

Bolivia’s largest lake — Titicaca — is also under threat. From 2003 to 2010, the lake is reported to have lost 500 square miles of surface water area. During 2015 and 2016 drought near Titicaca intensified. In an act of desperation, the government of Bolivia allocated half a billion dollars to save the lake. But despite this move, the massive reservoir has continued to shrink. Now, the southern section of the lake is almost completely cut off by a sand bar from the north.

In the Andean mountains bordering Bolivia, temperatures have been increasing by 0.6 degrees Celsius each decade. This warming has forced the country’s glaciers into full retreat. In one example, the Chacaltaya glacier, which provided 30 percent of La Paz’s water supply, had disappeared entirely by 2009. But the losses to glaciers overall have been widespread and considerable — not just isolated to Chacaltaya.

Intense Drought Flares, With More to Come

By December, rains are expected to return and provide some relief for Bolivia. El Nino has faded and 2017 shouldn’t be as dry as 2015 or 2016. However, like many regions around the world, the Bolivian highlands are in a multi-year period of drought. And the over-riding factor causing these droughts is not the periodic El Nino, but the longer-term trend of warming that is melting Bolivia’s glaciers and increasing rates of evaporation across its lakes.

In context, the current drought emergency has taken place as global temperatures hit near 1.2 degrees Celsius hotter than 1880s averages. Current and expected future burning of fossil fuels will continue to warm the Earth and add worsening drought stress to places like Bolivia. So this particular emergency water shortage is likely to be just one of many to come. And only an intense effort to reduce fossil fuel emissions can substantially slake the worsening situation for Bolivia and for numerous other drought-affected regions around the world.

Links:

Bolivia Declares National Emergency Amid Drought

Bolivia Schools Close Early as Drought Empties Reservoirs

Is the World Running out of Water? Bolivia Declares National Emergency Due to Drought

Hothouse Turns Bolivia’s Second Largest Lake into Withered Wasteland

The Global Drought Monitor

LANCE MODIS

Climate Hot Map — Chacaltaya Glacier

Hat tip to Colorado Bob

Hat tip to ClimateHawk1

Half a Kilometer of Ice Gone in Just 7 Years — West Antarctica’s Smith Glacier Points To Nightmare Melt Scenario

The nightmare global warming melt scenario for West Antarctica goes something like this —

First, ocean waters warmed by climate change approach the vast frozen continent. Melt already running out from the continent forms a fresh water lens that pushes these warmer waters toward the ocean bottom. The waters then get caught up in currents surrounding Antarctica that draw them in toward numerous submerged glacial faces. The added ocean heat combines with falling melting points at depth to produce rapid melt along sea fronting glacier bases. Since many of these glaciers sit on below sea level beds that slope downward toward the interior of Antarctica, a small amount of initial melt sets off an inland flood of these warmer waters that then produces a cascade of melt. This glacial melt chain reaction ultimately generates a Heinrich Event in which armadas of icebergs burst out from Antarctica — forcing global sea levels to rapidly rise.

This is Why We Worry So Much About Multi-Meter Sea Level Rise

Ultimately, seas rising by multiple meters this Century are a very real possibility under current warming scenarios in which such a series of cascading melt events occurs in West Antarctica.

(NASA video narrated by Dr. Eric Rignot, a prominent glacial scientist. Concerns about the origin of melt water pulse 1A during the end of the last ice age led to investigation of large Antarctic melt pulses as a potential source. Subsequent investigation identified melt vulnerabilities at the bases of large sea fronting glaciers in West Antarctica to present and predicted levels of ocean warming. At issue was the fact that bottom waters were warming and that because many glaciers rested on sea beds that sloped inland, melt rates had the potential to very rapidly accelerate.)

Though such a nightmare melt scenario was recently theoretical, it represented a very real potential near-future event as global temperatures rose into the 1-2 degrees Celsius above 1880s range during recent years. For times in the geological past around 115,000 years ago also produced large glacial melt pulses and related sea level rises of 15-25 feet during periods of similar warmth.

However, direct evidence of such a powerful melt dynamic had not yet been directly observed in Antarctica’s glaciers. Fresh water lenses were developing, rates of glacial loss were quickening. Basal melt rates looked bad. But the kind of tremendous losses necessary to produce rapid sea level rise were not yet fully in evidence.

Smith Glacier Loses Half a Kilometer of Ice in Seven Years

That situation changed during recent weeks when two scientific papers broke the news that some of West Antarctica’s glaciers had lost upwards of a half a kilometer of ice thickness due to contact with warm ocean waters over the past decade.

The studies, entitled Rapid Submarine Ice Melting in the Grounding Zones of Ice Shelves in West Antarctica and Grounding Line Retreat of Pope, Smith and Kohler Glaciers took a comprehensive look at both surface and underside melt of three major west Antarctic glaciers near the Thwaites and Pine Island Glacier systems. These glaciers included Pope, Smith and Kohler — which have seen increasing instability and rates of seaward movement during recent years. Using multiple instruments, the scientists found evidence of massive ice losses and speeding ice flows.

pope-smith-and-kholer-glacial-flow-velocities

(Surface velocity of Kohler, Smith and Pope Glaciers provided by NASA. More rapid seaward movement of glaciers = faster rates of sea level rise.)

The losses occurred at a time when an influx of warmer water (warming circumpolar deep water) was heating the ice shelves and grounding lines buttressing these three partially submerged glaciers. This warming was found to have produced melt along the grounding zones of these glaciers in the range of 300 to 490 meters from 2002 to 2009. In other words, about 1/3 to 1/2 a kilometer of ice thickness at the grounding line was lost in just seven years. Melted away from below by warming deep ocean conditions at the rate of up to 70 meters or around 230 feet per annum.

The studies found that the Pope and Kohler glaciers, which rested on up-sloping sea beds, produced slower rates of melt. While Smith, which sat on a retrograde (or down-sloping bed) produced very rapid rates of melt. According to the Nature study:

We attribute the different evolution of Smith Glacier to the retreat of its grounding line deeper allowing warmer waters to flood its grounding zone, and increasing ocean thermal forcing due to the lowering of the in situ melting point; as well as to the exposure of the glacier bottom to ocean water as the grounding line retreated rapidly.

A Context of Worsening Risks

Unfortunately, numerous glaciers in the Amundsen Sea region including parts of the Thwaites system and the massive Pine Island Glacier also sit on retrograde slopes. These glaciers are seeing increasing fluxes of warm, deep water. By themselves they represent multiple feet of sea level rise (4-7 feet). Furthermore, Thwaites and Pine Island Glacier currently buttress a number of massive inland glaciers that become vulnerable to melt if inland-running retrograde slopes become flooded with warming ocean waters.

The very real concern is that Smith Glacier serves as a harbinger for near future events to come. As a result, coastal regions around the world are now under a heightened risk of swiftly rising seas and rapid coastal inundation over the coming years and decades.

Links:

Rapid Submarine Ice Melting in the Grounding Zones of Ice Shelves in West Antarctica

Grounding Line Retreat of Pope, Smith and Kholer Glaciers

Heinrich Event

Dr. Eric Rignot

Studies Offer Glimpse of Melting Under Antarctic Glaciers

Thwaites Glacier

Pine Island Glacier

Hat tip to Zack Labe

Hat tip to Miles h

“We Have Nowhere to Go” — Sea Level Rise is Devouring the Coast of West Africa

“I am very afraid for the future of this place. Sooner or later we will have to leave, but we have nowhere to go.” — Buabasah a resident of Fuvemeh, a West African town being swallowed by the sea as reported by Matteo Fagotto.

*****

A new, must read, report out in Foreign Policy by Matteo Fagotto highlights a widespread ongoing disruption due to sea level rise to the vulnerable coastal region of West Africa. And, for years now, scientists at the IPCC have been warning that just such an event could occur.

The coastal zone of West Africa stretches for 4,000 miles from Mauritania to the Congo. It includes highly populated regions surrounding low elevation cities and towns in such African nations as Gabon, Nigeria, Senegal, Guinea, The Ivory Coast, Sierra Leone, Cameroon, Liberia, and Ghana. Most industrial activity and food-growing is located near the coast of these nations — accounting for 56 percent of GDP for the region according to the World Bank. And coastal population concentrations in regions vulnerable to sea level rise are very high. In all about 31 percent of the 245 million people dwelling in West Africa live in this fragile land.

global-sea-level-rise

(Due to global warming and glacial melt spurred by fossil fuel burning, oceans are now rising at their fastest rates in 10,000 years. As a result, many coastal towns and cities around the world are under increasing threat of flooding. In West Africa, a recent report by Foreign Policy paints a picture of broadening inundation. Unfortunately, current rates of ocean rise are far slower than what human-caused climate change may set off over the coming decades. Image source: AVISO.)

Most of the coastline features a lagoonal geography that is very low-lying. Meanwhile, funds for coastal defenses like planting mangrove forests and pumping in sand to re-nourish beaches are difficult to procure. As a result, these large cities and population centers are highly vulnerable to impacts from human-forced climate change related to sea level rise.

The Great Flooding Begins

Ever since the early 1990s, scientific reports have highlighted the vulnerability of West Africa to inundation, flooding and loss of key industries, food growing and infrastructure due to glacial melt, thermal expansion of ocean waters set off by warming, and an increase in storm strength in the North Atlantic. All impacts that scientists feared would be coming due to a human-forced warming of the world. Now, just such an inundation and loss appears to be underway.

According to the recent report out in Foreign Policy, and according to other eyewitness accounts and news reports coming in from coastal West Africa during recent years, sea level rise and increasing erosion due to powerful storms continue to produce worsening impacts for the region. In one of the most glaring instances, the swelling surf is now in the process of destroying a Ghana fishing village (Fuvemeh) that recently housed 2,500 people. Homes, coconut plantations, and fishing wharfs have all been taken by the seas and swirling sands. But Fuvemeh is just one of thousands of like communities now confronting an onrush of waves that each year bites off as much as 80-120 feet of coastline.

(House destroyed by waves in Fuvemeh, Ghana. Sadly, sea level rise related impacts like this are now being seen all up and down West Africa’s 4,000 mile long coastline.)

Moreover, Foreigh Policy finds that megacities like Lagos (population 5.6 million) and large cities like Accra (population 1.6 million) are increasingly threatened by the encroaching waters. In Accra, the rainy season now causes an annual inundation of sections of the city — a new impact that resulted in 25 people losing their lives last year. Nouakchott, the capital of Mauritania and home to approximately 1 million people, now sees the loss of 80 feet of coastline along its Atlantic shore every year. Meanwhile, parts of Togo lost 118 feet of shore line last year alone. Along the coast from Gambia to Senegal and including communities like Cotonou and Lome, growing numbers of houses, hotels, restaurants, roads, and even water treatment plants are now little more than washed out husks and crumbling bits of infrastructure — lapped by a rising tide.

Heartbreak, Loss of Homes, Dislocation

As the waters rise, residents are forced to move inland. Younger, more mobile residents have often fled the region entirely. Others have rebuilt their homes further inland only to have them flooded again. Ocean productivity is on the decline in the region. Fish and other animals that supported coastal industries have migrated northward or succumbed to worsening ocean conditions. The combined losses have produced economic hardships as coastal cities see increasing gang activity, drug use, theft and violence.

Overall, the United Nations estimates that 5-10 percent of West Africa’s GDP will ultimately be lost due to impacts related to sea level rise. And the recent report by Foreign Policy points to growing evidence that the crisis is starting now. But the ever-more-human toll is nothing less than heart-wrenching.

West Africa Just One of Many Vulnerable Regions

Reports by Foreign Policy and others on the plight of coastal West Africa shines a light on sea level rise related hardships and losses throughout that region. However, numerous low-lying stretches of coastline are now facing similar problems. Bangladesh is currently seeing a wave of mass migration inland due to sea level rise related flooding. The Mi Cong Delta region is seeing its rice farms threatened by an influx of salt water. The Indus River Delta region in Pakistan is also experiencing mass migration away from coastlines. Coastal Pacific Islands are facing an existential threat due to sea level rise now. And the U.S. East Coast and Gulf Coasts are facing their own problems from worsening storm surge flooding and more widespread nuisance flooding due to sea level rise. So what we’re seeing in West Africa is part of a much larger overall global context.

Links:

West Africa is Being Swallowed by the Sea

West Africa Map

AVISO Sea Level Rise

IPCC: The Regional Impacts of Climate Change

Ghana’s Coastal Erosion — The Village Buried in Sand

Ghana Accra Floods

How The World’s Oceans Could be Running out of Fish

Drugs and Crime Mobilise International Support For West Africa Coast Initiative

Hat tip to Colorado Bob

Hat tip to Wili

Climate Change — Seas Are Now So High it Only Takes a King Tide to Flood the US East Coast

“It gets higher every year. I imagine it will be worse next year.” Guido Pena, Miami marina employee commenting on water levels during king tides.

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King tide. It’s a new term for an old phenomena. One that few people noticed before human-forced climate change began to push the world’s oceans higher and higher.

During spring and fall, the sun lines up with the moon and other astronomical bodies to produce a stronger gravitational pull on the Earth. This pull, in its turn, affects the tides — generating higher and lower tides over certain regions of the world.

(Rising ocean levels due to human-forced climate change is resulting in worsening instances of tidal flooding at times of high tide. In this video, a simple seasonal high tide is enough to flood major roads in Fort Lauderdale on October 17.)

King Tides — Turned into Flooding Events by Climate Change

During past years, these events were called astronomical high and low tides. They weren’t typically a news item because such tides often did not produce flooding. Past construction had placed buildings and key infrastructure above the typical annual range of even the astronomical high tides.

However, during the past century and, ever more-so during recent years, seas have been rising more and more rapidly due to human-caused climate change. A warming of the Earth due to fossil fuel burning that has melted glacial ice — flooding the oceans and causing its waters to thermally expand. As a result, parts of the U.S. East Coast now see ocean levels that are 1.5 feet or more higher than they were at the start of the 20th Century.

This rise, though modest compared to what will happen if global temperatures and greenhouse gas levels remain at currently elevated levels or continue to ramp higher, is now enough to turn astronomical high tides into a notable flooding event. An event that we have begun to call a king tide.

miami-sea-level-trend

(In places like Miami along the US East Coast, sea levels are rising at a swifter and swifter rate due to human-caused climate change. Note the acceleration in the rate of water rise since 2008 indicated in the above graph. Image source: FSU.)

A Climate Change Enabled Tidal Flooding Event Impacting Most of the U.S. East Coast

And over the past few days, from Florida to Boston, the US East Coast has been feeling the effects of just such a climate change caused sea level rise. In Florida, a debate between climate change denier republican Marco Rubio and his democratic opponent Patrick Murphy was held at a site where the local street was flooding due to salt water incursion. Murphy, responding to his opponent’s doubts that seas were actually rising stated:

“Look out your window, right? There’s two or three inches of saltwater on the roads right now. They were not built underwater. Go down to the Florida Keys. The reefs are dying from acidification and bleaching.”

All across Florida, residents were posting pictures on twitter of the rising ocean waters and commenting on the intensification of coastal flooding due to sea level rise during recent years. “It gets higher every year,” said Guido Peña, a Miami Marina employee where the water was shin deep Monday morning, in a statement to the Miami Herald. “I imagine it will be worse next year.”

All up and down the coastline, communities reeling after a raking blow from Hurricane Matthew were again seeing waters rushing up and past the dune line or invading low-lying streets and neighborhoods. But this flooding was due to no hurricane, just the added rise of waters caused by a fossil-fueled warming of the Earth, a melting of her glaciers, and the thermal expansion of her seas.

(King tide flooding enhanced by climate change is now able to completely submerge Long Wharf in Boston.)

In Boston, residents took pictures of a completely submerged Long Wharf yesterday. Mentions of climate change came along with the observations of flooding waters. These included some ominous notes for a future in which scientists are projecting at least another 2 feet of sea level rise for the US East Coast by mid-century (and possibly quite a bit more).

High Vulnerability for U.S. East Coast

Overall, the US East Coast is particularly vulnerable to climate change induced sea level rise. Much of the southeast is subsiding due to crustal rebound following the last ice age which compounds any overall ocean rise. In addition, changes in North Atlantic Ocean currents and wind patterns due to climate change will tend to cause water previously pulled north by the Gulf Stream to rebound against the coastline. An effect that could also add another 1-3 feet of water rise to any baseline total provided by glacial melt and thermal expansion.

Larger news sources like The Weather Channel have provided little context with regards to the impact of climate change on current king tides — simply stating that climate change may affect king tides in the future. However, we should be very clear that without climate change we would not see the flooding from these tides that is now apparent today.

Links:

When the Ocean Rolls onto the Roads, King Tide Sends a Message

What’s a King Tide and Why is it Flooding Boston’s Waterfront?

Marco Rubio Denies Climate Change as King Tides Flood Miami Streets

FSU

Hat tip to Jack Ridley

Hat tip to Greg

Hat tip to DT Lange

Hat tip to Jean Nagy

Hat tip to Ben Kennedy

Record-Hot 2016 Marks the Start of Bad Climate Consequences, Provides “Fierce Urgency” to Halt Worse Harms to Come

“…there is now strong evidence linking specific [extreme] events or an increase in their numbers to the human influence on climate.” — Coumou and Rahmstorf 2012.

“We are confronted with the fierce urgency of now. …We may cry out desperately for time to pause in her passage, but time is deaf to every plea and rushes on. Over the bleached bones and jumbled residues of numerous civilizations are written the pathetic words, ‘Too late.'” — Dr. Martin Luther King, Jr. [emphasis added]

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2016 is on track to be a record-hot year for the history books. Accumulations of heat-trapping gasses in the range of 402 ppm CO2 and 490 ppm CO2e have pushed the global temperature trend into an inexorable upward rise. Meanwhile, increasingly severe climate change-related events ranging from mass coral bleaching, to glacial and sea ice melt, to tree death, to ocean health decline, to the expanding ranges of tropical infectious diseases, to worsening extreme weather events have occurred the world over. This global temperature spike and related ramp-up of extreme events continued throughout a year that is setting up to follow 2014 and 2015 as the third record-hot year in a row.

(2015 saw a substantial jump in global temperatures. 2016 is also on track to hit new record highs. The above graph, by Gavin Schmidt of NASA GISS, provides a vivid illustration of an inexorable warming trend with 2016 as the hottest year yet. According to Gavin, a strong new record for 2016 appears to be a lock. Image source: Climate of Gavin.)

Now, after NASA’s report showing that September 2016 was 1.13 C hotter than 1880s averages (or 0.91 C hotter than NASA’s 20th-century baseline measure), this year is setting up to be the warmest ever recorded by a wide margin. Overall, the first nine months of 2016 have averaged 1.25 C above 1880s temperatures. Meanwhile, the climate year — which runs from December through November — is tracking 1.26 C above 1880s temperatures during the ten-month period of December to September.

2016 as much as 1.25 C Hotter than 1880s Averages

As a result, it appears likely that 2016 will see temperatures in the range of 1.19 C to 1.25 C hotter than 1880s averages. That’s about 0.1 C hotter than 2015 — which is pretty significant considering the fact that the average rate of decadal warming (the rounded rate of global warming every 10 years) has been in the range of 0.15 C since the late 1970s. This year’s temperatures now appear set to exceed 1998’s values by around 0.35 C — or about one-third of the entire warming total seen since large-scale human greenhouse gas emissions began during the late 19th century. This excession should permanently put to rest previous widely circulated false notions that global warming somehow stopped following the strong El Nino year of 1998.

Many responsible sources are now warning that current temperatures are uncomfortably close to two major climate thresholds — 1.5 C global warming and 2.0 C global warming. At the current rate of warming, we appear set to exceed the 1.5 C mark in the annual measure in just one to two decades. Hitting 2 C by or before mid-century has become a very real possibility. Scientists have been urging the global community to avoid 2 C warming before 2100 (and 1.5 C if at all possible), but the current path brings us to that level of warming in just over 30-50 years, not over the 84 years remaining in this century. And just maintaining current rates of warming without significant added feedbacks from the Earth System would result in Earth hitting close to 3 C warming by 2100 — a level that would inflict severe harm to life on Earth, including human civilizations.

september-of-2016

(According to NASA, September 2016 edged out September 2014 as the hottest September in the 136-year climate record. This occurred while the Equatorial Pacific was flipped into a cool phase, which tends to lower global temperatures. Despite this natural variability-related switch pulling global temperatures down, NASA shows a globe in which few regions experienced below-average temperatures and where the highest concentration of record-warm temperatures are centered near the northern polar region. This display of counter-trend warming and strong polar amplification are both signature effects of human-caused climate change. Image source: NASA GISS.)

Focusing back on 2016, it appears the La Nina that struggled throughout August and early September is again making a decent attempt to form, at least as a weak event. This should tend to pull October, November and December temperatures into the 1 to 1.1 C above 1880s departure range. As a result, final averages for 2016 should be slightly lower than averages for the period running from December to September. But, as noted above, we are still on track to see a very significant jump above the 2015 end atmospheric temperature totals.

Climate Impacts from Added Global Heat Continue to Worsen

All this extra heat in the system will work to worsen the already extreme climate and weather events we are seeing. Potentials for droughts, floods, heatwaves and wildfires will increase. High atmospheric moisture loading will continue to pump up peak storm potentials when storms do form. Added heat will tend to accumulate at the poles more than in the tropics or middle latitudes. As a result, upper-level wind patterns will likely continue to see more anomalous features along a worsening trend line. Ice in all forms will see stronger heat forcings overall, adding risk that both land and sea ice melt rates will increase.

impacts-to-the-cryosphere

(In the mid-2010s, Earth entered a temperature range averaging 1 C above pre-industrial levels. Such temperatures begin to threaten key climate impacts like permafrost thaw, 3-4 meters of sea-level rise from West Antarctic Ice Sheet melt, risk of up to 80 percent mountain glacier loss, complete Arctic sea ice loss during summer, and 6-7 meters of sea level rise from Greenland melt. In the near 1 C range, risks of these impacts, though a possibility, remain somewhat lower. But as temperatures approach 1.5 and 2 C above pre-industrial levels, risks rise even as West Antarctic glacial melt and polar ocean acidification start to become serious factors. Image source: Solving the Climate Stalemate.)

At 1 to 1.3 C above 1880s levels, we should see a quickening in the rate of sea-level rise. How much is uncertain. However, this temperature range is very close to peak Eemian Stage levels when oceans were around 15 to 25 feet higher than they are today. The current rapid rate of temperature change will also continue to have worsening impacts on creatures who are adapted to inhabit specific climate zones. The rapid rise in global temperatures is forcing an equally rapid movement of climate zones toward the poles and up mountains. This affects pretty much all life on Earth and unfortunately some species will be hard-pressed to handle the insult as certain habitats basically move off-planet. This impact is particularly true for corals, trees and other species that are unable to match the rapid pace of climate zone motion. We have already seen very severe impacts in the form of mass coral and tree death the world over. Warming in the 1 to 1.3 C range also provides an increasing ocean stratification pressure — one that has already been observed to increase the prevalence of ocean dead zones and one that will tend to shrink overall ocean vitality and productivity.

Fierce Urgency For Climate Action

Despite all these negative impacts, we are still currently outside the boundary of the worst potential results of climate change. Stresses are on the rise from various related factors, but these stresses have probably not yet reached a point of no return for human civilization and many of the reefs, forests, and living creatures we have grown to cherish. Rapid mitigation through a swift transition away from fossil fuels is still possible. Such a response now has a high likelihood of successfully protecting numerous civilizations while saving plant and animal species across the planet. That said, at this point, some damage is, sadly, unavoidable. But the simple fact that we are now starting to face the harmful consequences of a century and a half of fossil fuel burning is no excuse for inaction. To the contrary, the beginning of these harms should serve as a clarion call for our redoubled efforts.

Links:

NASA GISS

NOAA ESRL

NOAA El Nino

Climate of Gavin

The Truth About Climate Change

COP 21: Why 2 C?

Solving the Climate Stalemate

Hat tip to Kevin Jones

Hat tip to Florifulgurator

Coastal Cities, Critical Infrastructure Unprepared to Face the Rising Tides of Climate Change

Civitasthe latin word for city and the root word for civilization. Civilization, in other words, is a collection of component cities. And, by extension, any major threat to a large number of cities is a threat to civilization itself. Such is the case with human-forced climate change.

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It’s a sad fact that many of the hundreds of coastal cities around the world are living on borrowed time. Current greenhouse gas levels — topping out near 408 parts per million CO2 (and 490 parts per million CO2e) this year — will need to fall in order to prevent 1-3 C of additional warming and 25 to 60 feet or more of sea level rise over the coming decades and centuries. And even if we somehow dialed atmospheric CO2 and CO2e levels back to 350 ppm, it’s likely that we’d still see seas eventually rise by 10-20 feet over the long term due to already destabilized glaciers in places like Greenland or West Antarctica.

But with fossil fuel burning continuing at near record levels globally, and with many corporations and political bodies around the world dragging feet on greenhouse gas emissions cuts, the level of heat-trapping carbon held aloft in our airs will continue to rise for some time. These vastly irresponsible actions will further heat the atmosphere and ocean — melting a greater share of the world’s land ice and forcing seas to ultimately rise even more. If CO2e exceeds a range of 550 to 650 parts per million — which could easily happen even under so-called moderate rates of fossil fuel burning before the middle of the 21st Century — then all the land ice on Earth will be placed under melt pressure. And that vast sum of ice melt represents about 220 feet of sea level rise long term so long as the greenhouse gas melt and heat pressure remains.

Sea level rise AVISO July 2016

(Seas have been rising in concert with ocean warming and fossil fuel burning since the start of the 20th Century. At first, during the first half of the 20th Century, rates of rise were less than 1 mm per year. By the 1993 through 2016 period, sea level rise averaged 3.39 mm per year. And since 2011, the rate of rise appears to have steepened into the range of 4 to 6 milimeters per year. Image source: AVISO.)

Even more disturbing is the fact that in the geological past, glacial melt has not tended to process in a gradual, orderly fashion. Instead, initial gradual melt has, in deep history, often been punctuated by very large melt pulses as glacial systems rapidly succumbed to warming environments. And with human warming now proceeding at a pace about 20 times faster than the end of the last ice age, the risk for rapid melt has been greatly enhanced.

Despite continued snide claims by climate change deniers to the contrary — it really is a global emergency. One that includes difficult impacts now and a rising risk of far worse impacts to come. A very real kind of long emergency for human civilization and the natural world combined. One made no less worse by its current deceptively slow, if massive and inexorable, advance.

Hundreds of Cities Under Threat

Due to this threat posed by human-forced warming of the global climate system, cities that have lasted for hundreds or thousands of years now face a serious risk that they will ultimately be devoured by rising tides. Around the world, nearly half of the world’s approximate 4,000 cities with populations of greater than 100,000 people sit on or near the coastline, at elevations below 220 feet, or near bodies of water that are vulnerable to sea level rise. Under the continued pressure of human-forced warming on global ocean levels, a good number (5-10 percent) of these cities may begin to succumb to rising tides in as little as a 10-30 years. And, long term, over 30-300 year time frames, pretty much all are threatened if the world continues burning fossil fuels.

Greenland Glacial Melt

(Glacial melt, like from this pond-riddled and melt-darkened section of Greenland as seen on July 8 of 2016, threatens many coastal cities this Century. With human warming of the Earth atmosphere approaching 2 C, the threat of large glacial outburst flood events that rapidly push sea levels higher is rising. But even gradual sea level rise is already disrupting cities and the infrastructure that supports them. Image source: LANCE MODIS.)

New Orleans, London, Sydney, Shanghai, Los Angeles, New York, Alexandria, Amsterdam, Miami, Norfolk, Washington DC, and Toyko are just a handful of the major cities that are mostly low-lying or that contain large low-lying sections. And all are below the 220 foot sea level rise line that current levels of fossil fuel burning will begin to put into long-term play before mid-Century.

Infrastructure is the First Vulnerability

While complete inundation by rising tides is the ultimate issue, cities do not have to face such drowning to fall under threat. Water supplies, transportation nodes and arteries, food supplies, and energy production and distribution facilities all represent lynch-pins that, if disrupted, can take down a city’s ability to effectively function. And sea level rise often threatens many or all of these critical supports well before the problem of total inundation becomes an issue.

Miami, for example, now faces a combination of these threats due to the presently emerging early outlier effects of human-forced sea level rise. There, just one foot of rising tides since the early 1870s has now put 2.4 million of Miami’s residents and 1.3 million homes within 4 feet of the high tide mark. By 2015, that relatively minor sea level rise had increased tidal flooding by 50 percent. Roadways and neighborhoods were more frequently cut off by the rising waters — which prompted the election of Philip Levine as Mayor of Miami Beach and the implementation of his 400 million dollar project to elevate roads and add pumps.

The city’s water supply, provided by a fresh water aquifer running through porous limestone, is protected from ocean salt water intrusion by a fresh water barrier of canals. A mere six additional inches of sea level rise will render the current system both ineffective and vulnerable to over-topping due to heavy rainfall events.

Power Stations, Roads, and Airports

By 2030, Miami is expected to see between 6-10 more inches of sea level rise. By the end of this Century, it will probably see at least 6 feet — and that’s if we don’t pursue business as usual fossil fuel burning and if the world’s glaciers mostly behave themselves by not giving us a big, angry melt pulse in response to our insults. The result is that not only Miami, but the far-flung critical infrastructure that supports it is also under threat.

In this context, Miami’s airport is just 8 feet above the high tide line. The nearby Turkey Point Nuclear facility which provides energy to the city and a big chunk of South Florida is about 6 feet above the high tide line. And though its reactors are elevated by another 20 feet of concrete buttressing, this Century’s predicted sea level rise would flood its grounds and surrounding roadways — likely rendering it inoperable.

Nuclear Stations Sea Level Rise

(Long term inland extent of sea level rise under 2 C and 4 C warming scenarios for US East and Gulf Coasts puts 13 nuclear facilities in the firing line. And an unexpected melt pulse or powerful storms riding on the top of sea level rise present a risk of flooded reactors. Such an inland rush of waters would also drown scores of coastal US cities, cut off roadways, flood aquifers, inundate crops, submerge airports, and sink conventional power stations. Image source: Nuclear Regulatory Commission, National Geographic, Climate Central.)

In the US, nine nuclear power stations are located on the coast. Another 13 are vulnerable to sea level rise. These sites are located near the ocean or along ocean fed rivers. They are ultimately vulnerable to sea level rise spurred by 2 or 4 degrees Celsius worth of warming. Without a herculean effort to not only reduce greenhouse gasses, but to recapture them from the atmosphere, 2 C warming is already locked in (this Century or longer term). The 4 C number is possible by late this Century under business as usual fossil fuel burning and is possible long term (500 year time scales) under the continuous 490 ppm CO2e forcing now in place.

Many large coal and gas power plants which also require heavy flows of water to support their operations are located near the coast. Oil refineries, which rely on shipping are often very close to sea level. Many major roadways are vulnerable to cut-off from sea level rise. And an amazingly large number of key airports are below a 20 foot elevation.  A small sampling includes San Diego International Airport at 13ft in elevation, Santa Barbara — 10 feet, Vancouver –14 feet, Portland 20 feet, JFK — 13 feet, La Guardia — runway elevations between 7 and 21 feet, Reagan National — 13 feet.

New York Also Armoring Against Rising Tides

In the northeastern US, another city has recently had a harsh global warming wake-up call. About a foot of east coast sea level rise added to the approximate 13 foot storm surge of Hurricane Sandy to flood Staten Island and large sections of lower Manhattan. The local power station flooded — propelling the city into darkness even as the subway system drowned and one neighborhood filled with water and burned at the same time.

Post Sandy responses have resulted in a flurry of activity. Fully 60 billion dollars has been spent to rebuild and a good chunk of that has gone to making the city more protected against both storms and rising sea levels. High rises are now required to lift critical infrastructure such as water pumps and spare generators into the upper stories should lower levels flood. A big flood resiliency effort, starting with the 3 billion dollar construction of a 10 foot high, two mile long flood barrier in 2017, is underway. One that may buttress much of lower Manhattan behind a U shaped wall meant to deflect both rising tides and worsening storms.  And a new park now features hills up to 70 feet above sea level.

Post-Glacial_Sea_Level

(At the end of the last ice age, as global temperatures approached 2 degrees Celsius above previous averages, large melt pulses from Antarctica and Northern Hemisphere Ice Sheets forced seas to rise by as much as 10 feet per Century. Human-forced warming is currently about 20 times faster than warming at the end of the last ice age. Current rates of warming and greenhouse gas emissions threaten to generate a 2 C warming by or even before the middle of this Century. Large melt pulses forced by such conditions would put cities like New York under risk of rapid inundation. Image source: Post-Glacial Sea Level Rise.)

These efforts appear to be aimed at facing off against another 1 foot of sea level rise for Manhattan by 2030 and a North Atlantic Ocean that is increasingly riled by powerful storms due to warming related climate instabilities. New York is digging in for the fight of its life. And for good reason. 10 percent of US gross domestic product funnels through this city of 8.5 million and over 100 billion dollars worth of real estate now sits in a high risk flood zone.

But build and buttress as it might, New York is hopeless in the long term if we can’t somehow stop human carbon emissions soon. If we can’t somehow start to draw carbon out of the air. If we can’t do these things, then New York, Miami and thousands of other coastal cities will ultimately face 25 feet of sea level rise or much, much worse. And the far flung infrastructures that they rely on will all, increasingly, need more and more costly and involved protections before they too succumb to the rising tides.

Links/Attribution/Statements:

Rising Seas Threat to Miami

Miami Nuisance Flooding Up by 50 Percent

As Waters Rise, Miami Beach Builds Higher Streets

Miami Herald — Sea Level Rise

Nuclear Regulatory Commission

Sea Level Rise — Are Coastal Nuke Plants Ready?

Sea Level Rise Risk to Coastal Nuclear Plants

Can New York Be Saved in the Era of Global Warming?

Post-Glacial Sea Level Rise

New Park Built to Withstand Epic Storms

Global Cities Map

Ancient Civilization

Scientific hat tip to Dr. James Hansen

Scientific hat tip to Dr. Eric Rignot

Scientific hat tip to Dr. Jason Box

Hat tip to DT Lange

Hat tip to Scott

Hat tip to Genomik

Hat tip to Cate

Tottering Totten and the Coming Multi-Meter Sea Level Rise

A new scientific study has found that the Totten Glacier is fundamentally unstable and could significantly contribute to a possible multi-meter sea level rise this Century under mid-range and worst case warming scenarios.

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408 Parts per million CO2. 490 parts per million CO2e. This is the amount of heat-trapping CO2 and total CO2 equivalent for all heat-trapping gasses now in the Earth’s atmosphere. Two measures representing numerous grave potential consequences.

We’re Locking in 120-190 Feet of Sea Level Rise Long Term

Looking at the first number — 408 parts per million CO2 — we find that the last time global levels of this potent heat-trapping gas were so high was during the Middle Miocene Climate Optimum of 15-17 million years ago. During this time, the Greenland Ice Sheet did not exist. East Antarctic glacial ice was similarly scarce. And the towering glaciers of West Antarctica were greatly reduced. Overall, global sea levels were 120 to 190 feet higher than they are today. Meanwhile, atmospheric temperatures were between 3 and 5 degrees Celsius hotter than those experienced during the late 19th Century.

Antarctica Below Sea Level

(Large sections of Antarctica rest below sea level. A physical feature that renders substantial portions of Antarctica’s glaciers very vulnerable to rising ocean temperatures. Since the latent heat content of water is substantially higher than that of air, even comparatively small ocean temperature increases can cause significant melt in sea-facing glaciers and in below sea level glacial basins. Image source: Potential Antarctic Ice Sheet Retreat Driven by Hydrofracturing and Ice Cliff Failure.)

Hitting the 408 ppm CO2 threshold this year catapults the current push for global climate transitions outside of the Pliocene context of 3 to 5 million years ago (topping out at 405 parts per million CO2) and places it in the bottom to mid-range of the Middle Miocene context (300 to 500 parts per million CO2). The 490 ppm CO2e number — due to added atmospheric heating contributions from human-emitted gasses like methane, chlorofluorocarbons, NOx compounds, and others — is enough to catapult our current climate context into the upper Middle Miocene range.

If global greenhouse gasses were to stabilize in this range long-term (for a period of hundreds of years), we would expect the Earth’s climate and ocean states to become more and more like those experienced 15-17 million years ago. Unfortunately, atmospheric concentrations of heat trapping gasses are still rapidly rising due to an increasingly dangerous emission coming from global fossil fuel burning. In addition, risks are rising that the Earth System will begin to contribute its own substantial amounts of carbon — possibly enough to raise the CO2e number by around 50 to 150 ppm over the next few centuries. Two contributions — one we control and another we do not — that risk swiftly pushing the global climate context into a 550 to 650 ppm CO2e range that is enough to eventually melt all the glacial ice on the planet.

Glacial Inertia vs Lightning Rates of Warming

It’s a tough climate state. A context that many scientists are still having difficulty coming to grips with. First, the global glacier research community is still looking at the world’s potential future ice melt in Pliocene and Eemian contexts. This makes some sense given the fact that current atmospheric warming in the range of 0.9 to 1.3 C above 1880s values is more in line with those two climate epochs (the Eemian saw seas 10-20 feet higher than today and the Pliocene saw seas at 25-75 feet higher). But it doesn’t take into account the underlying heat forcing and the likely climate end-state.

Second, we don’t really have a good grasp on how fast or slow glaciers will respond to the added heat we’re putting into the Earth System. We do know that at the end of the last ice age, melting glaciers contributed as much as 10 feet of sea level rise per Century. But this was during a time of comparatively slow global temperature increase at the rate of about 0.05 C per Century — not the current rate in the range of 1.5 to 2 C per Century, which is 30 to 40 times faster.

10 Feet of Sea Level Rise South Florida

(What 10 feet of sea level rise would do to South Florida. Given the increasing vulnerability of glaciers around the world to human-forced warming, there’s a rising risk that seas could rise by 10 feet before the end of this Century. Image source: Climate Central.)

In early studies, much weight has been given to glacial inertia. And older climate models did not include dynamic ice sheet vulnerabilities — like high latent-heat ocean water coming into contact with the submerged faces of sea-fronting glaciers, the ability of surface melt water to break up glaciers by pooling into cracks and forcing them apart (hydrofracturing), or the innate rigidity and frailty of steep ice cliffs which render them susceptible to rapid toppling. But now, new studies are starting to take these physical melt-amplifying processes into account and the emerging picture is one in which glacial melt and sea level rise may end up coming on at rates far more rapid than previously feared.

Overall, when taking a look at these newly realized ice-sheet weaknesses, it’s worth noting that the total heat forcing impacting the world’s ocean, air, and glacial systems is now rising into a range that is much more in line with Middle Miocene values. And that global temperatures are now increasing at a lightning rate that appears to be unprecedented in at least the past 60 million years.

Tottering Totten

It’s in this dynamic, rapidly changing, and arguably quite dangerous climate context that new revelations about the stability of one of East Antarctica’s largest glaciers have begun to emerge. In size, the Totten Glacier is immense — covering an area the size of California in mountains of ice stretching as high as two and a half miles. If all of Totten were to melt, it would be enough to raise seas by around 11 to 13 feet — or about as much as if half of the entire Greenland Ice Sheet went down.

Edge of the Totten Glacier

(The Totten Glacier, at lower edge of frame, faces a warming Southern Ocean. How rapidly this great mass of ice melts will, along with the destabilization of numerous other glaciers around the world due to a human-forced warming, determine the fates of numerous coastal cities and island nations during this Century and on into the future. Image source: LANCE-MODIS.)

Last year, a study found that warm, deep circumpolar water was beginning to approach ice faces of the Totten Glacier plunging 1 mile below the surface of the Southern Ocean. The study observed a rapid thinning that appeared to have been driven by this new influx of warmer ocean water near the glacier base:

Totten Glacier… has the largest thinning rate in East Antarctica. Thinning may be driven by enhanced basal meltingWarm modified Circumpolar Deep Water, which has been linked to glacier retreat in West Antarctica, has been observed in summer and winter on the nearby continental shelf beneath 400 to 500 m of cool Antarctic Surface Water…We identify entrances to the ice-shelf cavity below depths of 400 to 500 m that could allow intrusions of warm water if the vertical structure of inflow is similar to nearby observations. Radar sounding reveals a previously unknown inland trough that connects the main ice-shelf cavity to the ocean. If thinning trends continue, a larger water body over the trough could potentially allow more warm water into the cavity, which may, eventually, lead to destabilization of the low-lying region between Totten Glacier and the similarly deep glacier flowing into the Reynolds Trough (emphasis added).

Observed increasing melt rates for such a huge slab of ice in Eastern Antarctica was generally seen as a pretty big deal among glacial scientists and a flurry of additional research soon followed. By last week, a model study had found that Totten alone could produce nearly a meter of sea level rise before the end of this Century if global warming forces ocean waters to heat up by 2 C or more near the Totten Glacier. The study also found that 5 C worth of local ocean warming would be enough to force nearly 3 meters worth of sea level rise from this single large glacier over a relatively short time-frame.

Donald D. Blankenship, lead principal investigator for the new ICECAP study noted:

“Totten Glacier’s catchment is covered by nearly 2½ miles of ice, filling a California-sized sub-ice basin that reaches depths of over one mile below sea level. This study shows that this system could have a large impact on sea level in a short period of time.”

Like many large glaciers around the world, a huge portion of Totten’s ice sits below sea level. This feature makes the glacier very vulnerable to ocean warming. Water carries far more latent heat than air and just a slight rise in local ocean water temperature can contribute to rapid ice loss. Totten itself rests in three large below sea level basins. And study authors found that 2 C to 5 C warming of local ocean waters with somewhat greater local air temperature increases was capable of flooding these basins in stages — forcing Totten’s glacial ice to flow out into the Southern Ocean and provide significant contributions to sea level rise.

Unfortunately, Totten is just one of many large glacial systems that are now destabilizing across Antarctica. And researchers are now beginning to identify significant potential sea level rise contributions from Antarctica alone (ranging from two feet to nearly two meters) before the end of this Century. In New Scientist, during March, Antarctic researcher Rob Deconto notes:

“Today we’re measuring global sea level rise in millimetres per year. We’re talking about the potential for centimetres per year just from [ice loss in] Antarctica.”

Centimeters per year sea level rise is about ten times faster than current rates and implies 100 year increases — once it gets going — in the range of 2 to 3 meters. Such increased melt does not include Greenland’s own potential sea level rise contribution. Nor does it include sea level rise from other glacial melt and ocean thermal expansion. As such, it appears that multi-meter sea level rise is becoming a more and more distinct possibility this Century. Furthermore, the paleoclimate context is now pointing toward catastrophic levels of overall melt and sea level rise if global greenhouse gasses aren’t somehow stabilized and then swiftly reduced.

Links:

Repeated Large-Scale Retreat and Advance of Totten Glacier Indicated by Inland Bed Erosion

The Totten Glacier

The Human-Warmed Southern Ocean Threatens Major Melt for East Antarctica

Fundamentally Unstable — Scientists Confirm Their Fears About East Antarctica’s Biggest Glacier

Potential Antarctic Ice Sheet Retreat Driven by Hydrofracturing and Ice Cliff Failure

Unstable East Antarctic Glacier Has Contributed to Sea Level Rise in the Past

Sea Levels Set to Rise Far More Rapidly Than Expected

Unexpected Antarctic Melt Could Trigger 2 Meter Sea Level Rise

Entering the Middle Miocene

The Middle Miocene

LANCE MODIS

Northeast Greenland Begins Ominous Collapse — Giant Zachariae Isstrom Most Recent to Destabilize

November 12, 2015:

North, south, east, and west. At all points of the compass, the entire outer edge of the Greenland Ice Sheet is flooding into the oceans with increasing velocity. For NASA it’s the absolute worst kind of OMG realization. For the world’s warming oceans and airs are clearly worsening an already visible Greenland melt. And a new report just out of the University of California (Irvine) today shows that a massive glacier containing enough water to raise seas by more than 1.6 feet (0.5 meters) is the most recent of a growing number of these ice giants to initiate a swift rush into the ocean.

Called Zachariæ Isstrøm, this enormous glacier dominates a large section of the northeast-facing shores of Greenland. The glacier, hundreds of feet tall and plunging hundreds more feet below the ocean surface, like many in our world, now faces the combined threat of warming airs and waters. A double insult that, according to researchers, over the past 15 years has led to first destabilization and then a rapid seaward acceleration.

Zachariae Isstrom Surges Toward Ocean

(1975 to 2015 time lapse shows recent rapid retreat of the Zachariæ Isstrøm glacier’s front. The dark green line marks the 2003 extent of the glacial front. Note the rapid retreat through 2015 in lighter shades blending toward white. Image source: Jeremie Mouginot/UCI via Climate Central.)

According to the new study — Fast retreat of Zachariæ Isstrøm, northeast Greenland — published today in Science, the glacier’s rate of seaward movement has tripled in velocity even as the pace of ice thinning along its grounding line doubled:

Warmer air and ocean temperatures have caused the glacier to detach from a stabilizing sill and retreat rapidly along a downward-sloping, marine-based bed… After 8 years of decay of its ice shelf, Zachariæ Isstrøm, a major glacier of northeast Greenland that holds a 0.5-meter sea-level rise equivalent, entered a phase of accelerated retreat in fall 2012. The acceleration rate of its ice velocity tripled, melting of its residual ice shelf and thinning of its grounded portion doubled, and calving is now occurring at its grounding line.

In total, more than 4.5 billion tons of ice is now estimated to be flooding out from this glacier and into the ocean each year. That’s a mountain of ice about 4.5 cubic kilometers in size hitting the world’s waters from just this single glacier every time the Earth completes one circuit around the sun. In other words, Greenland just opened a new floodgate to the North Atlantic. Researchers publishing the study estimate that it will take between 20 and 30 years for the glacier to melt back to an underwater ridge line that should somewhat slow its melt. But the real news here is that a human-forced warming of the globe has set a monstrous pile of ice, once thought stable, into a motion that will result in yet more global sea level rise.

To the north of Zachariæ Isstrøm sits the also melting Nioghalvfjerdsfjorden. A giant of ice in equal volume to that of Zachariæ. Nioghalvfjerdsfjorden sits on an upward sloping bed and so is not as subject to rapid destabilization as Zachariæ. However, the study found that the combined total ice mass of both glaciers in the range of 1 meter worth of sea level rise was now involved in a significant melt that would “increase sea-level rise from the Greenland Ice Sheet for decades to come.”

greenland-topography

(Map of Greenland topography showing large sections of the interior resting near or below sea level. As a result, warming waters have numerous avenues for invasion into the Greenland Ice Sheet. Numerous ways to melt Greenland ice from below. Zachariæ Isstrøm covers the upper right hand section of this image — sitting astride a low elevation channel the plunges deep into the heart of the current ice mass. Image source: Livescience.)

Greenland is the last major remaining bastion of glacial ice in the Northern Hemisphere. Surrounded on all sides by warming airs and waters, it is the most vulnerable large ice mass to the forces set in play by a human warming of the global environment. In total, Greenland holds enough ice to raise seas by 23 feet. And, in the geological past, just 1.5 to 2.5 degrees Celsius worth of temperature increase above Holocene averages was enough to melt much or all of it.

Currently, human warming by Greenhouse gasses has pushed global average surface temperatures into a range about 1 degree Celsius hotter than the 1880s. It’s a temperature running into ranges that are now comparable with the Eemian — the interglacial period that occurred between 115,000 to 130,000 years ago. A period when oceans were about 13 to 20 feet higher than they are today.

But perhaps even more concerning is the fact that global greenhouse gas concentrations in the range of 400 ppm CO2 and 485 ppm CO2e are enough now to warm the Earth by 2 to 4 degrees Celsius long-term. It’s a heat forcing that would likely spell the end for Greenland’s ice if it remained in place for any significant period. A heat forcing more comparable with Pliocene and Miocene ranges when the world’s glaciers were even more greatly reduced and seas were 30 to 130+ feet higher than they are presently.

Unfortunately, what the building global heat and currently very high greenhouse gas heat forcing means is that the Earth System will continue to accumulate warmth for some time. And as this happens more and more glaciers — both in Greenland and Antarctica — are going to destabilize, speed up, and contribute increasing melt volumes to the world ocean. Eliminating greenhouse gas emissions at this time and pushing to return to atmospheric levels in ranges below 350 ppm CO2 is therefore absolutely necessary if we are to have much hope of preventing ever-worsening rates of glacier destabilization and related contributions to sea level rise.

Links:

Collapsing Greenland Glacier Could Raise Seas by Half a Meter

Fast retreat of Zachariæ Isstrøm, northeast Greenland

Once Stable Glacier Facing Melt

NASA Science Missions — Oceans Melting Greenland (OMG)

Greenland Just Opened a Major New Floodgate to the Ocean

Livescience

Pliocene Climate

Miocene Climate

Departures in Pliocene Sea Level Record

Greenland Weather Underground

Hat tip to Todaysguestis

Hat tip to Colorado Bob

Hat tip to Ryan in New England

The Frankentides are Coming — US East Coast to See Season of Flooding From El Nino + Sea Level Rise This Winter

According to preliminary reports from NOAA, this Fall, Winter and Spring will likely bring an abnormal number of flooding tides to the US East Coast. These emperor and king tides are primarily driven by sea level rise — a knock on impact of human-forced warming. But during an El Nino year, as with this year, wind patterns along the East Coast tend to drive tides even higher. At El Nino times, lows tend to form off the US East Coast. These lows tend to generate a consistent northeasterly wind that pushes against the northward flow of the Gulf Stream. This action reduces the Gulf Stream’s ability to pull water away from our shores, and some of that water rebounds against the US East Coast.

During a normal year, this would somewhat increase the height of East Coast tides. But, due to Greenland melt pumping fresh water into the North Atlantic, the heat and salt driven circulation that generates the Gulf Stream is weakening (See Signs of Gulf Stream Weakening). So this year’s series of El Nino lows are forming over seas that are already rebounding against the US East Coast. Forming in seas that have already risen due to the melting of glaciers around the world. A NOAA press release from September notes that recent findings:

“…build upon two nuisance flooding reports issued last year led by NOAA scientists William Sweet and John Marra. The previously published reports show coastal communities in the United States have experienced a rapid growth in the frequency of nuisance tidal flooding, a 300 to 925 percent increase since the 1960s, and will likely cross inundation tipping points in the coming decades as tides become higher with sea level rise”

“We know that nuisance flooding is happening more often because of rising sea levels, but it is important to recognize that weather and ocean patterns brought on by El Niño can compound this trend,” said Sweet.”

image

(The 2015 El Nino — the year sea level rise came home to roost for the US East Coast. NOAA predicts a significant increase in the number of tidal flooding events all up and down the East Coast due to a combination of El Nino and impacts related to human-forced climate change. Image source: NOAA.)

It is due to this confluence of factors that we are likely to see some pretty extreme flooding tides anywhere from Miami to Maine. Flooding tides that, according to NOAA, are 33 to 125 percent more frequent than even the recently elevated trend. Tides that, as we have already seen (see below) are much higher than during any typical year — El Nino or no. Such impacts are likely to occur even without the influence of strong Nor’easters. But for the East Coast, Nor’easters and El Nino tend to go hand in hand.

So it’s shaping up to be a flooding season. One that wouldn’t have happened before. One brought on by the impacts of a human-forced warming. And one that is but a harbinger of more flooding to come.

Fall of 2015 Already Seeing Substantial Inundation Events

Over the past few weeks, a freak series of high tides inundated large sections of the U.S. East Coast. In Charleston, South Carolina, on October 27, a high tide peaked at 8.67 feet above mean low water. That’s the highest tide for Charleston since Hurricane Hugo roared ashore in 1989. But in this case, there was no category 4 hurricane. Just a ridiculous amount of water flooding in from the ocean. In Savannah, Georgia tides ran 10.43 feet above mean low water on the same day. Again, no storm, just a rising ocean flooding out roadways and inundating homes and neighborhoods. Only a couple of days later, on October 29th, large sections of Boston Harbor flooded under perfectly blue skies.

Tybee Flood

(Flooding, primarily due to sea level rise and an extreme high tide, inundates coastal lands near Tybee, Georgia on October 27th. It was the worst flooding since a category 2 hurricane hit the region in 1935. This year, there was no hurricane. Just sea level rise caused by human forced warming combined with the typical impacts of El Nino on East Coast tides. Image source: Blame Sea Level Rise.)

For stormless days, this level of tidal flooding is unprecedented. It’s a validation, just one month later, of NOAA predictions. If anything, these tides were even higher than expected. Tides influenced by sea level rise, glacial melt in Greenland, and by an El Nino driven shift in wind patterns. Had these tides coincided with a strong Nor’easter or a Hurricane, what we’d be looking at is a level of flooding that would almost certainly have exceeded the worst such events ever to strike the US East Coast. In effect, what we see is that sea level rise due to human forced warming of the globe is starting to have a greater and greater impact on these shores. An awful and early impact that will only worsen as time and human warming progress.

A Global Problem Set Off By Human Warming

Over the longer term, there are a lot of people in the path of this global trend of rising waters. In the US alone, more than 143 million people live in coastal communities. And the seas, due to human-forced warming are on the rise.

But its not just the US East Coast that’s in trouble. Practically everywhere, seas are rising. Global temperature increases of about 1 degrees Celsius above 1880s values are causing the oceans to thermally expand. In addition, glacial melt from mountain systems, Greenland and Antarctica is contributing ever-increasing volumes of water to the global ocean, forcing on the waters’ rise at ever-increasing rates. Currently, long term trends indicate a 3.3 millimeter per year average increase in the height of the world’s oceans (from 1993 to present). And as the world starts to close in on 2 degrees Celsius above 1880s averages, the pace of that rise is expected to ramp up and up.

Already, current sea level rise presents increasing problems to coastal regions across the globe. Much of the impacts we presently see are due to salt water invasion of low lying regions, nuisance flooding events, the amplification of storm driven tides, and increasing instances of what are now called king and emperor tides. Adding complexity to this global warming related problem is the fact that seas do not rise in a uniform manner. This lack of global uniformity of sea level rise results from gravity’s affects on the displacement of waters and from the influence of water outflows from glaciers on ocean currents. As a result, global sea level rise can generate hot spots where rates of rise are significantly in excess of the global average.

US East Coast as Sea Level Rise Hot Spot

Global Sea Surface Height Anomaly NOAA

(Over the past few months, a bulge of water more than 1.3 feet higher than the 1981 to 2013 global average has expanded off the US East Coast. This bulge is driven by a combination of Gulf Stream slowdown due to Greenland melt, overall sea level rise due to global warming, and due to an El Nino pattern that drives northeasterly winds off the US East Coast. This year, this extreme bulge is expected to bring on a significant increase in the number of flooding tides. Tides that could be compounded by the effects of strong nor’easters that tend to be generated during El Nino years. Image source: NOAA CPC.)

Unfortunately, as we have seen above, the impacts of gravity rebound and current changes related to glacial melt put the East Coast of the United States directly in the path of a significant rise in ocean water. Specifically, Greenland melt results in a slowing down of the Gulf Stream. And it is the northward draw of the Gulf Stream that pulls about 3 feet worth of sea level rise away from the US East Coast. Slow down the Gulf Stream by dumping cold water into the North Atlantic and you can get about a foot of sea level increase off the US East Coast. Stop it completely and all that 3 feet of water comes sloshing back. Add any global sea level rise due to ocean warming and glacial melt on top of that and you can see why the US East Coast can quickly get into trouble.

All in all, scientists expect sea level rise for the US East Coast to be nearly double the global average predicted for this Century. And what this means is that more and more coastal flooding is on the way.

Links:

The State Did Warn Us

Can’t Get Home? Blame Sea Level Rise

NOAA: El Nino May Accelerate Nuisance Flooding

Melting Ice in West Antarctica Could Raise Seas by 3 Meters

Historic Tides From Sea Level Rise and Supermoon Flood US East Coast

NOAA CPC

Hat Tip to Greg

Hat Tip to Colorado Bob

Hat Tip to DT Lange

We’re Gonna Need a Bigger Graph — Global Sea Level Rise Just Went off the Chart

From end 2014 through Fall of 2015 global sea levels surged. Building heat hitting +1 C above 1880s averages in the atmosphere-ocean system continued to set off a range of what appear to be ramping impacts. Thermal expansion grew more dramatic as oceans continued to heat up during what may be a record El Nino year. Rates of land ice melt continued to increase — providing a greater and greater fraction of overall global sea level rise. And global ocean currents showed signs of a melt-spurred change — which resulted in an uneven distribution of this overall rise.

We’re Going to Need A Bigger Graph

During that less than one year time, seas rose by fully 1 centimeter. That’s three times the ‘normal’ rate that’s been roughly ongoing since the early 1990s. A big bump that’s now part of a three-and-a-half-year, 3-centimeter surge. One more sign that global sea level rise is starting to really ramp up.

AVISO Sea level rise

(Global sea level rise since 1992 hits past the 8 centimeter mark in the AVISO altimetric graph. Image source: AVISO.)

This big, one-centimeter, jump topped the previous AVISO graph, which went up to 8 centimeters, forcing the measure to generate a new graph with a 9 centimeter top like. In other words, ‘we’re gonna need a bigger graph’ (See the old, smaller, graph here). Unfortunately, with some of the world’s top scientists predicting the potential for an exponentially increasing rate of sea level rise through this Century, it appears that ‘we’re gonna need a bigger graph’ may well become the scientific rallying cry of the age.

Possibility of Exponential Increase in Rate of Sea Level Rise

This year’s seemingly-staggering, 1 centimeter and counting, jump in sea level in less than one year, if maintained over the course of a century would result in a more than 1 meter global rise. Sadly, many new studies on the rate of glacier destabilization in Antarctica and Greenland hint that such a significant jump in sea level is not only likely, but may even be significantly exceeded under business as usual or even a moderately curtailed rate of fossil fuel burning.

A new study led by former NASA GISS head Dr. James Hansen points to the possibility of as much as 3 meters of sea level rise by mid Century and 7 meters or more of sea level rise by end Century even if the global economy somewhat steps off its current high trajectory of fossil fuel burning.

hansen-sea-level-rise

(Steadily ramping sea level rise that may be the start of an exponential curve. Image source: Research Conducted by Dr. James Hansen.)

Such massive rates of sea level rise would clearly be catastrophic.

In such cases, we’d start to see these kinds of exponential increases really begin to ramp up over the next 10, 20, and 30 years. And, given the rather large bumps we’re seeing in the AVISO measure for the past 3 and a half years, it’s possible we’re at the start of one of these potential step changes.

Links:

AVISO Sea Level Rise

Halfway to 2 C — World Approaching Dangerous Climate Milestone

Global Sea Level Rise Going Exponential?

Human-Warmed Southern Ocean Takes Aim at East Antarctica

Warning From Scientists: Age of Superstorms, Rapid Sea Level Rise Likely on the Way

Dr. James Hansen Columbia University

 

 

Tumbling Down the Rabbit Hole Toward a Second Great Dying? World Ocean Shows Signs of Coming Extinction.

The last time Earth experienced a Great Dying was during a dangerous transition from glaciation and to hothouse. We’re doing the same thing by burning fossil fuels today. And if we are sensitive to the lessons of our geological past, we’ll put a stop to it soon. Or else doesn’t even begin to characterize this necessary, moral choice.

*    *    *    *    *

The Great Dying of 252 million years ago began, as it does today, with a great burning and release of ancient carbon. The Siberian flood basalts erupted. Spilling lava over ancient coal beds, they dumped carbon into the air at a rate of around 1-2 billion tons per year. Greenhouse gasses built in the atmosphere and the world warmed. Glacier melt and episodes of increasingly violent rainfall over the single land mass — Pangaea — generated an ocean in which large volumes of fresh water pooled at the top. Because fresh water is less dense than salt water, it floats at the surface — creating a layer that is resistant to mixing with water at other levels.

Algae Blooms and Red Tides in the Stratified Ocean

This stratified ocean state began to cut the life-giving thread of the world’s great waters. Reduced mixing meant the great ocean currents slowed. Oxygen transport into the depths declined. Moreover, a constant rain of debris in the form of particulate matter from burning forests and nitrogen oxides from the smoldering coal beds fertilized the ocean surface. Food for algae also came from increasing continental run-off. And a spike in iron loading due to glacial melt added yet more fertilizer. Great microbial blooms covered the world ocean, painting its face neon green, blue, or blood red.

antarctic-algae-bloom-terra

(Stratified Ocean waters hosting massive algae blooms. It’s a combination that can quickly rob ocean waters of oxygen. During the Permian, a transition to stratified and then Canfield Ocean conditions led to the worst mass extinction event in the history of life on Earth. Today, the Southern Ocean’s waters are increasingly stratified due to glacial melt run-off of fresh water. In addition, these waters also host very large algae blooms like the ones seen above in a NASA satellite shot from 2012. Image source: NASA and Live Science.)

Rising CO2 levels increased ocean acidification even as the blooms spread toxins through the waters. When the blooms finally exhausted all the available food in their given region, they died off en masse. And by decay they further robbed the waters of life-giving oxygen. At this point the strains to ocean life became extreme and the first mass deaths began to occur. The stress opened pathways for disease. And the warming, de-oxygenating waters forced migrations to different Latitudinal zones and ocean depths. What life there was that couldn’t move, or couldn’t move fast enough died in place.

Transitioning to a Canfield Ocean

At first, ocean deaths appeared prominently in the bottom regions that saw the most rapid declines in oxygen levels and the swiftest increases in temperatures. For not only did the fresh water at the surface of the world’s oceans prevent mixing — it also prevented the oceans from ventilating heat into the air. Instead, the ocean heat was increasingly trapped at depth. Aiding this process of heat transport into the world’s deeps was a bottom water formation that issued from the hot Equator. There, evaporation at the surface increased saltiness. The heavier, hotter, saltier waters sank — carrying with them the Equatorial surface heat which they then delivered to the ocean bottom.

The hot, low oxygen bottom water became increasingly loaded with methane as the heat activated frozen stores. It created an environment where a nasty little set of primordial, hydrogen sulfide producing, creatures could thrive.  These little microbes cannot live in oxygen rich environments. But warm, anoxic bottom waters are more like the ancient environments from which they emerged. Times long past when the world was ruled by microbes in conditions that were simply deadly to the more complex and cold-loving life forms of later times. To most life, the hydrogen sulfide gas produced by these little monsters is a deadly toxin.

Ancient ocean conditions

(Oxygen, iron and hydrogen sulfide content of the world’s oceans over the past 4 billion years. Ancient oceans were hotter than today. They were rich in iron and densely populated with hydrogen sulfide producing bacteria. They were also anoxic. During hothouse events, oceans can again lapse into these ancient ocean states. Called Canfield Ocean environments and named after Dr. Donald Canfield who discovered them, these states are extremely deadly to ocean life. If they become too deeply entrenched, Canfield Oceans can also transform the global atmosphere, resulting in extinctions of land animals as well. Such an event was thought to be the primary killing mechanism during the Permian Extinction. Image source: Nature.)

The rotten-eggs stinking, hydrogen sulfide filled waters at first did their dirty work in silence at the bottom of the warming world ocean. But, steadily, anoxia progressed upward, providing pathways for the hydrogen sulfide producing bacteria to fill up the oceans. Death expanded from the bottom toward the surface.

In all the great mass extinction events but, possibly, one, this heat-driven filling up of the world ocean with deadly hydrogen sulfide gas during hothouse periods represents the major killing mechanism. The other impacts of hothouse waters — ocean acidification and habitat displacement — do provide killing stresses. But the combined zero oxygen environment filled with a deadly gas generates zones of near absolute death in which few things but microbes and jellyfish can live. In rock strata, the anoxic, zones are marked by regions of black as the hydrogen sulfide producing bacteria-filled waters eventually take on the color of tar. In the lesser extinctions, these black zones are confined to the lower ocean levels. In the greater ones, they rise higher and higher.

During the Great Dying, the oceans brimmed full of the stuff. Black, purple and neon green waters bubbled to the surface to belch their lethal loads of hydrogen sulfide gas into the airs. The gas was deadly toxic to land plants and animals alike. And it eventually wafted into the skies, turning it from blue to green and eating away at the protective ozone layer.

In this terrible way, more than 99 percent of all living things were killed off. Of species, about 95 percent of ocean forms were lost with around 80 percent of the land forms being wiped out.

Early Signs of a New Ocean Extinction

The Great Dying of the Permian Extinction 200 million years ago should be a warning to anyone still enamored with the notion that today’s terrifying fossil fuel burning results in any future that is not horrible, wretched, bleak. Today, we dump 11 billion tons of carbon into the air each year — at least six times faster than during the Great Dying. Today, the great melting glaciers are beginning the painful process of ocean death by spreading out their films of stratifying, iron-loaded fresh water. Today fossil fuel industry, industrial farming and warming all together are fertilizing the ocean surface with nitrous oxides, particulates, phosphates flushed down rivers, and an overall increased runoff due to a multiplication of extreme rainfall events.

(The hot blob in the Pacific Ocean is setting off the largest red tide on record. Just one of many dangerous impacts to sea life due to this large region of abnormally warm water.)

And the impacts are visible to anyone who cares to look. In the Pacific Ocean, a climate change related blob of hot water is resulting in mass ocean creature die offs. Low oxygen waters beneath the blob are wrecking large zones of ocean productivity and risking the proliferation of deadly hydrogen sulfide producing bacteria. The largest red tide on record has spun off the hot blob. Covering waters 40 miles wide and 600 feet deep, it has left piles and piles of dead shellfish rotting on beaches across the North American West Coast.

Across the Continent, the Chesapeake Bay suffers a proliferation of dead zones and greatly reduced productivity. There’s a rising risk that, during coming years, increased warming will deliver a heavy blow to life in the Bay and turn one of the world’s greatest estuaries into a large hydrogen sulfide production zone similar to the Baltic Sea. In the Gulf of Mexico, a similar dead zone emerges near the outlet of the Mississippi. And out in the Atlantic Ocean, mobile dead zones now swirl providing a roving surface hazard to both the deep open waters and to the coastal regions that now sit in the firing line.

In the Arctic, recently ice-freed waters are now the host of massive blue and green Algae blooms.

Barent Algae Bloom July 2015

(Large blue and green algae bloom covering the southern Barents Sea during late July of 2015. Large algae blooms are now a frequent feature of previously ice covered waters in a warming Arctic. Image source: LANCE-MODIS.)

Ever since the mid 2000s a massive algae bloom like the one pictured above has dominated the Barents Sea during summer time. Often running as deep as 400 feet, this sprawling mat can rapidly deplete northern waters of vitalizing oxygen and result in mass fish kills. Waters around Greenland, in the East Siberian Sea, the Chukchi, and the Beaufort have also hosted large, and potentially ocean-health threatening algae blooms.

And, in the polynyas and open waters off a melting Antarctica, massive algae blooms are also starting to form. Some of the blooms are so dense they emit a nasty rotten-eggs smell — a sign that sulfide producing bacteria may already be active in some of these waters. Fed by iron from melting glaciers, these immense blooms represent rapid explosions of life that can equally rapidly deplete waters of nutrients and then oxygen as they die off.

The blooms and the related expanding, low oxygen dead zones now range the entire world ocean. And where we see the red, the neon green, the cloudy light blue what we see are the signs of another ocean extinction in the making. An extinction that is likely building faster than at any time in the geological past. But we may still be able to avoid another great dying. The amount of carbon we’ve emitted into the world’s airs is immense, but it is still but a fraction of the carbon explosion that resulted in the Permian die-off. It is still a tiny fraction of the carbon that remains in the ground. The carbon that could be burned but shouldn’t. And a rapid cessation of fossil fuel burning now should, hopefully, be enough to prevent another hothouse spurred great dying in the oceans and upon the lands.

As for continued burning of fossil fuels — that results in ever greater risk of unleashing the horrors of the ancient hothouse. A set of now stirring monsters that we should carefully allow to fall back into slumber — leaving them to rest in dreams of the great long ago where they belong.

Links:

A Deadly Climb From Glaciation to Hothouse: Why the Permian-Triassic Extinction is Relevant to Current Warming

Antarctic Glaciers are Loading the Southern Ocean Up With Iron (Not the Good News Some Are Making it Out to Be)

Large Algae Blooms off Antarctica

Under A Green Sky

Awakening the Horrors of the Ancient Hothouse

Canfield Oceans

Nature

K-T Extinction — Impact or Hothouse Caused?

Climate Change Happening Faster Than Scientists Predicted

How Global Warming Sets off Extreme Weather

Hot Pacific Ocean Runs Bloody

Pacific Algae Bloom is The Biggest Red Tide We’ve Ever Seen

Chesapeake Bay Dead Zones

The Atlantic Ocean’s Whirlpool Dead Zones

LANCE-MODIS

Glacial Outburst Flood — Human Hothouse Displaces Hundreds in Tajikistan

If you lived during the 1880s, when the globe was one degree Celsius cooler than it is now, you’d see far less in the way of heatwaves. But an immense vomiting of greenhouse gasses into our atmosphere and oceans by fossil fuel industry since that time has greatly multiplied these periods of extreme temperatures. So much so that you are now four times more likely to experience a heatwave anywhere on the globe at any given time than you were 135 years ago.

Heatwaves, depending on their intensity, can have serious consequences. The most direct impact is due to the excess heat itself. In the more extreme instances, heatwaves during recent years have featured an ominous capacity to hospitalize tens of thousands. These heat stroke victims, in the worst cases, perish. Such was the case for India and Pakistan this year where hundreds tragically lost their lives due to the impact of increased heat alone.

But if heatwaves occur in regions where glaciers still exist, the impact can be even more profound.

Glacier Outburst Flood In Tajikistan


(“The lake disappeared and turned to salt…” Melting of glaciers in Tajikistan is having a far-reaching impact. This UN-based program describes how the lives of Tajikistan’s people are being threatened by water loss due to glacier decline. But the impacts of glacier outburst floods can be more directly destructive.)

In Tajikistan, the heat is bringing with it a great decline in high elevation glaciers. Some have already disappeared. It’s a loss resulting in severe impacts to both energy and water security for the country. But perhaps even more disturbing is what happens when water is suddenly released from the dwindling glaciers.

Such was the case with Tajikistan this month. Beginning on July 16, an oppressive heatwave settled over this Central Asian nation. Temperatures rocketed to record levels. Baking its broad mountains — valleys, slopes and glaciers alike.

Crammed between Afghanistan, Pakistan, China, Kyrgyzstan and Uzbekistan, Tajikistan squats along the northwest boundary of the Tibetan Plateau. The upthrust of great glacier-capped peaks tower over this country. Peaks whose heads are loaded with a great volume of ice that is now being forced to rapidly melt.

This month’s record heatwave dealt a terrible blow to that ice. The glaciers, of which Tajikistan boasts 8,492, were already greatly weakened by a 3 degree Celsius temperature increase over the past five years. All it took was the shove of the most recent temperature surge to push some of these to the breaking point. By Tuesday, a great outburst flood had ripped through the mountain valleys of the Central Asia country. The outburst flood waters roared out, overtopping rivers — washing away more than 50 homes, cutting off major roadways, and driving 620 persons into government disaster shelters.

Unfortunately, this most recent climate change mass casualty event may be just one of many. In Tajikistan, a mud dam has developed along the path of major glacial melt. Water pressure is building behind the dam. Should it release, more than 30,000 people will be in the path of the outburst flood.

Risk of Outburst Flooding Near Large Glaciers is a Global Hazard

All throughout the Tibetan Plateau region glacial outburst floods related to human-caused warming are on the rise (see the glacial megaflood). As much as 70 percent of the ice within the great Himalayan glaciers could melt out by 2100 under business as usual fossil fuel burning. The result would be a crescendo of glacial outburst floods followed by a period of drastically increased aridity for the lands around Tibet.

Alaska. Prince William Sound, waterfall flows from under Blackstone Glacier.

Alaska. Prince William Sound, waterfall flows from under Blackstone Glacier.

(The high elevation of glaciers combined with the vastness of their captured water and the often steep grades upon which they perch can generate violent flooding in the event of rapid melt. In many instances, silt from glacial outflows can develop a dam downstream of the glacial flood. Such dams are often unstable and can be subject to catastrophic collapse. In the worst cases, ice dams can form in the interior sections of very large ice sheets — such as those seen in Greenland and Antarctica. Glacial outburst floods due to such melt and ice dam formation in the major ice sheets are catastrophic events of geological scale and impact. Image source: ADT.)

Glacial outburst floods are sudden, powerful, violent, and difficult to predict. They are limited only by the amount of water the glaciers themselves release — ice masses that hold volumes of water often measured in cubic kilometers. The drastic impacts and terrible violence due to this kind of flooding was also recently witnessed during 2013 in Kedarnath, India. And what we see in Tajikistan and India during recent years is, sadly, just a taste of what’s to come in a fossil fuel emissions warmed world.

Finally, in this narrative, we cannot ignore potential glacial outburst flood impacts from melting over the Greenland Ice Sheet and Antarctica. And unlike Tibetan glacial melt, potential outburst flood events issuing from Greenland or Antarctica are a hazard of global scope. Such events would likely be driven by extended periods of rainfall over the ice during summer heating events. An ominous melt-driving phenomena that science is just now starting to track.

Links:

Heatwave + Glacial Melt Forces Hundreds to Flee in Tajikistan

Human Hothouse Death Toll Climbs to 2300 in India

Wet Bulb at 33 C

Freakishly High Temperatures Trigger Melt, Mudslides, Flooding in Tajikistan

The Glacial Megaflood

ADT

Amplified Melt and Flow of Greenland Ice Sheet Driven by Late Summer Rainfall

Hat Tip to TodaysGuestIs

Hat Tip to Colorado Bob

Global Sea Level Rise Going Exponential? New Study Records Big Jump in Ocean Surface Height

From about a thousand years ago through to the mid 19th Century, global sea levels remained remarkably stable. Together with overall global temperatures, sea surface heights stayed at about the same levels until the late 1800s. At that time, an initiation of large-scale burning of oil, gas and coal dumped heavy volumes of greenhouse gasses into the atmosphere. The Earth System began to warm and seas began a slow upward climb.

Hansen sea level rise

(Global sea level rise since 1870. Image source: Dr. James Hansen.)

At first, the pace of sea level rise was minor — only hitting about 0.8 mm per year. But then, by around 1925, the rate of sea level rise more than doubled to 1.9 mm per year. The oceans, which at first only slowly accumulated heat, began a long term warming which eventually extended through almost every depth and region. This pace maintained until about 1992 when the oceans again hit a higher rate of rise at around 3.1 mm per year — a pace that then included a small but ominously growing portion of glacial melt.

Now, it appears that global warming is again pushing sea levels to rise even faster. As, over recent years, a number of ominous indicators pointed toward yet another surge in ocean surface levels.

In south Florida, the pace of  sea level rise at local tidal gauges, by last year, had gone exponential. Along the U.S. East Coast, a sudden jump in sea level during recent years was blamed on a slowing down of the Gulf Stream due to freshwater melt pulses hitting the North Atlantic.

All over the world’s frozen regions, the great land glaciers — especially in Greenland and Antarctica — have been destabilizing. Melting, cracking, and clamoring as their gargantuan, mountain-like forms assembled in an ever-speeding march to the seas. This great rush of freshwater melt and ice is already causing an ocean-threatening slow-down of Atlantic circulation. And in the Southern Ocean surrounding Antarctica an ominous bulge of water near the southern polar zone became an indicator of an increasing rate of melt from some of the largest glaciers on Earth. A bulge that was 2 centimeters higher than the global average along melting and thawing Antarctic shores.

Global Sea Level Rise On Upward Curve?

Recently, the global sea level rise measure — AVISO — also took an unsettling leap. With satellite captures of the world ocean showing a strong surge in sea level rise throughout 2014 and into 2015. A spike that displays vividly as a hockey-stick like jog at the tail end of the measure below:

Aviso sea level rise

(Big spike in sea level rise plainly visible in the AVISO measure. Image source: AVISO.)

It’s an upward jump representing nearly a 1 centimeter spike in the rate of sea level rise over the past six months.

By itself, this jump in sea level would be something to worry over. But new findings paint an even starker picture. For a recent study, headed by Shuang Yi and published on April 30 in Geophysical Research Letters provides evidence that, since 2010, annual rates of global sea level rise have shown a strong uptick. The study, entitled An Increase in the Rate of Global Mean Sea Level Rise Since 2010, notes:

The global mean sea level (GMSL) was reported to have dropped 5 mm due to the 2010/11 La Niña and have recovered in one year. With longer observations, it is shown that the GMSL went further up to a total amount of 11.6 mm by the end of 2012, excluding the 3.0 mm/yr background trend. A reconciled sea level budget, based on observations by Argo project, altimeter and gravity satellites, reveals that the true GMSL rise has been masked by ENSO-related fluctuations and its rate has increased since 2010. After extracting the influence of land water storage, it is shown that the GMSL have been rising at a rate of 4.4 ± 0.5 mm/yr for more than three years, due to an increase in the rate of both land ice loss and steric change.

In short, the study finds an average rate of sea level rise of 4.4 mm per year, or 30% faster than the annual rate from 1992 to 2009, during the period of 2010 to 2013. For these, more rapidly rising, sea levels the study identifies clear causes. The first is an increasing rate of land ice loss. The second is what is termed as ‘steric change’ — a scientific phrase that both identifies ocean thermal expansion due to warming combined with changes in ocean salinity, which also impacts sea surface height.

The April 30 study did not include the more recent sea level rise spike now showing up in the AVISO measure. So, at least for now, sea levels do appear to be sliding up some rather dangerous curves.

Hitting the More Difficult Rates of Sea Level Increase

Such a jump has stark implications for sea level by end century. A 4.4 mm per year rate of rise would equal just less than half a meter of increased sea level within one Century. This compares to the previous rate of rise which would have resulted in a 1 foot global jump within a one hundred year span.

A jump of this kind was, however, predicted with sea level rise by end of this Century expected to hit between 0.5 and 1 meters of increase in the IPCC measure and between 5 and 6 feet in US Coast Guard studies (most studies find a range between 3-9 feet for this Century). The 4.4 mm per year increase is rather ominous in that it already puts annual rates of rise in the IPCC mid-range. An early ramp up with fully eight and a half decades left to go in a Century that will certainly see substantial further increases in global heat accumulation.

Composite

(South Florida 6 meters of sea level rise before [left frame] and after [right frame]. Note that second image is an artist’s rendering based on flood analysis showing what a 6 meter sea level rise would look like for South Florida, should it occur. Image source: Tropical Audobon Society.)

Many planners use the IPCC measure or even more conservative indicators to prepare for sea level rise at their city, county and state shores. And the fact is these indicators may fall well short of reality at the coastlines. A stark circumstance that will become more and more difficult to manage as time moves forward.

Overall, a 2010 ramping in the rate of sea level rise is a bit soon. Similar further jumps leading up to potential worst case 1-4 cm per year levels would initiate a combination of dangerous impacts including untenable rates of rise for coastal regions, severe shocks to ocean circulation systems and overall ocean health, and potentially very dangerous impacts to the world’s weather. To this point Hansen’s paper entitled ‘Greenland Ice Sheet Mass Loss, Exponential?‘ is well worth a (re)read.

Similar Climate Conditions Saw 20 Meter Surges in Sea Level Due to Glacial Melt

With current greenhouse gas levels now in the range of 400-405 parts per million coinciding with substantial jumps in glacial melt and sea level rise, it may be worth taking a look back at times in the geological past when atmospheric heating conditions were similar to those seen today. The last time heat trapping gasses were seen at such high concentrations was at the height of the Pliocene warming 3-5 million years ago. That time saw temperatures in the range of 2-3 degrees Celsius warmer than Holocene averages. It was also a geological period that saw Antarctic and Greenland melt events that pushed seas up to 20 meters higher.

We are exceeding maximum Pliocene atmospheric CO2 thresholds at this time (well exceeding if you count in a 485 CO2 equivalent forcing from all greenhouse gasses added by human beings). And we will almost certainly enter Pliocene warming levels this century. So the melt pressure we are putting on the world’s ice sheets is likely to at least be in the 20 meter range for the (hopefully) longer term.

Links:

An Increase in the Rate of Global Mean Sea Level Rise Since 2010

AVISO

Dr. James Hansen

For Miami, Sea Level Rise Has Already Gone Exponential

An Extreme Sea Level Rise Event Along the Northeast Coast of North America

World Ocean Heartbeat Fading

Antarctic Sea Levels Rising Faster Than the Global Rate

IPCC Sea Level Rise

Tropical Audobon Society

Greenland Ice Sheet Mass Loss, Exponential?

20 Meter Sea Level Rise 5 Million Years Ago

Hat tip to Colorado Bob

Hat tip to Wili

Climate Change’s ‘Waking Giant’ to Set off Rash of Volcanic Eruptions, Tsunamis, Earthquakes?

Calbuco Volcano 2

(Last week’s Calbuco eruption in Chile spews massive cloud of ash and sets off a fireworks display of volcanic lightning. Image source: IFLScience.)

If you look at the geological record of the end of the last ice age, there’s something that crops up that’s more than a little bit disturbing. The approximate 10,000 year period in which 4 degrees Celsius of warming took place was also punctuated by a rash of intense volcanic activity, earthquakes and tsunamis.

It was a time of extraordinary geophysical changes that not only saw the, sometimes catastrophic, melting of massive ice sheets and extreme rises in sea level — it also saw severe geological upheaval. In one region alone — Iceland — instances of volcanic eruption increased 30-50 fold during a period starting about 12,000 years ago. Overall, global spikes in volcanism began near the start of major melt events at around 18,000 years ago and continued on through the Iceland spike at the 12,000 year time-frame, finally tapering off around 7,000 years ago. In the 12,000 to 7,000 year before present period, global volcanic activity was between 2 and 6 times today’s frequency.

Eruption Spikes at Two Volcanoes in Iceland

(A 2010 study found large spikes in volcanic activity at a number of Iceland volcanoes at the end of the last ice age. Image source: How Will Melting of Ice Affect Volcanic Hazards in the 21st Century?)

Geologically active regions around the world and especially in close proximity to melting ice and rising seas saw much greater volcanic eruption, earthquake and tsunami frequency. In particular, California, Europe, and Iceland saw intense volcanic activity spikes. A set of past events pointing toward 21rst Century risks explored in the book: Waking the Giant — How Climate Change Triggers Earthquakes, Volcanoes and Tsunamis.

A leading theory, presented by Dr. Bill McGuire, Hugh Tuffin, J. Maclennan, Peter Huybers and many others is that changes in stress to the Earth’s crust caused by the loss of billions of tons of mass by ice sheets and the displacement of those billions of tons into the world’s ocean system spurred previously stable magma systems into a chaotic displacement. In addition, direct melting of glaciers on slope systems, rising seas and even changes in flood frequency at individual volcanoes, faults and zones of steep topography can result in heightened rates of eruption, earthquakes and instances of slope collapse.

This evidence is causing scientists to investigate feedbacks between warming and potential increases in volcanic activity, earthquakes and tsunamis. A set of events that may also risk the destabilization of undersea methane hydrate stores through the slope collapse and enhanced magma heating mechanisms as well.

Current Events, Raging Pace of Human Warming Bring old Concerns to Light

Though this line of research isn’t new — with modern studies stretching back to the 1950s and with end ice age upheaval research extending for nearly two centuries — recent events have served to underline old concerns. In 2013, the massive eruptions of Iceland’s volcanoes and related disruption of European air travel brought voices like those of Dr. Bill McGuire again to the fore. And, more recently, the massive Tibetan earthquake of this past weekend, resulting in the loss of 4,000 lives, has called into question current human climate change’s role in geological upheaval events.

Nepal Earthquake Dust Flies

(Dust flies through the air during the initial moments of last weekend’s catastrophic Tibet Earthquake. Image source: RT News.)

A report today out in Newsweek notes:

Evidence from the end of the last Ice Age has already shown that the planet’s uneasy web of seismic faults – cracks in the crust like the one that runs along the Himalayas – are very sensitive to the small pressure changes brought by change in the climate. And a sensitive volcano or seismic faultline is a very dangerous one.

Though the Tibetan earthquake was going to happen at some time, it is possible that changes in ice loading on Himalayan glaciers, changes in water volume outflows in the annual Asian monsoon, and sea level rise adding pressure to the geological plates below coastlines — especially in low-lying Bangladesh — had an impact. Such stresses can increase magma chamber production or trigger fault lines to release.

McGuire notes in Newsweek:

Climate change may play a critical role in triggering certain faults in certain places where they could kill a hell of a lot of people. These stress or strain variations – just the pressure of a handshake in geological terms – are perfectly capable of triggering a quake if that fault is ready to go (emphasis added).

One example of where relatively small changes to geological stress can have a big impact on volcanic activity is the Pavlov volcano in Alaska. As McGuire describes, this volcano only erupts during Autumn and Winter. At that time storms ride up into a nearby ocean zone, pushing an average 10cm or 15cm rise in sea level. The added weight of the water is enough to torque the crust and push magma out. Now imagine the kind of extra volcanic activity that could result from 1, 6, or 250 feet of global sea level rise under the raging rate of human-caused warming and you begin to understand the concern.

So the question that many geologists are asking is this: will the greatly exaggerated spike of human warming and related extreme pace of glacial melt, sea level rise, and rainfall changes also result in a greatly exaggerated spike in volcanism, earthquakes, and tsunami events?

Fault lines around the world will be under increased and ever-changing stress. Volcanoes around the world will see the same. The great Ring of Fire is in an ocean-spanning zone. Many, many volcanic, fault and slope systems encompassed in its arc will feel the added weight of sea level rise caused by human warming. In addition, as much or more than the 4 degrees Celsius worth of warming achieved at the end of the last ice age could be seen by the end of this Century.

It’s that kind of very rapid pace of change that has geologists worried with more than a handful thinking that the catastrophic geophysical changes may have already started.

Links:

More Fatal Earthquakes to Come Warn Climate Change Scientists

Could Changing Climates Set off Volcanoes and Quakes?

Waking the Giant: How Climate Change Triggers Earthquakes Tsunamis and Volcanoes

How Will Melting Ice Affect Volcanic Hazards in the 21st Century?

Feedback Between Deglaciation, Volcanism and Atmospheric CO2

The Link Between Volcanism and Deglaciation in Iceland

Avalanche of Dust

Hat Tip to Colorado Bob

More Heat for the Human Hothouse: NASA Shows First Three Months of 2015 Were Warmest on Record

With El Nino firing off in the Pacific and polar amplification pushing to ever-greater extremes in the Arctic, 2015 is following hot on the heels of 2014’s record warmth. A situation that is increasing the likelihood that the 2014-2015 period will feature back-to-back record breaking years.

According to reports from NASA GISS, March of 2015 topped off at third hottest in the global climate record. The reading — at +0.84 C above the 20th Century average — fell just behind March of 2002 (+0.88 C) and March of 2010 (+0.87 C).

A very warm month in a trio of near record warm months that, when combined, exceeded the temperature departure for any January-through-March period in the global climate measure. The average for 2015’s first three months totaled +0.79 C above 20th Century climates, making it the hottest start for any year since 1880. The first three months of 2002 now come in as second hottest at +0.77 C — with 2007 and 2010 tied for the third hottest such period at +0.75 C.

These values are +0.99 C above 1880s averages and about +1.14 C above averages for the cool period at the start of the 20th Century. Ongoing and growing temperature departures representing a very rapid rate of temperature rise — one more than ten times faster than the warming that put an end to the last ice age.

A Heat Signature Consistent With Human-Forced Climate Change

Geographic Temperature Anomalies March NASA 2015

(Geographic disposition of temperature departures by NASA GISS.)

NASA’s geographic temperature anomalies map gives us a sense of the distribution of this extreme and record global heat.

Highest temperature departures occurred in an expansive zone from Northeastern Europe, through most of Siberia, and stretching on up into the high Arctic. This hot zone occurred in conjunction with persistent south to north air flows over the European and Asian Continents. These meridional patterns delivered substantial record heat to the Arctic, contributing to record low sea ice extent measures by end of month. This region also showed monthly anomalies in an extraordinary range of +4 to +7.5 degrees Celsius above average.

A second hot zone along the US and Canadian West Coast occurred in conjunction with a Ridiculously Resilient Ridge pattern and related south to north air flows. This region showed temperature departures in a range higher than 4 degrees Celsius above average and included extreme, 1,200 year, drought conditions for California combined with record heat and wildfires for this broader region.

Throughout the geographic temperature map provided by NASA, we find that most global regions experienced much warmer than normal temperatures — with the equatorial, tropical, and Northern Hemisphere zones showing the greatest departures.

Significant cool departures are either related to an apparent and ocean health threatening AMOC slow-down in the North Atlantic south of Greenland (Rahmstorf), include the Northeastern US and Canada, or involve the broader heat sink in the Southern Ocean. It is a distribution of broad, rapid warming and isolated localized cooling consistent with what global climate models have been predicting for human-forced climate change for many decades now.

These models predicted that the Northern Hemisphere Polar region would warm fastest and first, that the Southern Ocean would draw a greater portion of atmospheric heat into the ocean system, and that land ice melt near Greenland and West Antarctica would generate cold, fresh water flows into the nearby ocean zones and set off localized cooling. Atmospheric cooling, in this case, that would occur in isolation and in the context of a broader and rapidly warming global climate system together with a dangerous warming of the land ice sheets.

Zonal Anomalies Reveal Extraordinary Polar Amplification, Tell-Tale of Southern Ocean Heat Sink

Zonal Anomalies March

(NASA GISS zonal anomalies map for March of 2015)

The NASA zonal anomalies map is also consistent with an extraordinarily strong Northern Hemisphere polar amplification for March. One that jibes with predicted polar warming due to the human heat forcing. Here we find an extreme heat departure in the region of 85-90 North Latitude of +3.2 C for the month. Much of the Northern Hemisphere shows strong heat amplification with values above +1 C and rising in all the Latitudinal zones above 40 North.

All other zonal regions except the noted heat sink in the Southern Ocean show positive, though less extreme, temperature departures.

Overall, these are extraordinary and disturbing heat maps. Observations that validate many of the previous warming predictions. Maps that include the eerie tell-tale of an early Ocean Circulation slow-down in the North Atlantic. A set of observations that point toward a number of rather extreme weather and climate conditions for this year and for the years to follow.

Links:

GISS Surface Temperature Analysis

Atlantic Ocean Circulation Found to Slow Down

World Ocean Heartbeat Fading?

Hat Tip to Kevin Jones

It’s All About Fresh Water — Rapid Sea Level Rise Points To Massive Glacial Melt in Antarctica

It’s all about fresh water. In this case, massive freshwater outflows from the vast glaciers covering Antarctica.

This week, a new scientific report published in the Journal Nature found that from 1992 through 2012 freshwater outflow from Antarctica’s massive glaciers exceeded 400 gigatons each year. An immense flood of cold, fresh water. One that helped push sea levels rapidly higher around the Antarctic continent.

But with glacial melt on the rise and with mountains of ice now inexorably sliding seaward, these freshwater flows may just be the start of even more powerful outbursts to come. And such prospective future events have far-ranging implications for sea level rise, global weather, sea ice, human-caused climate change, and world ocean health.

Flood of Fresh Water Drives More Sea Level Rise Than Expected

The researchers discovered the tell-tale signature of this vast freshwater flood through chemical analysis of the seas surrounding Antarctica. The analysis pointed to a broad and expanding fresh water layer over-riding a warmer, saltier current issuing in from the Southern Ocean.

Since fresh water is less dense than salt water, the freshwater layer expands at the ocean surface causing sea levels to rise more rapidly. Meanwhile, the heating of the deep ocean surrounding Antarctica is thought to result in additional thermal expansion of the water column.

The researchers note:

On the basis of the model simulations, we conclude that this sea-level rise is almost entirely related to steric adjustment [changes that effect atomic spacing], rather than changes in local ocean mass, with a halosteric [salt based] rise in the upper ocean and thermosteric [heat based] contributions at depth. We estimate that an excess freshwater input of 430 ± 230 Gt yr−1 is required to explain the observed sea-level rise. We conclude that accelerating discharge from the Antarctic Ice Sheet has had a pronounced and widespread impact on the adjacent subpolar seas over the past two decades.

Antarctic Sea level Trend

(Rate of sea level rise in the seas surrounding Antarctica since 1992. Aggregate sea level rise is indicated in black. Individual seas data is broken out by color. Image source: Nature.)

Previously, increased rates of sea level rise surrounding Antarctica were thought to have been set off by increasing winds around the continent. The winds were thought to push more water up against the ice faces forming a kind of perpetual, low-grade storm surge. But the current finding provides strong evidence that the source of the sea level rise is due to less dense fresh water over-topping saltier waters flowing in from the Southern Ocean combined with increasing heat along the Antarctic sea bed. And, notably, this is not the first study to find increasing freshwater flows spilling into the Southern Ocean. Last year, a KNMI expedition uncovered similar results.

More Evidence of Large-Scale Melt

The study comes on the back of other recent findings showing that warm water invasion at Antarctic glacier bases had led to more rapid than expected melt and destabilization. In May, two NASA studies showed that a broad section of West Antarctica had destabilized and was sliding at an ever more rapid pace toward the ocean (see reports here and here). These findings held stark implications for global sea level rise as large ice regions of Greenland and West Antarctica, containing enough water to raise seas at least 15 feet, are likely already in a state of irreversible collapse.

 

Regional Anomaly Sea level Antarctic

(Sea level rise anomaly of the region surrounding Antarctica compared with the rest of the Southern Ocean. Red indicates faster than normal sea level rise. Blue indicates slower than normal sea level rise. Image source: Nature.)

This intensifying glacial melt and associated freshwater cap expanding out from the pole has implications — not just for sea level rise, but for sea ice, weather, and world ocean system health.

Impacts For Sea Ice

Large outflows of glacial fresh water may well be involved in the recent observed expansion of sea ice in the zone surrounding Antarctica (see recent related study). Fresh water serves as an insulative cap on the ocean surface preventing warm water from entering the top layer from below. The warm, salty water, in the Antarctic instead pools near the bottom or at the base of the great ice sheets.

Fresh water also freezes at a higher temperature than salt water. So sea ice in an expanding freshwater zone around Antarctica would have naturally higher resiliency even to the rising temperatures now occurring due to human-caused warming. Eventually, however, human heat forcing would overwhelm the ice, but not before a period of related, localized negative feedbacks.

The Iceberg Cooling Effect

The fresh water is a haven for sunlight-reflecting sea ice. It is interspersed with ice bergs from the glacial discharge and the large ice bergs cool the surrounding air. The fresh water layer prevents warm water upwelling from the warm, deep waters surrounding Antarctica. And the leading edge of the fresh water would drive salt-water down-welling along its advancing front. This would push warmer waters toward the ocean bottom, resulting in a kind of heat sink. And this is exactly the kind of dynamic that appears to be ongoing in the Southern Ocean now. These combined impacts are what is known as the ice berg cooling effect associated with large-scale glacial outbursts known as Heinrich Events. And we may well be in the process of setting off one of these geological scale nightmares.

20121230_iceberg_cooling_effect_Hansen_Sato

(Iceberg cooling effect under a mid-range warming scenario when global climate models were set to include the effects of large freshwater outflows from polar glaciers at a fast enough rate to raise seas by 60 cm through 2060 and 144 cm through 2080 [left frames]. Note the cooler zones in the Southern Ocean and North Atlantic adjacent to Greenland. Right frames include mid range emissions/warming scenarios and IPCC projected rates of sea level rise. It is worth noting that the amplifying effects of potential additional ghg release from the global climate system, particularly from Arctic and world ocean carbon stores, are not included in these simulations. Image source: Hansen and Sato.)

For global weather, such events have major implications. Regional cooling in the zone of freshwater outflow would juxtapose regional warming in the southern hemisphere meridional zones. This temperature differential would increase with the strength of the fresh water outflow and the rising intensity of the human-driven warming. The result would be a powerfully intensified storm track. Both the intensified storm track and increased atmospheric moisture loading due to human warming would result in much more powerful weather events than we are currently used to and the potential for catastrophic storms would drastically increase.

Amplifying Feedbacks and a Blow to World Ocean Health

Lastly, the expanding flood of fresh water would result in an increasing stratification of the world ocean system. This stratification would drive warm, salty water toward the ocean bottom and deplete already low oxygen reserves in that region. In addition, the extra heat is more likely to destabilize deep-sea clathrates — releasing methane which will speed in the oxygen depletion of the abyssal waters even as it tips the world ocean system to stop storing carbon and to begin releasing it. A combined feedback that is both an ocean killer and an amplifier to the already extraordinarily powerful human heat forcing mechanism.

Links:

Rapid Sea Level Rise Along Antarctic Margins Due to Increasing Glacial Discharge

Important Role For Ocean Warming and Enhanced Ice Shelf Melt in Sea Ice Expansion

Update on Greenland Ice Sheet Mass Loss: Exponential?

Grim News From NASA: West Antarctica’s Entire Flank is Collapsing

Nature: Human-Destabilized Antarctica Capable of Glacial Outbursts Contributing to Up to 14 Feet of Sea Level Rise Per Century

 

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