New Study Finds that Present CO2 Levels are Capable of Melting Large Portions of East and West Antarctica

If you’re a regular reader of this blog and its comments section, you’re probably more than a little worried about two bits of climate science in particular:

Our understanding of past climates (paleoclimate) and 5-6 C long term climate sensitivity.

And if you’re a frequent returner, you’ve probably figured out by now that the two go hand in glove.

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Looking back to a period of time called the Pliocene climate epoch of 2.6 to 5.3 million years ago, we find that atmospheric carbon dioxide levels were somewhat lower than they are at present — ranging from 390 to 400 parts per million. We also find that global temperatures were between 2 to 3 degrees Celsius warmer than 1880s ranges, that glaciers in Antarctica and Greenland were significantly reduced, and that sea levels were about 25 meters (82 feet) higher than they are today.

(The Totten Glacier is one of many Antarctic land ice systems that are under threat of melt due to human-forced warming. A new paleoclimate study has recently found that levels of atmospheric greenhouse gasses that are below those presently in our atmosphere caused substantial Antarctic melt 4.23 million years ago. Image source: antarctica.gov.)

Given that atmospheric CO2 levels during 2017 will average around 407 parts per million, given that these levels are above those when sea levels were considerably higher than today, and given that these levels of heat trapping gasses are rapidly rising due to continued fossil fuel burning, both the present level of greenhouse gasses in the Earth’s atmosphere and our understanding of past climates should give us substantial cause for concern.

This past week, even more fuel was thrown onto the fire as a paleoclimate-based model study led by Nick Golledge has found that under 400 parts per million CO2 heat forcing during the Pliocene, substantial portions of Antarctica melted over a rather brief period of decades and centuries.

Notably, the model found that the West Antarctic Ice Sheet collapsed in just 100-300 years under the steady 400 ppm CO2 forcing at 4.23 million years ago. In addition, the Wilkes Basin section of Antarctica collapsed within 1-2 thousand years under a similar heat forcing. In total, the study found that Antarctica contributed to 8.6 meters of sea level rise at the time due to the loss of these large formations of land ice.

From the study:

We conclude that the Antarctic ice sheet contributed 8.6 ± 2.8 m to global sea level at this time, under an atmospheric CO2concentration identical to present (400 ppm). Warmer-than-present ocean temperatures led to the collapse of West Antarctica over centuries, whereas higher air temperatures initiated surface melting in parts of East Antarctica that over one to two millennia led to lowering of the ice-sheet surface, flotation of grounded margins in some areas, and retreat of the ice sheet into the Wilkes Subglacial Basin. The results show that regional variations in climate, ice-sheet geometry, and topography produce long-term sea-level contributions that are non-linear with respect to the applied forcings, and which under certain conditions exhibit threshold behaviour associated with behavioural tipping points (emphasis added).

This study began the publication process in 2016 when year-end atmospheric CO2 averages hit around 405 parts per million. By end 2017, those averages will be in the range of 407 parts per million. Even more worrying is the fact that CO2 equivalent forcing from all the various greenhouse gasses that fossil fuel burning and related industrial activity has pumped into the atmosphere (methane, nitrogen oxides, CFCs and others) will, by end 2017 hit around 492 ppm.

As a result, though conditions in Antarctica are presently cooler than during 4.23 million years ago, the considerably higher atmospheric greenhouse gas loading implies that there’s quite a lot more warming in store for both Antarctica and the rest of the world. A warming that, even if atmospheric greenhouse gasses remain at present highly elevated levels and do not continue to rise, could bring about a substantially more significant and rapid melt than during the Pliocene.

Links:

Antarctic Climate and Ice Sheet Configuration During Early Pliocene Interglacial at 4.23 Ma

NOAA ESRL CO2 Trends

NOAA’s Greenhouse Gas Index

East Antarctic Ice Sheet More Vulnerable to Melting than We Thought

Pliocene Climate

antarctica.gov

Hat tip to Spike

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Antarctica’s 4th Largest Ice Shelf is About to Melt Back to its Smallest Area Ever Recorded

These days, there’s a big debate raging in the sciences over the issue of Antarctic melt. On the one side, you have a growing flood of data indicating that many ice shelves are thinning, that surface melt is more prevalent than previously thought, and that glaciers are threatening to destabilize at faster than previously expected rates. On the other side, we still have a number of hold-outs who rightly claim that ice shelves have always calved and that many of the processes we now observe have always been in place.

The scientific messengers sending these various indicators of Antarctic destabilization are cautious not to draw too many conclusions. But the data itself is pretty stark — which has been enough to produce some qualified, if very appropriate, warnings that Antarctica could be tipping toward instability far faster than previously imagined.

(The northern end of a massive rift in the Larsen C Ice Shelf is spawning numerous smaller ice bergs off a larger, Delaware-sized monstrosity. Now, only 3 miles of ice connect this emerging berg to the Larsen C ice mass. Once the berg separates, Larsen C will break back to its smallest area ever recorded. Image source: Project MIDAS.)

Of course the ice shelves named Larsen A and Larsen B existed throughout human times until they were only recently melted by warmth creeping up the along the Antarctic Peninsula in both the air and the water. Meanwhile, the Larsen C ice shelf is about to shatter off a very large 5,800 square kilometer ice berg even as several smaller ice bergs also appear ready to form. This event, which is now imminent in the coming days, weeks, or at most, months, will break the Larsen C ice shelf back to its smallest area ever recorded even as it marks a period of increased instability and risk of ice shelf loss.

For recent scientific assessments show that Larsen C is lowering in the water — an indication that the shelf is thinning. Furthermore, when the gigantic, Delaware-sized, ice berg and its smaller siblings break off they will take with them outer sections of a stabilizing compression arch. The compression arch, somewhat like the arch of a flying buttress, helps to balance structural stresses for the ice shelf. If it were to be compromised in total, according to glacier scientists like Dr. Eric Rignot, Larsen C would soon be adding its name to the list of various ice shelves around the world that have already fallen due to the warming airs and waters produced by human-caused climate change.

(The large ice berg that is presently breaking away from Larsen C appears to have bisected both southern and northern sections of the ice shelf’s stabilizing compression arch [indicated in the upper images by a solid gray line]. Loss of parts of the compression arch are an indication that Larsen C could become considerably less stable in the near future. However, some science indicates that the ice berg presently breaking off from Larsen C does not compromise key stability features. The nearer term future for the greatly reduced Larsen C Ice Shelf is therefore uncertain. Image source: Marine Ice Regulates Future Stability of Large Antarctic Ice Shelf.)

As with most predictive measures, however, the present trend isn’t perfectly clear with regards to the ultimate fate of Larsen C in the near future. Some studies have indicated that the section of ice breaking off is not crucial to the ice shelf’s stability. And the sections of the compression arch that are being taken out are closer to the outer edge of the ice shelf — not representing the key central arch region.

Overall, however, this story for Larsen C isn’t a good one. The shelf is thinning, it is about to reach its smallest area ever recorded, and even the loss of some outer sections of the compression arch are enough for a number scientists to express qualified concern. Larsen C didn’t show this level of instability back in the 90s or 2000s, so the overall trend here is more toward melt and instability for this 4th largest ice shelf in Antarctica.

UPDATE:

As of 7/10/2017 through 7/12/2017, rift formation had finally met open water and the large ice berg breaking away from Larsen C had finally calved. From the Project MIDAS website:

A one trillion tonne iceberg – one of the biggest ever recorded – has calved away from the Larsen C Ice Shelf in Antarctica. The calving occurred sometime between Monday 10th July and Wednesday 12th July 2017, when a 5,800 square km section of Larsen C finally broke away. The iceberg, which is likely to be named A68, weighs more than a trillion tonnes.  Its volume is twice that of Lake Erie, one of the Great Lakes.

Links:

Project MIDAS (and associated scientists)

Antarctica is About to Lose an Enormous Piece of Ice

Marine Ice Regulates Future Stability of a Large Antarctic Ice Shelf

Maximum Buttressing of Larsen C Ice Shelf

Antarctica’s Ice Shelves Thin — Threaten Significant Sea Level Rise

Scientific Hat tip to Dr. Eric Rignot

Scientific Hat tip to Dr. Richard Alley

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

A Flood of Warm Water the Size of 30 Amazon Rivers is Melting One of East Antarctica’s Largest Glaciers

If we’ve learned anything this year, it’s that few of Antarctica’s submerged coastal glaciers are safe from the warming ocean. Places that we once thought wouldn’t be vulnerable to melt for decades or centuries are now starting to feel the heat of rising water temperatures.

The heat comes in the form of great floods of warmer than normal waters running beneath the ocean surface and then eating away at the undersides of ice shelves and sea fronting glaciers. These floods are provided by the warmth forced into the world ocean by rising global greenhouse gas concentrations. And such invasions are happening around Antarctica’s perimeter with increasing frequency. But perhaps the most disturbing such event now ongoing is the present warm water flood running in from the Southern Ocean toward East Antarctica’s Totten Glacier.

calving-front-of-the-totten-glacier

(The melting edge of the Totten Glacier. Image source: Antarctica.gov.)

Totten is a truly gigantic glacier. By itself representing an ice mass equal to that contained in all of West Antarctica’s many glaciers. If large sections of Totten and the associated Aurora Basin were to melt, seas could rise by 12 feet or more. During recent years, researchers identified a great canyon running between 2,000 and 3,600 feet below sea level and stretching six miles wide as a weak point for Totten — whose glaciers sit in an enormous, below sea level rift within East Antarctica.

Researchers recently found that the floating ice shelf buttressing Totten was melting from below. As of 2015, they hadn’t identified a mechanism for this melt. But they had a pretty short suspect list. This year, a new study led by Dr. Stephen Rich Rintoul found that a river of warm water flowing at a rate of 220,000 cubic meters per second was flooding into the vulnerable canyon entrance to Totten’s weak underbelly. The researchers determined that this volume of warm water — equaling a flow rate more than 30 times that of the Amazon River — was enough to account for the observed ice shelf losses over recent years in the range of 60 to 80 billion tons per year.

totten-glacier-basin

(The Totten Glacier of East Antarctica contains about as much ice mass as all of West Antarctica. Its catchment basin is roughly the size of the U.S. Southeast. Much of it sits below sea level. And an ice shelf buttressing the glacier’s largest outlet in a 6 mile wide and 3,600 foot deep canyon is rapidly melting. Once this ice shelf breaks apart, ocean water will flood inland along a reverse slope and the Totten Glacier will increase its rate of movement toward the ocean — significantly speeding rates of global sea level rise. Image source: Australian Antarctic Division.)

The study authors found that:

…several lines of evidence support the conclusion that rapid basal melt of the [Totten Ice Shelf] is driven by the flux of warm [modified circumpolar deep water] into the cavity: the presence of warm water at the ice front, the existence of a deep trough providing access of this warm water to the cavity, direct measurements of mass and heat transport into the cavity, the signature of glacial meltwater in the outflow, and exchange rates inferred from the heat budget and satellite-derived basal melt rates.

Presently, because the ice shelf floats, this melt is not adding to global sea level rise. But the shelf acts like a cork that’s stopping the rest of Totten from flowing into the ocean. And when the ice shelf weakens enough, it will rift and break apart — leaving the massive glaciers behind it exposed to the inrush of warm waters and removing the last major barrier preventing them from bursting out.

Links:

Ocean Heat Drives Rapid Basal Melt of Totten Ice Shelf

Scientists Confirm that Warm Ocean Water is Melting one of East Antarctica’s Biggest Glaciers

One by One, the Flood Gates of Antarctica are Breaking Open

Tottering Totten and the Coming Multi-meter Sea Level Rise

Antarctica.gov

Hat tip to Robert in New Orleans

Did Föhn Winds Just Melt Two Miles of East Antarctic Surface Ice in One Day? 

UPDATE — Cloud Shadows and Bluish Coloration

Layer analysis of the November 27 MODIS satellite image in bands M  1-12 reveals two cloud shadows near the suspect melt pond (an issue that commentators Hendrick and Sammy raise in discussion below). The separate true color image provides comparison and generates the impression that the suspect melt pond is simply a remnant cloud shadow from the kidney-shaped cloud in the M 1-12 band image.

cloud-shadow-vs-suspect-melt-pondnon-corrected-radiance

The cloud shadows move from frame-to-frame providing a further negative confirmation.

Though it is now certain that the large blue blotch in this satellite image is not a melt pond, a bluish coloration appearing over a broad swath of the above region in both the November 27 and November 28 image frames appears to indicate the presence of surface melt. So the downsloping wind related warming may well have produced a more subtle surface melt for this region of East Antarctica.

UPDATE 2 — Small Melt Ponds Visible in Hi Res Satellite Imagery

High resolution satellite imagery confirms surface melt in the region of recent föhn wind activity on November 27 through 28. Note the ponding and bluing in this close-up shot from the S2A instrument.

small-melt-ponds-bluing

(Surface melt visible along the Scott Coast in East Antarctica. Edge of frame for the above image is approximately two miles. Hat tip to Darvince, Tealight and the Arctic Sea Ice Forum. )

So it appears that this abnormal weather/climate event did result in springtime melt in East Antarctica — if not at the scale initially feared. Still rather concerning.

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It’s right there in the satellite image. A swatch of blue that seems to indicate an approximate 2-mile long melt lake formed over the surface of East Antarctica in just one day. If confirmed, this event would be both odd and concerning. A part of the rising signal that melt stresses for the largest mass of land ice on the planet are rapidly increasing.

melt-pond-scott-coast-antarctica-november-27-2016

(Possible large melt lake on the surface of an ice shelf along the Scott Coast appears in this NASA satellite image. The melt lake seems to have formed after just one day during which föhn winds ran downslope from the Transantarctic Mountain Range — providing a potential period of rapid heating of the glacier surface.)

Surface Melt Now Showing Up in East Antarctica

While scientists and environmentalists are understandably concerned about ocean warming melting the undersides of sea-fronting West Antarctic glaciers — resulting in risks for rapid sea level rise for the near future, another consequence of global warming is also starting have a more visible impact on the frozen and now thawing continent. Surface melt, which was hitherto unheard of for most of East Antarctica, is now starting to pop up with increasing frequency.

East Antarctica, according to Stewart Jamieson, a glaciologist at Durham University in the U.K., is “the part of the continent where people have for quite a long time assumed that it’s relatively stable, there’s not a huge amount of change, it’s very, very cold, and so, it’s only very recently that the first supraglacial lakes, on top of the ice, were identified.”

But now, even in austral springtime, we find evidence of surface melt in the satellite record.

On November 27, 2016, what looks like an approximate 2 mile long melt pond appeared in a section of ice shelf along the Scott Coast and just North of the Drygalski Ice Tongue in the region of McMurdo Sound. The suspect lake — which is visible as a light blue swatch at center mass in the NASA-MODIS satellite image above — suddenly showed up in the November 27 satellite image along a region where only white ice was visible before. And it appears in a region of East Antarctica that, before human-forced warming altered the typically-stable Antarctic climate, had rarely, if ever, seen surface melt.

near-freezing-temps-scott-coast-fohn-winds

(Near melting point temperatures appear along the Scott Coast in conjunction with an apparent föhn wind event. Image source: Earth Nullschool.)

The pond shows up coordinate with recorded near 0 C surface temperatures in the GFS monitor for November 26-27 and along with evidence of downsloping (föhn) winds. GFS indicators show downsloping winds gusting to in excess of 50 mph over the period. Such winds have the potential in increase surface temperatures by as much as 14 degrees Celsius in a matter of minutes. And they have, increasingly, produced surface glacial melt events in regions of Greenland and Antarctica during recent years.

Surface Melt as a Feature of Glacial Destabilization

Supraglacial lake is just another word for a surface glacial melt lake. And these new lakes pose a big issue for ice sheet stability. Surface melt lakes are darker than white glacier surfaces. They act as lenses that focus sunlight. And the comparatively warm waters of these lakes can flood into the glacier itself — increasing the overall heat energy of the ice mass.

nasa-greenland-surface-melt

(A NASA researcher investigates a surface melt pond in Greenland. During recent years, these climate change related features have become more common in Antarctica. Image source: NASA.)

But water at the glacier surface doesn’t just sit there. It often bores down into the ice sheet — producing impacts for months and years after the surface lake’s formation. Sub surface lakes can form in the shadow of surface ponds. Transferring heat into the glacier year after year. In other cases, water from these lakes punches all the way to the glacier’s base. There the added lubrication of water speeds the glacier’s flow. All of these processes generate stresses and make glaciers less stable. And it is the presence of surface melt ponds that has been responsible for so much of Greenland’s speeding melt during recent years.

Now, a similar process is impacting the largest concentration of land ice on the planet. And while Greenland holds enough ice to raise sea levels by around 21 feet, East Antarctica contains enough to lift the world’s oceans by about 195 feet. Surface melt there, as a result, produces considerably more risk to the coastal cities of the world.

 

Links:

NASA-MODIS (#ThanksNASA)

These Stunning Blue Lakes Give us New Reason to Worry About Antarctica

Earth Nullschool

New Maps Chart Greenland Glaciers’ Melting Risk

Hat tip to Shawn Redmond (and a special thanks for being the first here to ID the rather odd apparent melt pond forming along the Scott Coast.)

Florida’s Existential Choice For 2016 — Renewables and Climate Responses or Death by Fossil Fuels

People living in the state of Florida have a big problem — their homeland, as it is today, cannot exist for very long if we double down on fossil fuel burning as Donald Trump has proposed. And this situation, in turn, creates a big problem for Trump — he can’t win the 2016 election without Florida’s support. Trump’s vicious combination of climate change denial, anti-renewables policy stances, and attacks on immigrants whose family members may also be displaced by climate change have considerably damaged his chances of capturing the state’s 29 electoral votes. He’s now in a situation where he’s basically reliant on smoke screens and misinformation to convince the voters of Florida to commit what amounts to an electoral suicide.

us-coal-production

(U.S. coal production has been falling since Obama’s election in 2008. As a result, US carbon emissions have plateaued. The kinds of renewable energy that the American people want can continue to generate reductions in greenhouse gasses flooding the environment and give the people living in Florida a fighting chance. But that won’t happen if we elect Donald Trump as President. Image source: Vox and The Energy Information Administration.)

Trump’s Dirty Energy Pledges Would Mean Certain Devastation For Florida

About a week ago, Trump pledged to, in effect, zero out all spending on renewable energy and climate change related science while pushing hard for an expansion of coal, oil, and gas burning if he is elected. Meanwhile, Trump’s energy team is little more than a covey of climate change deniers hand picked directly from the fossil fuel industry. Trump has pledged to kill the EPA, to roll back Obama’s Clean Power Plan, and to drop out of U.S. emissions reductions pledges to the Paris Climate Summit (COP 21).

If you were looking for an example of a perfect storm of the absolute worst climate change and renewable energy related policies, policies that were guaranteed to put the world back on a track toward a devastating business as usual carbon emission — then Trump fits the bill. And to large parts of Florida, Trump’s policy pledges are starting to look a lot like a promise to inflict climate Armageddon on the low-lying state.

(This year, surface melt was observed for the first time in East Antarctica. This new observation points to increased risk of glacial melt from a region that is capable of dramatically raising global sea levels. The people living in low-lying Florida are becoming more and more concerned. And they should be. Video source: Climate State.)

Miami-Dade County sits on the front lines of this rising climate crisis. Already, the city has pledged 400 million dollars to raise streets and upgrade the city’s drainage system. Why? The oceans in Miami have now risen to the point that tides frequently disrupt transportation, flood neighborhoods, and swamp businesses. These upgrades may buy Miami a decade or two or three. But there’s absolutely no way Miami can survive for any longer than this if Trump commits to his policy choices as-is. Even the rosiest rational predictions for sea level rise by the end of this Century put Miami mostly under water well before the year 2100 under the kinds of emission scenarios that a Trump Presidency would commit us to.

Further up the coast, Jacksonville is still reeling from damages inflicted by Hurricane Matthew — a storm made worse both by the record hot Atlantic Ocean and by the added effect sea level rise had on the height of its wind-driven surge of flooding water. Like Miami, Jacksonville is starting to feel the effects of sea level rise. And its likelihood for continued existence this Century would be quite low if Trump’s fossil fuel burning policies were enacted. The story is much the same for pretty much all of Florida’s coastal cities as well as the southern tip of Florida stretching on north to the Everglades. Sea level rise is an existential threat to these regions now. One that will be made far worse if we continue to burn the fossil fuels that Trump is committed to.

Trump Seeks to Kill Renewables While Amendment 1 Attempts to Stymie Solar

Even as Trump is moving to crush renewable energy progress and responses to climate change at the federal level, hurting Florida’s chances of facing down climate threats, the fossil fuel industry and a number of aligned utilities are attempting to stymie solar energy development across the state. Like much of America, residents within Florida are attracted by renewable energy. In fact, a recent poll showed that four out of five voters supported increasing levels of renewable energy development. Home and business owners alike want access to new, clean, independent energy choices. People rightly concerned about the impacts of climate change want more clean energy.

clean-energy-costs

(As the effects of climate change worsened, clean energy costs have been falling. Now costs are so low that financial benefits to individual energy users abound. Fossil fuel industry is acting in increasingly aggressive ways to stifle access by using laws to prevent people from using clean energy sources. Trump is fighting to help these corporations prevent you and your family members from taking advantage of the multiple benefits clean energy provides. Image source: The Whitehouse.)

Since renewable energy is so popular among voters, and even among republicans, fossil fuel special interests often resort to deceptive tactics in order to keep people captive to harmful energy consumption. And this election, utilities have attempted to protect their monopoly power interests by forcing anti-solar Amendment 1 on the state. Amendment 1 aims to open a loop-hole for utilities to charge independent renewable power generators exorbitant fees and to suppress the rate of solar adoption in the state. Amendment 1’s language has been called deceitful by the Union of Concerned Scientists. It’s a proposal that has been put forward by a collection of fossil fuel special interests including Exxon Mobile, Duke Power, The Koch Brothers, Florida Power and Light and others. And if the Amendment passes, it will help to lock Florida in a fossil fueled climate change nightmare. One that is, even now, starting to nibble away at the vital cities that enable the state to function.

Yuge Wave of Climate/Renewable Energy Voters?

With both the future existence of Florida’s cities and access to renewable energy under threat, voters in Florida are turning out like never before. Nationalized Hispanic and Caribbean immigrants whose families may also be forced to seek refuge in the U.S. due to climate change are voting in droves. And the people of the increasingly swamped Miami Dade County are flooding the polls. There, fully 55 percent of registered voters had cast a ballot before election day.

The record turnout in places like Miami-Dade helped bouy the Florida early vote to 6.4 million — more than the total post election day count for the year 2000. This large turnout has come as registered democratic voters lead republicans by 92,000 coming into election day. But first and second generation citizens may well be generating even more of a democratic edge. According to Vice, 86.9 percent more Latinos voted early than during 2012. And a good portion of that 455,000 total are registered as independents and even republicans. Meanwhile, there is some indication that well less than 90 percent of republicans are voting for Trump.

While Trump’s anti-immigrant rhetoric may have helped to generate some of this shift, it is likely that rising climate and energy concerns are also affecting the Florida vote. A poll from earlier this year found that concerns about climate change from Florida residents was on the rise. Fully 81.3 percent of Florida peninsular residents expressed moderate to serious concern about climate change as an issue. And though debate moderators and their mainstream media sponsors failed to raise the critical issues of climate change and renewable energy in the televised match-ups between Clinton and Trump, Clinton frequently harangued Trump for his noted extreme degree of climate change denial. Furthermore, Trump’s own statements and policy choices have produced enough ripples in the media to generate a general understanding that Trump is fighting against popular advances in renewable energy while stifling responses to climate change in a state where people are becoming increasingly aware that they’re under the gun. Together, these underlying political forces are likely to sap voters away from Trump in a state he must win to secure the 2016 election.

Let’s hope that happens. The future of Florida and so many other important things hangs in the balance.

Links:

Vox

The Energy Information Administration

Trump to Zero Out Clean Energy Funding

Climate State

U.S. Voters Want Renewable Energy

The Whitehouse

Four Reasons to Vote No on Anti-Solar Amendment 1

Florida Early Vote Beats Entire 2000 Turnout

Floridians are More Concerned About Climate Change

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.

*****

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

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

Current Sea Level Rise is Faster Than at Any Time in Last 6,000 Years

Antarctica October 14

(NASA satellite shot of Antarctica on October 13 of 2014. Recent scientific papers point toward a vicious cycle of Antarctic glacial melt. Expanding sea ice results from increased cold, fresh water outflows from melting land-anchored glaciers spreading out along the ocean surface and protecting the floating ice. Meanwhile, rapidly warming waters concentrate in a layer beneath the ice to further accelerate melting of the giant glaciers’ bases. Image source: LANCE-MODIS.)

With fewer and fewer logical straws to grasp for plausibly denying an obvious and inexorable warming of the global climate system, climate change deniers have resorted to pointing toward an expanding veil of sea ice near Antarctica as ‘proof positive’ that global warming really isn’t happening.

But recent scientific papers reveal that what may well appear to be a soothing light at the end of an imaginary cooling tunnel is more a freight train of global heat aimed directly at the ice sheets’ weak underbellies. For the last time the cool, fresh waters of an initial Antarctic melt expanded out along the surface, likely temporarily enhancing the range of sea ice as well, below-surface warmth ran beneath the ice and rapidly melted sea-fronting glaciers, leading to a sea level rise of about 14 feet in just one century.

In essence, the expanding skein of ice and fresh water concentrated warmth where it was needed least — at the bases of massive glaciers submerged in hundreds of feet of warming water. The heat melted the glacier from the bottom up, floated the glaciers and then flooding further inland beneath the ice to do still more damage.

And it is the start of just this process that we are witnessing now. How fast it proceeds will be critical to the rate of sea level rise going forward.

As for all that extra sea ice? Well, that’s merely the last gasp of coolness running along the surface waters — sent out by the dying glaciers.

Current Sea Level Rise Unprecedented in 6,000 Years

Past and future sea level rise WG 1 AR 5

(Past and future sea level rise as shown in this IPCC AR5 WG1 graphic. Note the steady rate of sea level increase beginning at around 1880 and continuing on through the 21st Century. Also note the recent uptick in observed sea level rise together with end 21st Century projections by the IPCC. It is also worth noting that many still consider the IPCC projections to be a bit too conservative, especially when considering business as usual projections of 3-5 C or greater warming by the end of this century. Image source: IPCC.)

It is likely that we are just in the first stages of such a catastrophic process of ice sheet decline. A process that will last for centuries, but one that is already having a profound impact on the world’s oceans and coastlines.

For a new study, published yesterday in the Proceedings of the National Academy of Sciences, has found that sea level rise over the past century is the fastest it has been since the end of the last ice age — when vast surges of water erupted from the melting glaciers.

The study, which compiled over 1,000 measurements of sea level over the past 35,000 years from sediment samples, found that at no time during the most stable period of the Holocene have seas ever risen so fast as they are now rising. This 6,000 year period saw no increase or decrease in sea level exceeding 15-20 centimeters over 200 year time-frames. But during the 100 years from 1900 to 2000, seas rose by 20 centimeters, more than doubling highest rates of variance during the last 6,000 years.

Increasing Heat Melts Glaciers, Swells Seas

The increases to sea level are a result of added ocean and atmospheric heat. A warming pushed ever-higher by a rapidly expanding heat-trapping gas emission.

Such direct heating of the ocean causes water to thermally expand. The added atmospheric and ocean heat also goes to work melting glaciers at the surface and where the glaciers contact the warming seas. These glaciers, in turn, add great volumes of water to the world’s oceans. The upshot of a 0.6 degree Celsius warming of the atmosphere and near surface world ocean during the 20th Century.

But both this heating and melt were just the start. For the atmospheric warming hit 0.8 C by the early second decade of the 21st Century even as top 700 meter ocean heat content spiked to unexpectedly high levels. Meanwhile, forecast rates for rising seas and temperatures are even more extreme for the coming years and decades.

Sediment plumes from Greenland Sep 2014

(Tell-tale 100 km long plumes of sediment carried out from beneath Greenland’s glaciers by floods of melt water as seen in this NASA satellite shot from September of 2014. Surface melt from Greenland tunnels through the ice sheet base. Once there, it flows from beneath the ice sheet and out into the oceans — carrying with it loads of sediment flushed from beneath the glacier. Melt from both the Greenland and West Antarctic ice sheets has greatly increased during recent years. Image source: Earth Observatory.)

Current Rate of Sea Level Rise More than 60% Faster Than 20th Century Mean

If the average rate of sea level rise was 2 mm per year during the 20th Century, the past two decades have witnessed a more than 60% rate of increase over even that unprecedented rate. For current sea level rise measures show a 3.27 mm per year increase.

Most scientists expect an ever more extreme rate of atmospheric warming over the 21st Century to ramp this already rapid rate higher — with annual increases likely to exceed 1 cm before 2100 arrives. Such rates would push end 21st Century sea level rise well into the end ice age range of 1.2 meters every 100 years — with chances for even greater rates of increase going forward.

The IPCC has identified a likely sea level rise in the range of 2-3 feet by the end of this Century (60-100 cm), with many outside analysts identifying a range between 2-9 feet (60-300 cm) as possible given the potential for 3-5 C warming under business as usual fossil fuel emissions (Researchers at the Neils Bohr Institute recently established a range from 2-6 feet but note that sea level rises of 80 cm [2.5 feet] are most likely this century and increases of greater than 6 feet have a probability of less than 5% through 2100).

Sea level rise 1993 to 2014

(Current rate of sea level rise as measured by AVISO. Note the 3.27 mm per year rise that has been ongoing since 1992 with an increasing flux beginning around 2010. Image source: AVISO.)

For context, current global CO2e atmospheric heat forcing is in the range of 481 ppm CO2e. The last time CO2 equivalent heat forcing hit such levels, millions of years ago, oceans were 75-120 feet higher and temperatures were about 3.6 C warmer than they are today.

It is also worth noting that it took 10,000 years for the Earth to warm by about 5 C at the end of the last ice age. Current and expected human greenhouse gas emissions (without a rapid transition to renewable energy sources and zero carbon civilizations) could well achieve a similar level of warming in just 180 to 270 years (1880 to 2150) — a pace more than 30 times faster than what was witnessed then.

Links:

Sea Level and Global Ice Volumes From Last Glacial Maximum to the Holocene

New Study Finds 3-4 Meter Sea Level Rise May Be Imminent

It’s Worse Than We Thought — New Study Finds Earth is Warming Far Faster than Expected

LANCE-MODIS

Earth Observatory

AVISO

New Study Finds 3-4 Meter Sea Level Rise From Antarctica May be Imminent

Ocean stratification. A condition characterized by the separation of layers of water of different temperatures and chemical make-up. A condition that has serious impacts to the geophysical nature of the worlds oceans, to the ability of oceans to support life, and to the stability of the vast glaciers of Antarctica — whose faces plunge as deep as hundreds of feet into the Southern Ocean.

In the Antarctic, today, what we see is a cold surface layer and a heating bottom layer. The cold surface layer is fed by an expanding pulse of chill, fresh water issuing from the melting glaciers of Antarctica. Over the years it has become more uniform, sequestering cold near the surface as warmth builds up in the depths below. The deeper hot layer is fed by warmer water issuing in from the tropics and heated to temperatures not seen for tens of thousands of years. This hot water bears a heavy burden of salt. So it is denser and it dives beneath the expanding fresh water layer. The insulating fresh, cold water layer prevents mixing between the bottom layer and the surface. Such mixing would cool the bottom layer. But instead the heat builds and builds and builds.

Difference in Ice mass Between now and last glacial maximum

(Antarctica — visual difference in ice mass between now [right] and last glacial maximum [left]. By mid century, atmospheric greenhouse gas concentrations driven by humans could be high enough [550 ppm CO2e+] to melt all the remaining ice upon this now-frozen continent. Image source: NASA/Goddard Space Flight Center.)

Ocean currents bring the deep, hot water in contact with the base of Antarctica’s massive glaciers. And this intensely focused heat engine goes to work to rapidly melt the ice.

It is this condition of ongoing and intense melting of the ice sheet’s bases that terminate in faces of ice cliffs, hundreds of feet high and deeply submerged in the sea, that is driving the irreversible collapse of many glaciers in Antarctica. Already, due to this irreversible fall, the entire flank of West Antarctica is under collapse — locking in at least three feet of sea level rise from this region alone going forward.

But now, a new study finds that these conditions — the same conditions we observe today — led to the release of enough glacial ice from Antarctica alone at the end of the last ice age to raise sea levels by 3-4 meters (10-13 feet) in just 1-3 centuries.

From Nature Communications:

“The reason for the layering is that global warming in parts of Antarctica is causing land-based ice to melt, adding massive amounts of freshwater to the ocean surface,” said ARC Centre of Excellence for Climate System Science researcher Prof Matthew England an author of the paper.

“At the same time as the surface is cooling, the deeper ocean is warming, which has already accelerated the decline of glaciers on Pine Island and Totten. It appears global warming is replicating conditions that, in the past, triggered significant shifts in the stability of the Antarctic ice sheet.”

The last time this happened was 14,000 years ago as the Earth slowly warmed out of the end of the last ice age. But the result was anything but gradual:

“Our model simulations provide a new mechanism that reconciles geological evidence of past global sea level rise,” said researcher UNSW ARC Future Fellow Dr Chris Fogwill.

“The results demonstrate that while Antarctic ice sheets are remote, they may play a far bigger role in driving past and importantly future sea level rise than we previously suspected.”

“The big question is whether the ice sheet will react to these changing ocean conditions as rapidly as it did 14,000 years ago,” said lead author Dr Nick Golledge, a senior research fellow at Victoria’s Antarctic Research Centre.

These are critical questions. Ones that have serious impacts for the more than 700 million people now living within 10 meters of current sea level.

Antarctic Ice Shelf Thickness Changes

(Antarctic Ice Shelf thickness changes. Note the thinning of almost all the ice shelves along the margin of Antarctica. Ice shelves anchor interior ice, keeping it from rushing out through deep channels into the Southern Ocean. Rapidly thinning ice shelves is a precursor to glaciers rushing toward the sea. Image source: Nature Pritchard et al. 2012)

To this point it is worth noting that the pace of warming 14,000 years ago was on the order of 0.05 degrees Celsius each century. The current pace of human-driven warming over the past century was 20 times faster. This century, the warming is predicted to be as much as 500 times faster (3-5 C warming by 2100). So the question may we be — will Antarctica respond as ‘slowly’ as it did at the end of the last ice age? Slow as in ice outbursts that lead to sea levels rising by as much as 14 feet during one century.

Links:

Change Antarctic Conditions Could Trigger Steep Rise in Sea Levels

Antarctic Contribution to Meltwater Pulse 1A From Reduced Southern Ocean Overturning

Weighing Change in Antarctica

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

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

Antarctic Ice Sheet Loss Driven by Basal Melting of Ice Shelves

(Hat Tip to Colorado Bob)

 

 

 

 

 

Greenland Ice Loss Increases Fivefold From Late 1990s, West Antarctica Not Far Behind

In the early 1990s, it would have been hard to imagine the rates of glacial ice loss we are seeing now.

There were few ways to accurately measure the Greenland Ice Sheet’s mass. Snow fell, glaciers calved. But observations seemed to show that the great, cold ice pile over Greenland was in balance. Snow gathered at the top, glaciers calved at the edges, but human heating of the atmosphere had yet to show plainly visible effects.

At that time, climate scientists believed that changes to the ice, as a result of human caused heating, would be slow and gradual, and would probably not begin to appear in force until later in the 21st Century.

Greenland Jacobshavn July 30 2014

(Extensive surface melt ponding, dark snow near the rapidly melt Jakobshavn Glacier on the West Coast of Greenland in early August of 2014. Image source: LANCE MODIS.)

Ice Sheet Response Starts Too Soon

By the late 1990s, various satellites had been lofted to measure the gravity, mass and volume of structures on the Earth’s surface. These sensors, when aimed at the great ice sheets, found that Greenland, during a period of 1997 to 2003 was losing mass at a rate of about 83 cubic kilometers each year.

This rate of ice loss was somewhat small when compared to the vastness of the ice sheet. But the appearance of loss was early and, therefore, some cause for concern. More monitoring of the ice sheet took place as scientists continued their investigation, for it appeared that the ice sheet was more responsive to human warming than initially believed.

A Doubling After Just Six Years

By 2009 another set of measures was in and it found that the six year period from 2003 to 2009 showed a near doubling of ice mass loss from the Greenland Ice Sheet. Rates of loss had jumped from 83 cubic kilometers each year to around 153 cubic kilometers. The doubling caused consternation and speculation among climate scientists. Greenhouse gas heat forcing was rapidly on the rise and the world’s oceans were warming faster than expected as human emissions continued along a worst case scenario path. It appeared that the ocean was delivering heat to the ice sheet bases even as atmospheric warming was melting larger areas upon the ice sheet surface.

These changes to the massive ice sheets were occurring far more rapidly than previously considered.

Edge of Greenland Ice Sheet

(Hundreds foot high edge of the Greenland Ice Sheet in Kangerlussuaq as seen at the end of a long valley and across a cold estuary. Image source: EISCAT Scientific Association.)

The potential for a 3, 6, or even 9 foot or more sea level rise by the end of the 21st Century was raised. Perhaps even more ominous, global climate models were showing that rapid ice melt in Greenland and West Antarctica, should it occur, would play havoc with world weather systems. It was this jump in ice loss, in part, that spurred climate scientist and then head of NASA GISS, Dr. James Hansen to write his book The Storms of My Grandchildren as a warning that rapid mitigation in human greenhouse gas emissions along with a stabilization of atmospheric CO2 at 350 ppm would probably be needed to prevent severe consequences from human-caused warming.

But humans kept emitting at a break-neck pace, spending far more money to build coal, gas and oil based technology, than to reduce energy consumption through efficiencies or behavioral change or to invest in alternatives like wind and solar.

Melt Rates Surge Yet Again

And so, by January of 2014, heat forcing had continued to accumulate at a very rapid pace. CO2e heat forcing had spiked to 481 ppm, enough to melt the entire Greenland Ice Sheet and much of Antarctica as well, if maintained or increased over a long period.

And the Greenland Ice sheet was, indeed, melting at an ever faster clip. For the most recent assessment found that the loss rate from Greenland had again more than doubled — hitting a 375 cubic kilometer per year average during the period of January 2011 through January of 2014.

Greenland Ice Sheet Elevation Change

(Greenland Ice Sheet elevation change in meters as found in a recent report by the Alfred Wegner Institute. Note that all Greenland edge zones are now experience elevation losses. Due to higher elevations at the center of the ice sheet, elevation loss at the edge has an effect that speeds ice sheet motion toward the sea. The effect is similar to pushing down the edge of a plastic swimming pool, but on a much larger scale and with somewhat slower moving ice.)

It was an extraordinary rate of melt now 4.7 times faster than in the period from 1997 to 2003 and 2.5 times faster than during 2003 to 2009. But, likely, it is but one more milestone on the path to even faster melt.

The same study that found the Greenland melt acceleration also saw a tripling of the melt rate of West Antarctic since 2003 to 2009. Together, the ice sheets were found to contribute a combined mass loss of 503 cubic kilometers per year between Greenland and West Antarctic. This vast, and still apparently rising, loss now meant that the two great ice sheets were contributing at least one millimeter per year to sea level rise.

Likely Grim Future For Sea Level Rise

It is likely that mass rate losses will continue to increase until some kind of break or negative feedback comes into play. Similar rates of melt increase would mean an annual 5-8 millimeter sea level rise by 2035 due to Greenland and Antarctic melt on top of a 2-3 millimeter sea level rise from thermal expansion of the oceans and from other melt sources. But even taking into account the cooling effect at the ocean surface from ice melt and fresh water floods, one could easily envision the feared 1-3 foot sea level rise by sometime near mid century and the even more concerning 3-9 foot sea level rise amidst a very intense battle between hot and cold weather systems through to century’s end.

As of 2014, it appears the conditions leading up to the warned of “Storms of My Grandchildren” are well in play and rapidly building.

Links:

Alfred Wegner Institute: Elevation Change of the Greenland Ice Sheet

Greenland Ice Loss Doubles From Late 2000s

LANCE MODIS

The Storms of My Grandchildren

EISCAT Scientific Association

Hat Tip to TodaysGuestIs

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