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Record Hot Arctic: NOAA’s 2015 Report Card Shows Signs of Failing Climates

In NOAA’s most recent annual Arctic Report Card, the records just keep falling as the litany of global warming related events appearing throughout the far north continued to crop up with ever-more dizzying frequency…

(NOAA’s Arctic report is a stark expose of the state of the Arctic climate. What we view now is a system undergoing a rapid and dynamic transition from its previously stable state to something that is entirely new and alien to human civilization. Video source: NOAA.)

The 12 month period of October 2014 to September 2015 was the hottest one year time-frame since record keeping began for the Arctic back in 1900. As a result of these record warm temperatures, Arctic sea ice during the Winter hit its lowest maximum extent ever seen. Summer sea ice extent was likewise greatly reduced hitting its 4th lowest extent ever recorded. Old, thick sea ice which represented 20 percent of the ice pack in 1985, has precipitously declined to a mere 3 percent of the ice pack today. Snow cover also took a hit, declining to its second lowest extent on record during 2015 and striking a range of 50 percent below the typical average for the month.

Overall warming of the Arctic is at a much more rapid pace than the rest of the world. This accelerated pace of warming is due, in large part, to loss of snow and sea ice reflectivity during the Spring and Summer months. As a result, more heat is absorbed into dark land and ocean surfaces — a heat that is retained throughout the Arctic over longer and longer periods. And, though NOAA doesn’t report it in the above video, overall higher concentrations of greenhouse gasses like methane and CO2 in or near the Arctic region also contribute to a higher rate of warming (see NOAA’s ESRL figures). In a world that is now rapidly proceeding beyond the 400 ppm CO2 and 485 ppm CO2e threshold, this is exactly the kind of Northern Hemisphere polar amplification we would expect to see.

Warm Winds, Greenland Ice Sheet Melt, and Mass Migrations

NOAA notes a marked change in the distribution of life with mass migrations of all life forms well underway in and around the Arctic. Transitions and disruptions are most highly visible among marine mammals like walruses and polar bears — who are increasingly forced to live on land during the summer months. Meanwhile, an ever-broadening number of non-native fish are invading the Arctic from the south.

south-to-north-weather-pattern-alaska

(South to north weather patterns, like the one featured above, have increasingly drawn warm winds up and over Alaska. An anomalous new weather feature that has merited comment in NOAA’s recent annual Arctic report card. Image from “Arctic Heatwave to Rip Polar Vortex in Half”.)

NOAA also links the warm wind invasion events reported on widely here to the second worst wildfire season ever to strike Alaska in 2015. A dipole feature that displays teleconnections between Arctic snow and ice loss, the hot blob of water in the Northeastern Pacific, and the persistent trough that prevailed over the US East Coast during the Winter of 2014-2015.

Finally, Greenland Ice Sheet surface melt hit a maximum coverage above 50 percent for the first time since the extreme melt that occurred in 2012. NOAA notes that the amount of ice delivered to the ocean by glaciers also increased across Greenland even as recent studies continued to find an increasing prevalence of glacial destabilization and acceleration among Greenland’s ocean-terminating glaciers.

NOAA concludes: “Taken together, 2015 shows a continuing set of major changes in the Arctic.”

Links:

NOAA’s Arctic Report Card

Major Arctic Wildfire Outbreak

NOAA ESRL

Arctic Heatwave to Rip Polar Vortex in Half

El Nino, Polar Amplification or Both?

Hat Tip to Alexandr

 

 

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When the Great Ice Sheets Start Going Down — Approaching the Age of “Storms”

The great ice sheets are melting with increasing velocity. Melt ponds are forming over Greenland, then pounding heat down through the ice like the smoldering hammers of ancient Norse fire giants. Warming mid-depth ocean waters are eating away at the undersides of Antarctica’s great ice shelves. Pools of fresh water are expanding outward from the bleeding glaciers, flooding the surface zones of the world’s oceans. Sea level rise rates have jumped to 4.4 millimeters per year (see study here). And the North Atlantic Overturning Circulation (AMOC) is slowing down.

Ice mass loss all glaciers

(Accelerating ice mass loss from Antarctica, Greenland and other continental glaciers and ice caps [GICs]. Image source: Geophysical Research Letters.)

Keeping all this in mind, let’s talk a little bit about the ugly transition to phase 2 climate change. A transition it now appears we’re at the start of. The — you should have listened to Dr. James Hansen and read The Storms of My Grandchildren — phase of climate change. The awful, long, stormy period in which the great glaciers really start going down.

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In an effort to organize how human-caused climate change may proceed, it helps to break the likely progression of human-caused climate change down into three basic phases. For this simplification we have phase 1 — polar amplification, phase 2 glacial melt and storms, and phase 3 — runaway hothouse and stratified/Canfield Oceans. For this article, we’ll focus mostly on phase 1 and 2.

Phase 1 — Polar Amplification

During the first phase, human greenhouse gas emissions gradually add heat to the atmosphere. This causes general warming that is most intense at the polar regions, especially in the Northern Hemisphere. Called Polar Amplification, this added heating at the poles occurs due to greenhouse gasses’ ability to increase the atmosphere’s heat trapping efficiency at night, when the sunlight angle is low, or during periods of dimmer light (cloudiness etc). In addition, snow and ice melt cause albedo loss at the poles and greenhouse gasses sequestered within frozen carbon stores may release during warming as ice thaws adding another kick to polar amplification (amplifying feedbacks). Due to lower volumes of continental ice, more low-albedo land mass, more vulnerable carbon stores, and closer proximity to human greenhouse gas emissions sources, the Northern Hemisphere polar zone is most vulnerable to increased rates of warming during phase 1 climate change.

Weather impacts during phase 1 include a slowing down of the jet stream due to loss of polar ice, a multiplication of slow moving weather systems, an increasing prevalence of drought and heavy rainfall events, and a slow ratcheting of the intensity of powerful storms. Phase 1 continues until ice sheets begin to become heavily involved and melt outflows greatly increase. At that point, we begin a transition to a more unstable period of human-caused climate change — phase 2.

Phase 2 — An Age of Storms

During phase 2, ever-increasing volumes of cold, fresh ice and water pulse out from the world’s glaciers. In essence, the great mountains of ice really get moving and there’s nothing left to stop them. The glacial heat content has reached a critical point and the glaciers start moving and crumbling on a massive scale. A seaward avalanche that has essentially become unstoppable due to basic inertia.

Due to highest levels of ice concentration, the regions seeing the greatest impact are areas adjacent to Greenland and Antarctica. Cold, fresh water and ice hitting these local ocean zones have numerous influences. The first is that the local fresh water acts as a lid on ocean-to-atmosphere heat transfer. As a result, atmospheric temperatures in the region near large glacial melts will tend to cool. Warm, saltier surface waters near the glacial outflows are pushed downward by the lighter, fresh water — heating the ocean bottom zone and continuing to melt the underbellies of sea facing glaciers. Ultimately, the meridional ocean circulations in the North Atlantic and in the Southern Ocean are cut off.

Deep water formation is driven toward the equator. This stops heat transport toward the poles in a number of regions resulting in equatorial heat amplification. Meanwhile, the impact of the fresh water ocean lid results in local atmospheric cooling near the glaciers — a counter-trend to a larger global warming.

Weather-wise, we see a reverse of the trends first apparent during phase 1. The cooling of surface zones near the great glaciers puts a damper of phase 1 polar amplification. Meanwhile, the southward progression of fresh surface waters shuts down the oceanic coveyors transporting heat into the polar zones. As a result we see heat building up through a kind of ocean heat transport train-wreck in low latitude regions near the equator. The combined equatorial heating and near glacier cooling increases temperature gradients and amplifies the storm track.

20121230_iceberg_cooling_effect_Hansen_Sato

(Model runs showing temperature anomalies under A1B [near RCP 6.0] scenario warming with 0.6 meter global sea level rise from glacial outflows by 2065 and 1.44 meter global sea level rise by 2080 vs only thermal expansion based sea level rise [right frame images]. Note that A1B implies about 550 ppm CO2 — a bad scenario but no-where near the worst case. Also note that these models do not include carbon store response feedbacks. Finally, the models were adjusted by adding fresh water outflows from glaciers, so this is not a prediction of rate of sea level rise, only a projection of atmospheric impacts under a given melt and ghg scenario. Image source: Greenland Melt Exponential?)

In the Northern Hemisphere, the North Atlantic sees the greatest counter-trend cooling influence in atmospheric regions due to glacial melt. Meanwhile, Arctic regions continue to see (somewhat slowed) warming conditions. The result is a shift of the center of cold air to an off-set zone more toward Greenland and a screaming storm track running oblong over the polar zone and centering over a trough in the North Atlantic. Amazing temperature differentials between the continents, the Polar zone, Greenland, the North Atlantic, the equatorial Atlantic and Africa result in the potential for continent-sized storms packing the strength of hurricanes according to a recent study by Hansen.

The storms would spin up as the unstable cold air over Greenland ravels and unravels in great frontal wings of cold air encountering the hot air roiling at the equator and building in sections of the Arctic and over the continents. Tropical storms forming adjacent to cold core storms would increase the potential for hybrid storm events. And extreme temperature gradients would provide high octane atmospheric fuel for baroclinic systems. Finally, the great melt pulses themselves would supply periods of high global thermal variance. The pre melt pulse times would see rapid warming, while the post melt pulse times would see cooling. This up-down would periodically load and then wring the global atmosphere of moisture, resulting in high risk for extreme deluge events.

Heating the Deep Ocean Sets Stage for Phase 3

Meanwhile, heat at the ocean surface is driven toward the deep ocean by the fresh water melt pulses issuing from the glaciers. So the melt outflows and storms of phase 2 climate change act as an amazing mechanism for atmosphere-to-ocean heat transfer. Which is really bad news for the health of the world ocean system.

This phase 2 climate change age of storms lasts so long as large glacial outflows still issue from Greenland (in the North) and Antarctica (in the South). Since even under the most rapid pace of human-caused warming it would take hundreds of years for the great ice sheets to go down, what we are looking at is a period of possibly centuries. Avoiding phase 2 climate change, on the other hand, involves avoiding rapid destablization of Greenland and Antarctica’s ice sheets. An issue we may have already pushed too hard to prevent at least some of these storm, ocean, and weather destabilization impacts.

As for phase 3 climate change — that’s a transition to a runaway hothouse and a stratified/Canfield Ocean state. And we really don’t want to see that either. But before we get there, it’s a transition to an age of glacial melt and tremendously potent storms.

Links:

Hat Tip to Colorado Bob

Why Greenland’s Huge Melt Lakes are Vanishing

Global Sea Level Rise, Ice Melt, El Nino

An Increase in the Rate of Sea Level Rise Since 2010

What’s Going on in the North Atlantic?

Geophysical Research Letters

Greenland Melt Exponential?

The Storms of My Grandchildren

Smokey Greenland Sees Another Summer of Substantial Melt

Smoke From Canadian Wildfires Near Greenland

(Smoke from Record Northwest Territory Wildfires on August 1, 2014 crossing Baffin Bay and the West Coast of Greenland. Image source: LANCE-MODIS.)

According to our best understanding of paleoclimate, at current greenhouse gas levels of 402 parts per million CO2 and 481 parts per million CO2e, the Greenland Ice Sheet eventually melts out entirely. It’s a level of atmospheric heat forcing we’ve already set in place, a level that keeps rising at a rate of about 2.2 parts per million CO2 and 3 parts per million CO2e each and every year due to our ongoing and reckless carbon emissions. And it’s a level that is already starting to receive substantial additions from destabilizing permafrost carbon together with likely increasing releases from sea bed methane stores.

In this, rather stark, geological, climatological and physical context, we ask the question — is it possible for us to stop a wholesale collapse of Greenland’s ice? And we wonder, how long can the ice sheet last as human greenhouse gas forcings together with ongoing releases from some of Earth’s largest carbon stores continue to rise?

Greenland Jacobshavn July 30 2014

(Extensive melt ponds, Dark Snow on West Face of Greenland Ice Sheet near the Jakobshavn Glacier on July 30, 2014. Extensive darkening of the ice sheet surface, especially near the ice sheet edge, is resulting in more solar energy being absorbed by the ice sheet. Recent studies have shown that edge melt results in rapid destabilization and speeds glacier flows due to the fact that edge ice traditionally acts like a wall holding the more central and denser ice pack back. Notably, the Jakobshavn is currently Greenland’s fastest glacier. Image source: LANCE-MODIS.)

For ultimately, our ability or inability to rapidly mitigate and then draw down extreme levels of atmospheric greenhouse gasses will provide an answer these key questions. And whether we realize it or not, we are already in a race against a growing Earth Systems response that may eventually overwhelm our efforts, if we continue to delay for too long.

But there’s a lot of inertia in the ice. It represents aeons and aeons of ancient cold locked in great, mountain-high blocks. And its eventual release, which is likely to continue to ramp higher and higher this century, is bound to result in a temporary and weather-wrecking outrush of that cold causing dramatic swings in temperature and climate states to be the rule of the day for Greenland as time moves forward.

Melt Ponds Zachariae Glacier July 25, 2014

(Large melt ponds, extensive surface water over Zachariae Glacier in Northeast Greenland on July 25 of 2014. For reference, the larger melt ponds in this image range from 1 to 4 kilometers at their widest points. The Zachariae Glacier sits atop a deep, below sea level channel that runs all the way to a massive below sea level basin at the center of the Greenland Ice Sheet. This Glacier is now one of more than 13 massive ice blocks that are moving at ever increasing velocity toward the ocean. Image source: LANCE-MODIS)

So we should not expect any melt to follow a neat or smooth trend, but to instead include large variations along an incline toward greater losses. In short, we’ve likely locked in centuries of great instability and variability during which the great ice sheets are softened up and eventually wither away.

Another Year of Strong Greenland Melt

In the context of the past two decades, the 2014 summer melt has trended well above the 30 year average in both melt extent and surface mass losses. Though somewhat behind melt during 2012, 2014 may rank in the top 10 melt years with continued strong melt in various regions and an overall substantial loss of ice mass.

Surface melt extent appears to be overall above 2013 values, ranging well above the 1981-2010 average, but significantly below extents seen during the record 2012 melt:

Greenland Melt Summer 2014Greenland melt 2013

Greenland Melt 2012

(Last three years of surface melt extent with the most current melt graph for the 2014 melt season at the top and the preceeding years 2013 and 2012 following chronologically. Dotted blue line indicates 1981-2010 average. Top three surface melt years in the record are 2012, 2010 and 2007, respectively. Image source: NSIDC.)

Overall, 2014 showed four melt spikes above 35% melt coverage with three spikes nearing the 40% melt extent coverage mark. By contrast, 2013 only showed two such melt spikes, though the later spike was slightly more intense than those seen during 2014. 2012’s 150 year melt, on the other hand, showed melt extents ranging above 40 percent from mid June to early August with two spikes above 60% and one spike above 80%.

Losses of mass at the surface also showed above average melt trends, but with net melt still below both 2013 and 2012:

Greenland Surface Mass Balance 2014

(Greenland surface mass balance trend for 2014 [blue line] compared to mean for 1990 to 2011 [gray line] and record melt year of 2012 [red line]. Image source: DMI.)

2012 was a strong record year and, on average, we’d expect to see the record jump back to lower levels after such a severe event. However, there’s little to indicate that either 2013 or 2014 have bucked the trend of ongoing and increasing surface melt over Greenland. To the contrary, that trend is now well established with yearly surface mass losses now taking place during all but one of the last 13 years. And there is every indication that 2014 will be a continuation of this trend.

Basal, Interior Melt Not Taken Into Account in the Surface Measure

While surface measures are a good measure of melt on the top of the ice sheet, it doesn’t give much of an idea of what’s happening below the first few feet. There, during recent years, sub surface melt lakes have been forming even as warming ocean waters have eaten away at the ice sheet’s base. And since more than 90% of human-caused warming ends up in the world’s oceans even as many of Greenland’s glaciers plunge hundreds of feet into these warming waters, one might expect an additional significant melt to be coming from the ocean-contacting ice faces.

We can see an indication of the severe combined impact of basal, interior and surface melt in the GRACE mass measurements of the Greenland Ice Sheet since 2002. A record that finds a precipitous and increasing rate of decline:

Greenland Cumulative Mass Loss Through Late 2013

(Greenland cumulative mass loss through mid 2013. Data provided by the GRACE satellite gravity sensor. Image source: NOAA.)

It is this ongoing overall mass loss that tells the ice sheet’s full tale. One that now includes an ever-increasing number of destabilized glaciers speeding more and more rapidly seaward.

Links:

LANCE-MODIS

NSIDC

DMI

NOAA

Nature: Human Warming Now Pushing Entire Greenland Ice Sheet Into the Ocean

Dark Snow

The Arctic Methane Monster Exhales

Large Methane Plumes Discovered on Laptev Continental Slope Boundary

 

 

 

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