Saturday 2 August 2014

Fast-moving events on the climate front

Permafrost Fires Advancing Toward Arctic Ocean Shores

Smoke from Siberian Tundra Fires August 1, 2014
(Smoke from Siberian permafrost fires entrained in wind pattern blowing over the East Siberian and Laptev seas. What can best be described as a synoptic pattern of smoke stretching for more than 2000 miles. For reference, we are looking at the heart of Siberia, the bottom edge of frame touches the Arctic Ocean. Total width of frame is more than 2000 miles. Image source: LANCE-MODIS.)
1 August, 2014
From the Northwest Territory of Canada to a broad central section of Russian Siberia called Yedoma, the permafrost fires this year have been vicious, powerful and colossal. They have burned deep into the basement soil and permafrost layer, casting out billows of dense, smokey material that, at times, has blanketed a majority of both Siberia and the North American Continent.
In Minnesota, hundreds of miles away from the still raging Northwest Territory fires, James Cole, who comments here frequently, noted:
Forest fire smoke here in N.E. Minnesota was off the charts yesterday! I went out to watch the blazing red sun sink below the green hills. This almost invisible red ball brought back an old memory from watching a sun set in San Diego County during a very bad fire out break back when I was home ported with my ship there. These Alberta fires are a huge distance from here, but I can guess at their size by the thick gray haze, the smell and a sunset just like one in an active fire zone.
And these fires aren’t anything normal. They burn the land as well as the trees. They cast off an inordinately high volume of smoke, such that they are far more visible in the satellite shot than more southerly fires of similar size. And they continue to burn for weeks and weeks — with lands that were lit nearly a month ago still casting off smoke and fire from the same locations.
The quantity of material necessary to keep such fires burning from the same location day in, day out, must be immense and it is becoming increasingly obvious to this observer that woodland as well as the soil and, likely, the thawing permafrost itself have become involved. It is a basement layer that, when fully thawed can be scores of feet deep. A set of peat-like material that, were it to be sequestered, would likely turn into a hundreds foot deep seam of coal over ages of heat and pressure. Instead, it is now being liberated as fuel for fires by human-caused warming.
Wildfire burning near Laptev Sea August 1, 2014(Wildfire burning near Laptev Sea on August 1, 2014. The terrain in this region is tundra and tundra lakes, similar to the Yamal region where methane outburst sites where recently discovered. Wildfire is the comet like feature in upper center frame. The shoreline of the Laptev is visible along the lower frame border. Note the steely gray pallor of smoke running south to north [top to bottom] through the image frame. For reference, bottom edge of frame is about 150 miles, fire front is approximately three miles. Image source:LANCE-MODIS.)

On the Canadian side, the fires have primarily remained in the same region, simply continuing to burn from mostly the same sources or spreading only to local areas. But on the Russian side, the fires have leapt from their original cauldrons to ignite in massive blazes along regions both east and west, north and south.
Over recent days, fires have been creeping northward along a ridge line toward the Laptev Sea. Yesterday, a large fire ignited in the treeless tundra just 70 miles south of Arctic Ocean waters. You can see a close up image of this fire in the MODIS shot above.
So we have hard tundra burning just 70 miles south of the Arctic Ocean. No trees here, just an endless expanse of thawing ground.
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Hat tip to Colorado Bob (First Observation)
Hat tip to James Cole

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.)
1 August, 2014
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 to 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.

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The Really Scary Thing About Those Jaw-Dropping Siberian Craters


1 August, 2014

Russian scientists have determined that a massive crater discovered in a remote part of Siberia was probably caused by thawing permafrost. The crater is in the Yamal Peninsula, which means “end of the world.” It caught hold of the media spotlight in mid-July when it was spotted by oil and gas workers flying over the area. At roughly 200 feet wide and seemingly bottomless, speculation abounded about the cause with the Siberian Times reporting that, “theories range from meteorites, stray missiles, a man-made prank, and aliens, to an explosive cocktail of methane or shale gas suddenly exploding.”

Since this first discovery, two other smaller craters have been spotted in the surrounding regions, fueling even more armchair conjecture. Russian scientists sent to the site are now providing first-hand data showing that unusually high concentrations of methane of up to 9.6 percent were present at the bottom of the first large crater shortly after it was discovered on July 16. Andrei Plekhanov, an archaeologist at the Scientific Centre of Arctic Studies in Salekhard, Russia, who led an expedition to the crater, told The Journal Nature that air normally contains just 0.000179 percent methane.

The last two summers in the Yamal have been exceptionally warm at about nine degrees Fahrenheit above average.

According to Plekhanov, the last two summers in the Yamal have been exceptionally warm at about nine degrees Fahrenheit above average. Rising temperatures could have allowed the permafrost to thaw and collapse, releasing the methane previously trapped by the subterranean ice. Methane is the primary component of natural gas. The original crater is about 20 miles from a large natural gas plant and the entire Yamal Peninsula is rich in natural gas that is being extensively tapped to help fuel Russia’s natural gas boom.

Hans-Wolfgang Hubberten, a geochemist at the Alfred Wegener Institute in Potsdam, Germany, told Nature that climate change and the slow, steady thaw of the region could be to blame.

Gas pressure increased until it was high enough to push away the overlying layers in a powerful injection, forming the crater,” he said.

This frame grab made Wednesday, July 16 shows the 200-foot wide crater discovered in the Yamal Peninsula. CREDIT: ASSOCIATED PRESS TELEVISION


While staring down into the abyss of these craters is a scary thought, the release of large quantities of greenhouse gases from melting permafrost is existentially daunting. A study from earlier this year found that melting permafrost soil, which typically remains frozen all year, is thawing and decomposing at an accelerating rate. This is releasing more methane into the atmosphere, causing the greenhouse effect to increase global temperatures and creating a positive feedback loop in which more permafrost melts.


The world is getting warmer, and the additional release of gas would only add to our problems,” said Jeff Chanton, the John Widmer Winchester Professor of Oceanography at Florida State and researcher on the study. According to Chanton, if the permafrost completely melts, there would be five times the current amount of carbon equivalent in the atmosphere.


Kevin Schaefer, a permafrost scientist at the National Snow and Ice Data Center, told ThinkProgress that there are actually two sources of GHGs released by melting permafrost: methane hydrates that destabilize when permafrost temperatures rise, as has been the case in Siberia, and frozen organic matter.


Note that the methane hydrate and the decaying organic matter emissions result from two completely different mechanisms,” said Schaefer. “Methane hydrate emissions come from deep permafrost due to purely physical processes. The decaying organic matter emissions come from near-surface permafrost due to purely biological processes.”


He said that as the permafrost thaws, the organic matter will also thaw and begin to decay, releasing CO2 and methane into the atmosphere. “Published estimates indicate 120 gigatons of carbon emissions from thawing permafrost by 2100, which would increase global temperatures by an additional 7.98 percent,” he said.
As with other processes in the permafrost zone, abrupt changes appear to be as or perhaps more important than slow gradual change.


Schaefer said the phenomenon of the Siberian craters was a surprise to him because he thought the methane would leak out more slowly. Capturing these large bursts of methane before they enter the atmosphere could be possible, according to Schaefer, however extremely difficult.


The key is drilling into the permafrost before the methane escapes,” he said. “However, creating the infrastructure just to get to these remote locations is daunting.”


He said that capturing the emissions from decaying organic matter would be impossible.

Ted Schuur, a professor of ecosystem ecology at the University of Florida and leader of the Permafrost Carbon Network, told ThinkProgress that the Siberian craters remind him of ‘hot spots’ of methane bubbling that occur both in lakes and undersea in the permafrost zone.


This could be a terrestrial version that was previously capped by ground ice in permafrost,” he said. “If indeed they are the result of warming permafrost they could be a significant pathway of greenhouse gas release to the atmosphere. As with other processes in the permafrost zone, abrupt changes appear to be as or perhaps more important than slow gradual change.”


A survey of 41 permafrost scientists in 2011 estimated that if human fossil-fuel use remained on a high projection and the planet warmed significantly, gases from permafrost could eventually equal 35 percent of present day annual emissions. In the few years since then, emissions have continued to rise. If emissions are heavily curtailed, greenhouse gases from permafrost could make up as little as around the equivalent of 10 percent of today’s human-caused emissions. This is far lower, but still highly disconcerting.


Even if it’s 5 or 10 percent of today’s emissions, it’s exceptionally worrying, and 30 percent is humongous,” Josep G. Canadell, a scientist in Australia who runs a global program to monitor greenhouse gases, told the New York Times at the time of the study. “It will be a chronic source of emissions that will last hundreds of years.”

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