Beneath the Cracking, Melting Ice, the Arctic Methane Monster Continues its Ominous Rumbling
(Large Northern Hemisphere methane overburden points to major Arctic emission. Image source: NASA)
“How am I going to be an optimist about this?” — excerpt from Pompey
* * * * *
In the high north, deep beneath the sea ice, sequestered within the sea bed, sleeps a monster. A massive store of methane that is the relic of ages past. A beast whose vast body is composed of hundreds of gigatons of this climatologically volatile gas.
Since times immemorial, the monster slumbered. Accumulating vast size and girth through a near constant rain and sequestration of biological material as the long ages passed. Until human time, that is, when an unprecedented warming began to prod the monster to waking. And so, during recent years, the monster has stirred, even as more and more of this gas has been observed escaping into the atmosphere.
What is happening can be compared to the, at this time, slow initial rumblings of a climate volcano. The gas, forced out of its icy traps in the sea bed, escapes into the ocean where it destabilizes the sea bed and wrecks jarring changes on the marine environment. It bubbles up beneath the ice, running along beneath the strong ice to find holes where the ice is weak, or escaping out from under the ice edge. And in these places, it runs out into the atmosphere. There, the gas is between 20 and 100 times as potent a warming agent as CO2 by volume. There, it inevitably adds to the human warming and emissions nightmare now underway.
In other places the tundra thaws, unleashing its own monstrous volumes of methane, adding to the giant emerging from the troubled seas.
We have seen the large and growing escape of methane in the great 1 kilometer plumes in the East Siberian Arctic Shelf and in other large releases off of Svalbard. We have seen them in the 150 kilometer atmospheric plumes observed by NASA’s CARVE study. We have seen them in ‘hot’ melt lakes that bubble with methane dense enough to burn. We have seen them in the explosive Arctic fires that burn the thawing and volatile land itself.
These all-too-obvious hints of steadily increasing emissions are ominous, not only for their current warming contribution, but for the potential of an even more rapid and violent release. For the eruption of the methane monster, though somewhat gradual now, could, in the build-up to an immense disaster rarely witnessed on Earth, evolve into an ever more deadly and rapid release.
There is evidence of such events in the geological past. Events that have left their black fingerprints splattered over most, if not all, of the climate mass extinctions. And there are a handful of leading scientists who are very concerned that such an event may well be in the offing.
The Methane Monster Continues its, For Now Gradual, Emergence
(Image source: Dr. Yurganov)
Unfortunately, 2013-2014 marked the continuation of a dangerous trend where, once again, rates of Arctic methane emission were shown to increase markedly over those seen during previous years. In the above series of enhanced Aqua satellite images, provided by Dr. Leonid Yurganov you can see the steadily increasing volume of atmospheric methane in Arctic regions during a time of typical methane peaks in late January from 2009 to 2013.
A more comprehensive slide-show ensemble displays Arctic methane increases from 2003 through 2012 here. It is is worth noting that top scale values were 1870 ppb in this video series. In the more recent series (images above and below), the scale has been increased to a maximum value of 1920 to account for spiking atmospheric levels. So don’t let the moving goal posts fool you!
Though we are still about two weeks away from the start of 2014 Arctic methane peaks, early data throughout the fall and winter has shown a marked increase in methane values when compared to similar periods last year. The below image, as an example, compares January 1-10 of 2013 with the same period of 2014:
(Image source: Dr. Yurganov and Sam Carana)
These images, also provided by Dr. Yurganov and composed by Sam Carana, show substantial levels of methane increase for the Arctic during early January of 2014 when compared to the same period in 2013. Especially of note was the significant increase in methane concentrations over the Barents Sea where values were consistently higher than 1920 parts per billion.
It is worth mentioning that during 2009, the same region saw methane levels in the range of 1870 parts per billion and that the jump of +50 ppb or more during this interval is roughly consistent with global average increases. What is more concerning, however, is that these maps clearly show this region of the Arctic as a primary methane hot spot, indicating the likelihood of a very large emission seeping out from under the ice and up from the depths of the ocean.
Overall methane spikes in the Arctic were very significant with, according to observations from Methane Tracker, values exceeding extraordinary levels of 2400 parts per billion in local spikes.
NOAA’s ERSL monitor at Barrow also found large local spikes in the range of 1995 parts per billion during late December:
(Image source: NOAA ERSL)
Note that local methane levels at Barrow, Alaska on the Arctic Circle have risen from an average of 1895 ppb during early 2012 to about 1920 ppb by early 2014, an increase of more than 12 parts per billion per year.
Globally, methane levels have also been on the rise. The record at the Mauna Loa Observatory is now closing in on 1840 parts per billion and shows a significant upward curve during the past two year interval. Though not rising as fast as regions close to the large Arctic emissions sources, the Mauna Loa measure shows a jump of about 15 parts per billion over the two year interval from early 2012 to early 2014.
(Image source: NOAA ESRL)
Above we can see the global trend line for methane as measured at the Mauna Loa Observatory. Note that methane increases had slowed during the period of 2001 to 2006. But in 2007, at about the time Arctic sea ice began its rapid retreat, methane levels commenced a rapid rise. Of particular concern is the gradual upturn in the global average methane curve leading into early 2014.
Very High Arctic Temperature Anomalies Coincide With Rising Methane Levels
As methane levels have continued to rise throughout the Arctic, so have winter temperatures. During 2013-2014, abnormal Arctic winter warmth, especially over the Arctic Ocean, the Barents Sea, and the Bering Sea, has played havoc with Northern Hemisphere weather. In early January, a spate of intense Arctic warmth collapsed the polar vortex, shoving a powerful remnant low southward and setting off a 20 year cold snap in the US. The same extreme winter weather pattern that has impacted much of the US also unloaded a fusillade of storms on the coastlines of the British isles, breaking thousand ton rock structures and reshaping seemingly impervious coastlines.
In this case, the added methane release contributes to polar warming amplification and, at this time, is setting in line a series of increasingly violent weather events likely to ramp up over the coming years and decades. In such cases, the methane monster’s contributions to warming cannot be detached from the changing climate as a whole. In fact, it is the kind of amplifying feedback that makes our situation far more dangerous.
(30 day Global Temperature Anomaly from 1981 to 2010 base line. Image source: NOAA)
Note the extreme temperature anomalies over the past 30 days throughout much of the high Arctic with extremes ranging from 2-6 degrees Celsius above the, already warmer than normal, 1981 to 2010 average. This is just the kind of heat, in conjunction with rising greenhouse gasses, that we would expect from an Arctic undergoing dangerous, if not yet catastrophic, change.
Is Optimism Rational?
Given the evidence showing an amplifying methane signal coming from the Arctic, a signal that becomes louder with each passing year, it becomes more difficult to cling to the comfort provided by a number of the more conservative scientists on the issue of methane release (hydrates, compost bomb or other). Though we have not yet seen major releases large enough to push global methane levels higher by 50, 100 or more parts per billion per year (as we would see during an exceptionally catastrophic event), what we have seen is a growing Arctic release that remains a serious cause for concern.
In such an instance, we might be wise to compare the Arctic Methane Monster to a massive volcano. One that continues to rumble even as it releases ever greater volumes of its climatologically volatile and heat-contributing gasses. As anyone living in the neighborhood of a volcano can attest, it’s generally not a good idea to ignore such things. In this case, the monstrous volcano is so large as to make all the Earth its neighborhood. So we should all be paying attention.
No comments:
Post a Comment