A catastrophe of unimaginable propertions is unfolding in the Arctic
Ocean. Huge quantities of methane are erupting from the seafloor of the
East Siberian Sea and entering the atmosphere over the Arctic Ocean.
As the top image above shows, peak levels as high as 2363 ppb were
recorded at an altitude of 19,820 ft (6041 m) on the morning of August
12, 2014. The middle image shows that huge quantities of methane
continued to be present over the East Siberian Sea that afternoon, while
the bottom image shows that methane levels as high as 2441 ppb were
recorded a few days earlier, further indicating that the methane did
indeed originate from the seafloor of the East Siberian Sea.
On August 12, 2014, peak methane levels at higher altitudes were even
higher than the readings mentioned on above image. Levels as high as
2367 ppb were reached at an altitude of 36,850 ft (11,232 m). Such high
levels have become possible as the huge quantities of methane that were
released from the seafloor of the Arctic Ocean over the period from
October 2013 to March 2014, have meanwhile descended to lower latitudes
where they show up at higher altitudes.
Methane eruptions from the Arctic Ocean's seafloor helped push up mean
global methane levels to readings as high as 1832 ppb on August 12,
2014.
Ironically, the methane started to erupt just as an international team
of scientists from Sweden, Russia and the U.S. (SWERUS-C3), visiting the
Arctic Ocean to measure methane, had
ended their research.
Örjan Gustafsson
describes part of their work: “Using
the mid-water sonar, we mapped out an area of several kilometers where
bubbles were filling the water column from depths of 200 to 500 m.
During the preceding 48 h we have performed station work in two areas on
the shallow shelf with depths of 60-70m where we discovered over 100
new methane seep sites.”
Örjan Gustafsson adds that “a tongue of relatively warm Atlantic water,
with a core at depths of 200–600 m may have warmed up some in recent
years. As this Atlantic water, the last remnants of the Gulf Stream,
propagates eastward along the upper slope of the East Siberian margin,
our SWERUS-C3 program is hypothesizing that this heating may lead to
destabilization of upper portion of the slope methane hydrates.”
 |
Schematics of key components of the Arctic climate-cryosphere-carbon system that are addressed by the SWE-C3 Program. a,b) Sonar images of gas plumes in the water column caused by sea floor venting of methane ( a: slope west of Svalbard, Westbrook et al., 2009; b: ESAO, Shakhova et al., 2010, Science). c) Coastal erosion of organic-rich Yedoma permafrost, Muostoh Island, SE Laptev Sea. d) multibeam image showing pockmarks from gas venting off the East Siberian shelf. e) distribution of Yedoma permafrost in NE Siberia. f) Atmospheric venting of CH 4, CO 2. ( SWERUS-C3) |
Örjan Gustafsson further adds that SWERUS-C3
researchers have on earlier expeditions documented extensive venting of
methane from the subsea system to the atmosphere over the East Siberian
Arctic Shelf.
In 2010, team members Natalia Shakhova and Igor Semiletov
estimated the accumulated methane potential for the Eastern Siberian Arctic Shelf alone to be as follows:
- organic carbon in permafrost of about 500 Gt;
- about 1000 Gt in hydrate deposits; and
- about 700 Gt in free gas beneath the gas hydrate stability zone.
Back in 2008, Shakhova et al.
wrote a paper warning
that “we consider release of up to 50 Gt of predicted amount of hydrate
storage as highly possible for abrupt release at any time.”
Last year, a team of researchers including Professor Peter Wadhams
calculated that such a 50 Gt release would cause global damage with a price-tag of $60 trillion.
As Prof Wadhams explains in the
video below: “We really have no choice except to seriously consider the use of geoengineering.”
Sea
surface temperatures as high as 18.8°C are now recorded at locations
where warm water from the Pacific Ocean is threatening to invade the
Arctic Ocean.
At the same time, huge amounts of very warm water are carried into the
Arctic Ocean by the Gulf Stream through the North Atlantic. The image
below illustrates how the Gulf Stream brings very warm water to the edge
of the sea ice.
Waters close to Svalbard reached temperatures as high as 62°F (16.4°C)
on July 29, 2014 (green circle). Note that the image below shows sea
surface temperatures only. At greater depths (say about 300 m), the Gulf
Stream is pushing even warmer water through the Greenland Sea than
temperatures at the sea surface.
Since the passage west of Svalbard is rather shallow, a lot of this very
warm water comes to the surface at that spot, resulting in an anomaly
of 11.1°C. The high sea surface temperatures west of Svalbard thus show
that the Gulf Stream can carry very warm water (warmer than 16°C) at
greater depths and is pushing this underneath the sea ice north of
Svalbard. Similarly, warm water from greater depth comes to the surface
where the Gulf Stream pushes it against the west coast of
Novaya Zemlya.
As Malcolm Light writes in an
earlier post:
The West Spitzbergen Current dives under the Arctic ice pack west of
Svalbard, continuing as the Yermak Branch (YB on map) into the Nansen
Basin, while the Norwegian Current runs along the southern continental
shelf of the Arctic Ocean, its hottest core zone at 300 metres depth
destabilizing the methane hydrates en route to where the Eurasian Basin
meets the Laptev Sea, a region of extreme methane hydrate
destabilization and methane emissions.
The images below give an impression of the amount of heat transported into the Arctic Ocean.
The image below gives an idea how methane eruptions from the
seafloor of the Arctic Ocean could unfold over the coming decades. For
more on this image, see
this post and
this page.
As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog at
climateplan.blogspot.com and as illustrated by the image below.
