Still
more coming out about methane hydrates and global warming.
Are
Methane Hydrates Dissolving?
16
August, 2012
West
of Spitsbergen methane gas is effervescing out of the seabed. Is this
an indication that methane hydrates in
the seabed are dissolving due to rising temperatures? And what would
the effects be? An expedition with the German research vessel MARIA
S. MERIAN and the submersible JAGO lead by GEOMAR | Helmholtz Centre
for Ocean Research Kiel hopes to help answer these questions. The
expedition began this week in Reykjavik.
The
average temperatures of the atmosphere are rising; the average
temperatures of the oceans, too. Not only living organisms react
sensititvely to these changes. The transitional zones between shallow
shelf seas and the deep sea at continental slopes store a huge amount
ofmethane hydrates
in the sea bed.
These
specific, ice-like compounds only forms at low temperatures and under
high pressure. When the water temperature directly above the sea bed
rises, some of the methane hydrates could dissolve and release the
previously bound methane.
"This
scenario incorporates two fears: Firstly that enormous amounts of
this very powerful greenhouse gas will
be released into the atmosphere, and secondly that the continental
slopes may become unstable" explains the geophysicist Professor
Christian Berndt from GEOMAR, Helmholtz Centre for Ocean Research
Kiel.
He
is leading an expedition starting today on the German research vessel
MARIA S. MERIAN which will analyse the sea off the western shore of
Spitsbergen in order to find out whether the first methane hydrates
in the sea bed are dissolving and what the consequences might be.
The
expedition builds on research conducted by marine scientists from
Kiel who worked in this area of the sea in 2008. Back then they found
over 250 places where gas was escaping the sea bed. "These spots
lie directly on the border of the area of stable hydrates"
explains Professor Berndt. "Therefore we presume that the
hydrates are dissolving from the rim inwards."
During
the upcoming expedition, the scientists from Kiel will be working
together with colleagues from Bremen, Switzerland, Great Britain and
Norway to discover whether the gas emanation shows signs of dissolved
hydrates and whether this is due to warmer sea beds.
With
the help of echo sounders, researchers will seek out new gas sources
in order to determine the total amount of escaping gas. With
Germany's only submersible JAGO, they will closely investigate the
gas outlets in up to 400 metres depth.
"It
is interesting for us, for example, to find out whether special
microorganisms that can break down the methane before it is released
in the atmosphere have settled around the outlets" explains
Professor Tina Treude from GEOMAR, who will be running the
microbiological work during the expedition.
Parallel
to this, geophysicists, lead by Professor Sebastian Krastel from
GEOMAR, will investigate the slopes under the gas outlet spots for
signs of instability using acoustic and seismic methods.
"The
methane hydrates act like binding cement on these slopes. If they
dissolve, chances are that parts of the slopes will slide",
explains Professor Krastel, who focuses on marine hazards at GEOMAR.
"Overall
the program on this trip is very extensive. Now let us hope that the
weather will play along so that we can conduct all planned tests",
says the head of the expedition Christian Berndt shortly before the
departure to Iceland.
Crisis at the North Pole
With thanks to Extinction Protocol


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