Tuesday, 14 May 2013

Methane levels in Antarctica

What an odd headline!  Who is to say that Antarctic methane has peaked - I personally doubt it!

Antarctic methane peaks at 2249 ppb



Methane Hydrates,
10 May, 1023

Methane levels in the atmosphere above Antarctica peaked at 2249 parts per billion today. The chart below shows that very high levels of methane have been recorded over Antarctica for some time now.



These very high methane emissions occur on the heights of East Antarctica. The map below shows the highest altitudes on Antarctica colored red.

Antarctic map by the U.K.-based Centre for Polar Observation & Modelling (CPOM)


Antarctica is covered in a thick layer of ice, as indicated by the image below. It appears that these very high emissions are caused by methane from hydrates that is escaping in the form of free gas bubbling up through the ice sheet.
Antarctic map showing the height of the ice sheet created with CryoSat-2 data
The danger is that such emissions will escalate, not only over Antarctica, but also on the Qinghai-Tibet Plateau and in the Arctic.

Peter Carter, contributor to the Arctic-news blog, comments as follows:

“This is of enormous planetary emergency significance because unlike the Arctic methane hydrate is the only possible source of this extraordinary emission of Antarctic methane.”

Albert Kallio, also contributor to the Arctic-news blog, comments as follows:

“The Antarctic methane rise is an extremely worrying phenomenon. It can be caused by two processes. Neither a direct sunlight, nor atmospheric warming, can reach to the base of the ice sheet. However, it is still almost certainly to be a result of global warming – teleconnections – like other recent methane rises seen over the Arctic Ocean, Siberia and North American tundra:

(1) Theoretically, it could be a result of melt water percolation through Antarctic ice sheet to its base, and then, thawing the permafrost soil beneath the ice sheet.

(2) I suggest that methane is coming out from the Antarctic soils because of isostatic equilibrium change that has occurred between the weight loads levied by the East Antarctic Ice Sheet (EAIS) and that of the West Antarctic Ice Sheet (WAIS).

While the East Antarctic ice accumulates weight, the West Antarctic ice loses its weight due to ablation (melting). As the fluids both in the asthenosphere and the crust are incompressible, the changing fluid pressure of one channels from one to the other via the subterranean fluid conduits. These can consist both hot magma and water which transports heat from deep towards the surface.

Asthenosphere is made of extremely water-soluble, but dense rock, Peridotite. If incursion of water from above gets into the peridotite, it hydrates and starts to melt. Hydrogen in water molecule tears molecules like NaCl apart to Na+ and Cl- as the bouncing water molecule swipes its two hydrogen tails in collisions with the other molecules. While NaCl is completely knocked down by water molecule’s hydrogen, in case of Peridotite molecules only some atomic parts are blown out, hence the process is called “partial melting”.

The First Nations UN General Assembly motion’s geophysical annotations attribute the onset of the Ice Ages completely for the continental plates drifting phenomenon. The continental plate drifting had caused crustal shearing at very high latitudes. The newly formed faults and the shearing of the continental plate then allowed water to reach Peridotite to liquefy it. This caused large lava floods onto sea floor boiling the ocean's water which then landed as snow.

My view is that Antarctica has developed now an adequate disequilibrium which pumps water into Peridotite, which then liquefies in the asthenosphere (and also in the crustal plate where there are Peridotite pockets within the Antarctic plate).

As a result of the ice sheet disequilibrium, some ice and water has forced their way into the Peridotite reservoirs, now liquefying it. This liquefaction allows heat to escape in the forms of heated water (a creation of subglacial geysers), or rock incursions such as lava floods and subglacial volcanoes that have started to develop beneath the Antarctic Ice Sheet. The Gamburtsev Range is probably this kind of series of volcanoes and is a candidate for the EAIS methane.

As the heat starts rising more to the surface to (the base of the East Antarctic Ice Sheet), the ground warms and releases methane which is then dissolved into subglacial Antarctic water currents. (There are plenty of subglacial water currents and lakes to transport methane and dissolve it in water beneath Antarctic ice.)

The accumulation of water, pre-existing faults in bed rocks under the Antarctic ice sheet and local weight loads all determining where and when the methane starts oozing out once the ice sheet has now sufficiently changed from its multi-millennial equilibrium.”.....

For rest of article GO HERE



1250 - New group calls for action on methane


A new group, named 1250, calls for governments around the world to take action on methane.

Just like 350 parts per million has become a popular target for carbon dioxide, the group similarly advocates a target for methane, aiming for a reduction of methane to 1250 parts per billion.

"Methane is far more potent than carbon dioxide as a greenhouse gas, making it important to reduce levels of methane in the atmosphere," explains founder Nathan Currier; "1250 is not just an advocacy group for methane cuts, however. Rather, it is a group focusing on near-term climate as a whole, and on practical pathways to constructing a ‘climate bridge’ towards a stable and sustainable future."

These very high methane emissions occur on the heights of East Antarctica. Antarctica is covered in a thick layer of ice. It appears that these very high emissions are caused by methane from hydrates that is escaping in the form of free gas bubbling up through the ice sheet.

The danger is that such emissions will escalate, not only over Antarctica, but also on the Qinghai-Tibet Plateau and in the Arctic

The group has a website at http://1250now.org/ and encourages people to join its mailing list




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