Minggu, 09 Agustus 2015

The Methane Monster


At no time in the past did humans exist under conditions that we are facing now, no matter how far back you go in history.

Global mean methane levels as high as 1840 parts per billion were recorded on August 4, 2015. This is the highest mean level since records began and this new record is likely to be superseded by even higher levels soon.

The carbon dioxide that is released now will only reach its peak impact a decade from now. Methane's high immediate impact makes it more important than carbon dioxide emissions in driving the rate of global warming over the coming decade.

The Pacific Ocean is very warm at the moment. Warm water flows from the Pacific Ocean through the Bering Strait into the Arctic Ocean. Sea surface temperatures in the Bering Strait were as high as 20.5°C (or 69.1°F) on August 4, 2015. That is 8.7°C (or 15.6°F) warmer than the water used to be. Sea surface temperatures as high as 11.8°C (53.2°F) were recorded in between Greenland and Svalbard on August 7, 2015, an anomaly of 8.5°C (15.3°F).

[ click on image to enlarge ]
The danger is that further warming will cause collapse of the sea ice, which in turn will lead to even more rapid warming of the Arctic Ocean, while the presence of more open water will also increase the opportunity for powerful storms to develop that can mix high sea surface temperatures all the way down to the seafloor, resulting in destabilization of sediments and triggering releases of methane that can be contained in such sediments in huge amounts.

Methane releases from the seafloor of the Arctic ocean threaten to cause rapid local warming that in turn will trigger further methane releases, in a vicious cycle of runway warming that could destroy habitat for humans within decades.

[ click on image to enlarge ]
The situation is dire and calls for comprehensive and effective action as discussed at the Climate Plan at the Arctic-News Blog.


References

-  Sea surface temperatures in the Bering Strait on August 4, 2015. 

- Sea surface temperatures in between Greenland and Svalbard on August 7, 2015.
http://earth.nullschool.net/#2015/08/07/0000Z/ocean/surface/currents/overlay=sea_surface_temp_anomaly/orthographic=18.75,79.02,3000

- Maximum warming occurs about one decade after a carbon dioxide emission, by Katharine L Ricke and Ken Caldeira (2014)
http://iopscience.iop.org/1748-9326/9/12/124002/article

- Methane's Global Warming Potential
http://arctic-news.blogspot.com/p/faq.html#13



THE METHANE MONSTER - by Sam Carana At no time in the past did humans exist under conditions that we are facing now,...
Posted by Sam Carana on Sunday, August 9, 2015

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