Tuesday, 20 October 2009

Methane – it’s a gas

Methane is a far more powerful greenhouse gas than CO2, although it stays active in the atmosphere for less time. Unlike carbon dioxide, which can remain in the atmosphere a century or more once released, methane persists in the air for about 10 years.  It will be a serious problem if the permafrost in the tundra and Alaska melts and the underground methane comes up and the previously frozen vegetation generates more. It would be even worse if the undersea methane clathrates bubbled up (a form of methane+water ice which stays down there because of the cool temperature and pressure). Large scale release of methane would be a very strong positive feedback to global warming and if it starts to happen, then we are *%$#*’ed.

Large scale release of methane from clathrates has been associated with very rapid temperature rises and mass extinctions of species in the pre-historic past  - Permian-Triassic extinction event and the Paleocene-Eocene Thermal Maximum

The story linked to below shows that it is not just “natural” releases that deserve attention because apparently there are large scale leaks from the global oil and gas processing infrastructure that have the same warming power of the emissions from over half of the coal plants in the United States. Because of methane’s lower residence time in the atmosphere, aggressively reining in emissions now would mean that far less of the gas would be warming the earth in a decade or so. Fixing the leaks would be a valuable “low hanging fruit” to get on with NOW!

click on this link to the New York Times story


This picture uses an Infra-red camera to show an “invisible” leak form a gas holder

In routine operations, great yet invisible plumes of gas enter the atmosphere when new wells are activated, old wells are invigorated to boost gas flows and wells are purged of fluids by letting out cough-like bursts of gas.


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