Wednesday, May 28, 2008

Beware the Methane Clathrates!!!

Large methane release could cause abrupt climate change as happened 635 million years ago

UCR-led research team says methane-triggered global warming ended last 'snowball' ice age; dramatically reorganized Earth system

An abrupt release of methane, a powerful greenhouse gas, about 635 million years ago from ice sheets that then extended to Earth’s low latitudes caused a dramatic shift in climate, triggering a series of events that resulted in global warming and effectively ended the last “snowball” ice age, a UC Riverside-led study reports.

The researchers posit that the methane was released gradually at first and then in abundance from clathrates – methane ice that forms and stabilizes beneath ice sheets under specific temperatures and pressures. When the ice sheets became unstable, they collapsed, releasing pressure on the clathrates which began to degas.

“Our findings document an abrupt and catastrophic means of global warming that abruptly led from a very cold, seemingly stable climate state to a very warm also stable climate state with no pause in between,” said Martin Kennedy, a professor of geology in the Department of Earth Sciences, who led the research team.


Now it depends on whether or not the Snowball Earth hypothesis is correct or not whether you follow the above. However, methane releases have greatly influenced the past climate. Most horrifyingly, the terminal Permain. However, more recently, the Paleocene-Eocene Thermal Maximum has been attributed to methane releases.

There has been a lot of talk about mining the clathrates for sources of natural gas. While this is interesting in some senses - after all, you are converting very scary greenhouse gas to a lesser one and drain the possibly nasty reserves - there are still dangers. Right now, the efficiency of the recovery causes 90% losses to the atmosphere. erk! Not good. Let's improve that before we start venting that much methane into the atmosphere, please! We have to convince the Koreans of that, since South Korea announced that they are going ahead with mining their off-shore sources. o.O

A bit of a tangential thought. One possible contributing factor to Fermi Paradox would be that many worlds are in their Snowball phase at any given time. It's end may have helped trigger complex life here on Earth. If nothing kicks those worlds out of the Snowball stage, life might take a lot longer to develop into complex forms. If ever. OTOH, if the world's never develop a self regulating system like Earth's ecosystems, then either the Snowball could return, pretty much screwing advanced life or rendering the most complicated ecosystems like our Arctic or Antarctic or it may trip the otherway and turn into a runaway Greenhouse making the world into xenoVenus .

Just some thoughts.

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