The Permian extinction and climate change

Wednesday, December 10th, 2008

We had a programme on TV on Monday: it was called 'Catastrophe' and rightly so. It told the story of the most disastrous event ever for life on Earth. They reckon that 95% of all life (or was it species?) was killed off in this event. This occurred 250 million years ago and signalled the end of the Permian age, an age in which life on Earth and in the oceans really got a move on. I bought a book on this in Baltimore, back in 2004 and the author was in much of the programme.

Theories on how this happened abounded for years but the interesting thing is that it did not happen overnight but rather over 100,000 years. So bang (sorry!) goes the asteroid impact theory. The theory of choice has it all starting with an unbelievable volcanic eruption in Siberia and there is plenty of evidence for that. Carbon and sulphur dioxides + the usual dust were spewed into the atmosphere creating global warming but the temp rise was 'only' about 5 degrees C. Now that would knock off quite a few, many of us included if we'd been around, but it was not enough to do for 95%.

Enter methyl hydrate or methyl clathrate as it is also called. Interesting compound - typically one molecule of methane gets trapped in a sort of lattice of water molecules. The methane comes from decaying bacteria and the water captures it and freezes. And there are said to be zillions on tons of it trapped on the ocean floor. The problem with this stuff is that right now, just as in the Permian, it is quite close to its decomposition point. And when it decomposes, it goes off with a bang releasing all its methane as a giant bubble. It is suspected that such events occur occasionally today and may account for the strange disappearance of the odd supertanker.

Back to the Permian. Well the CO2 lifted the average global temp by 5C and slowly, it is believed, that the oceans (which have a higher thermal inertia) warmed up too. And then bang, the methyl hydrates came apart releasing their methane which, the programme said, is 25 times worse as global warming gas than CO2. So that's what did for much of the rest of life on Earth at the time.

Very plausible I thought.

Is this relevant to today, I wondered. Can't be sure. I do note however that the Japanese are looking to source methane from these hydrates but the problem is that they do not release their methane slowly so how are they gonna capture it?

I suppose the message is that we might just cope with CO2 induced global warming. Sure millions might die of consequence but I'd be OK cus my house is about 325 feet above mean sea level. Maybe I might even grow bananas and pineapples in the garden and it would be nice to have the car frost free all year round. But if the methane cometh, we'd all be up 'shit street.'