January 22nd, 2005

It was climate change that wiped out most life 251m years ago

A report in last weeks "Science" online journal ties the "Great Dying", the worlds largest single mass extinction 251m years ago which almost made the Earth a dead and lifeless planet, to volcano-induced climate change.

The large amount of carbon and sulphur ejected into the air, and sulphur running into the sea killing ocean floor based life, seemed to have warmed the earth fatally and suffocated life through lack of oxygen.

"They suspect that as this continuing volcanism warmed the planet, large stores of methane gas locked in the ocean floor, triggering runaway greenhouse warming.

Scientists estimate that by the end of the 15 million-year period, 90 percent of all marine life and 75 percent of terrestrial species were extinct."

There has been debate over the cause, the previous main suspect being an asteroid collision similar to which probably wiped out the dinosaurs 65-million years ago, however Peter Ward who headed one of the two studies which had scientists from four continents participating, states categorically that climate change was most likely responsible:

"The geologic data are consistent with a more protracted catastrophic ecosystem collapse than a sudden impact would produce," he says. "If an impact occurred at all, it had a minor role."

'Ward's conclusions are supported by another team of scientists, who have been studying ocean sediments off the coasts of Australia and China, where they found evidence of extremely low oxygen levels in the upper ocean.'

"I think temperatures rose to a critical point. It got hotter and hotter until it reached a critical point and everything died," Ward said. "It was a double-whammy of warmer temperatures and low oxygen, and most life couldn't deal with it."

This has made a lot of the world's press: [Associated Press (AP)] [French Press Agency (AFP)] [The Australian] [Seattle PI] [Independent]

If you want to read something truly spine chilling however, here is a comment piece (quoted below) from 18-months ago by George Monbiot in the Guardian about this era. Although there are some differences between the sudden climate change we're initiating and that initiated by volcanic activity, the similarities significantly outweigh them:

"So how much warming took place? A sharp change in the ratio of the isotopes of oxygen permits us to reply with some precision: 6C. Benton does not make the obvious point, but another author, the climate change specialist Mark Lynas, does. Six degrees is the upper estimate produced by the UN's scientific body, the intergovernmental panel on climate change (IPCC), for global warming by 2100. A conference of some of the world's leading atmospheric scientists in Berlin last month concluded that the IPCC's model may have underestimated the problem: the upper limit, they now suggest, should range between 7 and 10 degrees. Neither model takes into account the possibility of a partial melting of the methane hydrate still present in vast quantities around the fringes of the polar seas."

"Suddenly, the events of a quarter of a billion years ago begin to look very topical indeed. One of the possible endings of the human story has already been told. Our principal political effort must now be to ensure that it does not become set in stone."

Kyoto Protocol March and "Climate Crisis" meetings in the UK

On Saturday 12th February there will be a march through London commencing the start of the Kyoto Protocol, and also in protest at the US's refusal to sign up. In the run up there will be "Climate Crisis" meetings organised by several different political groups across the country to "assess the scale & nature of the Climate threat, politics of Climate change, how to fight the Bush administration on climate, building a movement to press for urgent action". The dates of these are as follows:

Cardiff - Tuesday, 25th January, 7.00 pm
Oxford - Wednesday, 26th January, 7.30 pm
Brighton - Thursday, 27th January, 6.00 pm
Manchester - Thursday, 27th January, 7.00 pm

Bristol - Monday, 31st January, 7.30 pm
Norwich - Tuesday 1st February, 7.30 pm
Southampton - Wednesday 2nd February, 7.00 pm
London - Thursday, 3rd February, 7.00 pm
Birmingham - Thursday, 3rd February, 7.30 pm
Liverpool - Friday, February 4th, Time TBA

For further details and exact location details of these meetings, see here. See the main pages of the following groups for more information on the Kyoto Protocol March in London: Campaign Against Climate Change and Rising Tide.