ANTARTICA: The level of carbon-dioxide (CO2) in the atmosphere today is higher than at any time in the past 650,000 years, according to a study published recently in the journal Science.
By drilling into a deep ice core in east Antarctica and analysing the content of air bubbles trapped when the ice was formed, a group of European researchers has been able to chart the level of CO2 in the atmosphere more than 200,000 years further back than previous studies.
Their research shows that the level of CO2, a gas which is linked to global warming, is rising 200 times as fast as at any time during the past 650,000 years.
"It's the rate of increase that's alarming," one of the paper's lead authors, Prof Thomas Stocker, said yesterday.
"These are tremendous changes in the climate system."
Prof Stocker, professor of climate and environmental physics at the University of Bern in Switzerland, said the findings would provide a new baseline for computer climate models.
This would allow scientists to make more accurate predictions about the Earth's changing atmosphere and climate.
He said that through activities such as deforestation and the burning of fossil fuels humans were releasing CO2 "never seen in the atmosphere in millions and millions of years".
This, he said, helped to account for the sudden climate shift. - (La Times-Washington Post service)