Date:14/05/2008 URL: http://www.thehindu.com/2008/05/14/stories/2008051455831100.htm

Opinion - News Analysis

World CO₂ levels highest for 650,000 years

David Adam

The concentration of carbon dioxide in the atmosphere has reached a record high, according to the latest figures, renewing fears that climate change could begin to slide out of control.

Scientists at the Mauna Loa observatory in Hawaii say that CO₂ levels in the atmosphere now stand at 387 parts per million (ppm), up almost 40 per cent since the industrial revolution and the highest for at least the last 650,000 years.

The figures, published by the U.S. National Oceanic and Atmospheric Administration on its website, also confirm that carbon dioxide, the chief greenhouse gas, is accumulating in the atmosphere faster than expected. The annual mean growth rate for 2007 was 2.14 ppm — the fourth year in the last six to see an annual rise greater than 2 ppm. From 1970 to 2000, the concentration rose by about 1.5 ppm each year, but since 2000 the annual rise has leapt to an average 2.1 ppm.