Greenhouse gases rise to record levels in 2011: UN

GENEVA (AFP) - The volume of greenhouse gases causing global warming rose to a new high last year, the UN World Meteorological Organisation said on Tuesday.

"The amount of greenhouse gases in the atmosphere reached a new record high in 2011," the WMO said as it launched its annual Greenhouse Gas Bulletin report, pointing out that the worst warming gases - carbon dioxide, methane and nitrous oxide - had all reached new highs.

Levels of carbon dioxide - the single most important man-made contributor to climate change - rose to 390.9 parts per million in 2011, which is 2.0 ppm higher than in 2010.

That is 140 per cent over the "pre-industrial level" before 1750, WMO said, adding that in the past 260 years about 375 billion tonnes of carbon have been released into the atmosphere as CO2.