Greenhouse gases rise to record high in 2010: UN
The amount of global warming-causing greenhouse gases in the atmosphere rose to a new high in 2010, and the rate of increase has accelerated, the UN weather agency said on Monday.
Levels of carbon dioxide -- a greenhouse gas and major contributor to climate change -- rose by 2.3 parts per million between 2009 and 2010, higher than the average for the past decade of 2.0 parts per million, a new report by the World Meteorological Organisation found.
"The atmospheric burden of greenhouse gases due to human activities has yet again reached record levels since pre-industrial time," said WMO Secretary-General Michel Jarraud.
Greenhouse gases trap radiation within the earths atmosphere, causing it to warm.
Scientists attributed the rise in carbon dioxide, which contributes about 64 percent to climate warming, to fossil fuel burning, deforestation and changes in land-use.
Methane, produced by cattle-rearing and landfills, is the second most important greenhouse gas after carbon dioxide followed by nitrous oxide.
The WMO's annual Greenhouse Gas Bulletin said methane levels had risen after a period of relative stabilisation from 1999 to 2006, possibly due to the thawing of the Northern permafrost and increased emissions from tropical wetlands.
Nitrous oxide, emitted into the atmosphere from natural and man-made sources, including biomass burning and fertilizer use, was 323.2 parts per billion in 2010 -- 20 percent higher than in the pre-industrial era, defined as the period before 1750.
"Its impact on climate, over a 100 year period, is 298 times greater than equal emissions of carbon dioxide," said the report.
"It also plays an important role in the destruction of the stratospheric ozone layer which protects us from the harmful ultraviolet rays of the sun."
"Even if we managed to halt our greenhouse gas emissions today -- and this is far from the case -- they would continue to linger in the atmosphere for decades to come and so continue to affect the delicate balance of our living planet and our climate," said Jarraud.
"Now more than ever before, we need to understand the complex, and sometimes unexpected, interactions between greenhouse gases in the atmosphere, Earths biosphere and oceans."
The seventh Greenhouse Gas Bulletin comes ahead of a new round of UN climate talks in South Africa next Monday, testing global resolve to tackle what scientists warn is a time bomb with an ever-shorter fuse.
Analysts say the UN process is still traumatised by the near-collapse of the 2009 Copenhagen Summit and, in Durban, faces a bustup over the Kyoto Protocol, the only agreement setting legal curbs on greenhouse gases.
© 2011 AFP