UN says global warming pollutant at record high

The UN weather agency says concentrations of the main global warming pollutant in the world's air reached a record high in 2011.

The World Meteorological Organization says the planet averaged 390 parts per million of heat-trapping carbon dioxide in the atmosphere, a rise of 40 per cent from before the Industrial Age when levels were about 275 parts per million.

WMO officials said Tuesday there was a 30 per cent increase in the warming effect on the global climate between 1990 and 2011, mainly due to carbon dioxide from fossil fuel burning.

WMO secretary general Michel Jarraud said the 350 billion metric tons of carbon dioxide added to the atmosphere since 1750 "will remain there for centuries, causing our planet to warm further and impacting on all aspects of life on Earth."