95% chance that humans are to blame for global warming

A new study has found that there is a 95% chance that human activity is to blame for global warming, and only 5% that the climate change is due to natural factors.

According to a report in The Times, London, the study was carried out by senior scientists from the Met office, Hadley Centre, Edinburgh University, Melbourne University, and Victoria University in Canada.

The "fingerprints" of human influence on the climate can be detected not only in rising temperatures but also in the saltiness of the oceans, rising humidity, changes in rainfall, and the shrinking of the Arctic ice at the rate of 6,00,000 sq km a decade.

There was less than 5% likelihood that natural variations in climate were responsible for the changes, the study said, adding that the Intergovernmental Panel on Climate Change (IPCC) had understated mankind's overall contribution to climate change.

The IPCC had said in 2007 that there was no evidence of warming in Antarctica. But the study said the latest observations showed that man-made emissions were having an impact on even the remotest continent.

The panel assessed more than 100 recent peer-reviewed scientific papers and found that the overwhelming majority had detected clear evidence of human influence on the climate.

According to Peter Stott, head of climate monitoring and attribution at the Met office, who led the study, "This wealth of evidence we have now shows there is an increasingly remote possibility of climate change being dominated by natural factors rather than human factors."

The study found that since 1980, the average global temperature had increased by about 0.5ºC and that the earth was continuing to warm at the rate of about 0.16ºC a decade.

This trend is reflected in measurements from the oceans. Warmer temperatures had led to more evaporation from the surface, most noticeably in the sub-tropical Atlantic, said Stott.

As a result, the sea was getting saltier. Evaporation in turn affected humidity and rainfall.