Top scientists meet in Paris

Paris - The world's top climate experts were geared for a four-day meeting beginning Monday in Paris where they are set to launch a long-awaited update about the scientific evidence for global warming.

The report is the first by the UN's Intergovernmental Panel on Climate Change (IPCC) since 2001 and the fourth since the body was launched in 1988.

The IPCC's reports are highly regarded for their neutrality and caution, and they wield a big influence over government policies, corporate strategies and even individual decision-making.

In 2001, the IPCC declared that carbon pollution from burning oil, gas and coal had helped drive atmospheric levels of CO2 to their highest in 420 000 years.

CO2 is the principal "greenhouse gas," a term that applies to half a dozen gases that linger invisibly in the atmosphere, trapping the Sun's heat instead of letting solar radiation bounce back into space.

Over the previous 50 years, temperatures climbed by around 0.1°C per decade and most of the warming could be attributed to Man, the 2001 report said.

It predicted that by 2100, the global atmospheric temperature will have risen between 1.4 and 5.8°C and sea levels by 0,09 to 0,88 m, depending on how much greenhouse gas is emitted.

Basing their judgement on a mountain of climate studies that have been published since then, the experts are expected to fine-tune these two range estimates.

They are also expected to point to fresh evidence that change is already happening and could accelerate.

Recent signs of damage to the climate system have been shrinking glaciers and snow cover in high mountains, a retreat of the North Pole's sea ice in summer and acidification of the seas caused by absorption of atmospheric CO2.

The report, to be issued on Friday after the four-day meeting, is agreed by consensus among the some 500 scientists and government representatives in the IPCC's Working Group 1.

Two other volumes will be issued in April in what will be the fourth assessment report on climate change by the IPCC since it was established in 1988. The two others will focus on the impacts of climate change and on the social-economic costs of reducing greenhouse gases. - Sapa-AFP