Global warming will have an alarming effect on the world over the next 100 years, according to a UN report released yesterday.
By 2100 tropical diseases will have spread into the US, deserts will have expanded across Africa, many of the Alpine glaciers will have disappeared and tropical cyclones will have forced tens of millions of people to flee low-lying parts of Asia, according to the 19-page report by the Intergovernmental Panel on Climate Change, which was conducted by around 700 scientists.
The panel calculates that the "greenhouse effect", caused by unhindered burning of fossil fuels, will cause the Earth's atmosphere to warm by up to 5.8 degrees by 2100.
"Most of the Earth's people will be on the losing side," said Harvard University environmental scientist, Dr James McCarthy, who co-chaired the panel.
The panel noted that effective international action remains elusive, in part because of US reluctance to commit itself to firm targets to reduce greenhouse gas emissions and the push in developing countries such as China towards economic progress.
Despite its political sensitivity - the report was subject to line-by-line scrutiny by government representatives - the report is more precise than any of its UN predecessors about global warming.
The message was frightening, saying the effects of man-made climate change will lead to:
more "freak" weather such as cyclones, floods and droughts;
massive displacement of populations;
potentially enormous loss of life;
greater risk from diseases such as malaria as the mosquito widens its reach;
extinction of entire species as their habitat is wiped out.
The Geneva report followed one released by the panel last month in Shanghai which predicted that global temperatures could rise by as much as 5.8 degrees over the century.
It said the increase was much higher than expected and there was clear evidence that industrial pollution, including emissions from cars, was to blame.
"The greater the rate of change, the more adverse the effect," said World Bank chief scientist and panel chair Dr Robert Watson. "Most warming in the last 50 years is due to human activities. We need to decarbonise our energy sources over the next 50 years."
Ms Frances Maguire of the environmental pressure group, Friends of the Earth, said European governments should "stand firm and force President George W. Bush to agree an effective international deal on cutting emissions."
UN environment talks in the Netherlands collapsed last November, with the US and Europe failing to agree terms for cutting emissions. The talks are to resume in July.