The New Nation - Internet Edition

AFP, Valencia

The world's leading authority on climate change adopted Saturday a landmark report that warns that the impacts of global warming are already visible, will accelerate this century and are potentially irreversible.

"The parties to the governments adopted the full report, consisting of a shorter synthesis and a longer version," said Jose Romero, a Swiss delegate and one of the reports many authors.

The document, to be formally presented later Saturday in the Spanish city of Valencia by UN chief Ban Ki-moon, encapsulates the Intergovernmental Panel on Climate Change's latest findings on the effects of greenhouse gases. It seeks to guide politicians facing tough decisions on cutting pollution from fossil fuels, shifting to cleaner energy, bolstering defences against extreme weather, and other issues set to intensify due to climate change.

Ban warned Saturday in a published commentary to the first IPCC overview since 2001 that the world was on the verge of a "catastrophe" due to global warming. The draft report from the Nobel-winning IPCC, which was not expected to change significantly, said the evidence of a human role in the warming of the planet was now "unequivocal." Retreating glaciers and loss of snow in Alpine regions, thinning Arctic summer sea ice and thawing permafrost shows that climate change is already on the march, it said.

By 2100, global average surface temperatures could rise by between 1.1 C (1.98 F) and 6.4 C (11.52 F) compared to 1980-99 levels, while sea levels will rise by between 18 and 59 centimetres (7.2 and 23.2 inches), it forecasted.

Heatwaves, rainstorms, tropical cyclones and surges in sea level are among the events expected to become more frequent, more widespread or more intense this century.

"This is the strongest document the IPCC has produced," said Hans Verolme, director of the World Wildlife Fund's Global Climate Change Program. He said that the synthesis said more clearly than any previous version, for example, that global warming was likely to be "irreversible".

"It is a tremendous result -- the overwhelming scientific evidence of climate change is here. Now the ball is in the court of politicians." "All countries" will be affected, but poorer countries -- ironically those least to blame for causing the problem -- will be hit hardest and they have the least resources for coping, according to the draft report.

Publication of the report comes in the run-up to a December 3-14 conference in Bali, Indonesia, where the world's nations will gather to ponder the climate crisis. The UN Framework Convention on Climate Change (UNFCCC) is tasked with setting a "roadmap" of negotiations for intensifying cuts in carbon emissions beyond 2012, when the Kyoto Protocol runs out.

Carbon pollution, emitted especially by the burning of oil, gas and coal, traps heat from the Sun, thus warming the Earth's surface and inflicting changes to weather systems.

Emissions are spiralling, driven more recently by coal-fired plants in fast-growing China and India.