World climate experts have issued their bleakest forecasts yet on the effects of climate change, predicting that it will inflict damage on every continent but hit the world's poor disproportionately hard.

In a 1,400-page report, the UN's Intergovernmental Panel on Climate Change (IPCC) warned that almost a third of the world's species could be wiped out by global warming.

The report's accompanying summary was agreed this morning after experts and officials wrapped up a week of talks in Brussels with a marathon 24-hour negotiating session. Delegates said that the United States, China and Saudi Arabia provoked charges of political interference by objecting to the scientists' tough wording.

Some scientists even vowed never to take part in the process again. “The authors lost,” said one, who did not want to be named because the process is confidential. “A lot of authors are not going to engage in the IPCC process anymore. I have had it with them.”

“But don’t be misled,” added another source. “The data is all there in the main report -- this is a very strong message."

The IPCC said that damage to Earth’s weather systems from greenhouse gases will change rainfall patterns, punch up the power of storms and boost the risk of drought, flooding and stress on water supplies.

This will have consequences that, according to the level of carbon pollution that stokes global warming, will be adverse or, in some scenarios, even catastrophic. Those consequences range from increased famine in Africa to thawing glaciers in the Himalayas.

“Poor people are the most vulnerable and will be the worst hit by the impacts of climate change. This becomes a global responsibility,” Rajendra Pachauri, the IPCC's chairman, declared.

Up to 30 per cent of animal and plant species will be vulnerable to extinction if global temperatures rise by 1.5-2.5 degrees Celsius (2.7 to 4.5 Fahrenheit), the IPCC said. No continent can expect to be unscathed by even a relatively modest increase in temperatures.

“It is very likely that all regions will experience either declines in benefits or increases in costs for increases in temperature greater than 2 to 3 degrees” (C), or 3.6-5.4 F, over 1990 levels, according to a “summary for policymakers” agreed by the IPCC.

The IPCC report predicts that billions of people will face water scarcity and hundreds of millions are likely to go hungry, mainly in the poorest regions least to blame for spewing the fossil fuel pollution that scientists believe are driving up temperatures.

At US insistence, drafters of the summary dumped a paragraph that said North America was“expected to experience severe local economic damage and substantial ecosystem, social and cultural disruption”, delegates said.

Poor tropical countries will be hit worst, according to a draft of the main report.

Worsening water shortages in drought-prone countries, malnutrition caused by desiccated fields, property damage from extreme weather events and the spread of disease by mosquitoes and other vectors will amount to a punishing bill that is beyond the ability of vulnerable countries, especially in Africa, to pay.

Biodiversity and natural habitat are in for a hammering. Even a modest increase in temperatures will bleach many coral reefs, reduce part of eastern Amazonia to a parched savannah, thaw swathes of the northern hemisphere’s permafrost, change seasons for plant pollination and animal reproduction.

The report is part of the IPCC’s first assessment in six years of the evidence for climate change. In the first volume of this review, issued in February, the IPCC said Earth’s temperature had already risen by 0.74 C (1.33 F) in the past century.

By 2100, it could rise by between 1.1 C (1.98 F) and 6.4 C (11.52 F) compared to 1980-99 levels, with a likely range of 1.8 C to 4.0 C (3.2-7.2 F).

Explore World News

• World Agenda

• Iraq News

• US & Americas News

• Europe News

• Middle East News

• Afghanistan News

• Asia News

• Africa News

• Ireland News

Times Recommends

• No apology for Germany’s own Nazi victims
• Intricate web of fear and hope tying down deal
• Victims remembered a year after Mumbai attacks