Heating will be most marked in the Arctic

It means that delegates to The Hague climate change conference, from 13 to 24 November, will be provided with a detailed prediction of what may happen to their countries if the atmosphere continues to warm as it appears to be doing now.

The study finds that parts of central Asia, where temperatures already regularly exceed 40 degrees C, can expect some of the biggest rises ahead.

It says there will be increases of more than five degrees C in countries from Kazakhstan to Saudi Arabia, several of them affected this year by famine.

Next in line are a number of countries in West Africa which are also prone to drought.

National wealth

Among countries expected to warm by between four and five degrees C are India, Egypt and the US.

The study bears out earlier predictions in confirming that the Russian and Canadian Arctic should expect the largest temperature rise - more than six degrees C by 2100.

Those likely to warm least - three degrees C or less - are the UK and Ireland in the Northern Hemisphere, and Argentina, Uruguay, Chile and New Zealand in the south.

The researchers also divided each country's national wealth by its predicted temperature rise to assess the probable impact of warming on its population.

By this criterion, the four most vulnerable countries in the world are Afghanistan, Ethiopia, Sierra Leone and Tanzania.

Vulnerability index

They have just $100 of their gross national product for each citizen to spend on coping with every degree of warming.

Saudi Arabia will heat significantly

The least vulnerable country, by contrast, is Luxembourg, which can spend $8,800 per head.

The researchers acknowledge that temperature is only one index of climate change, and that a country's GDP cannot capture every dimension of vulnerability to it.

But the Tyndall Centre's director, Dr Mike Hulme, said that, almost without exception, the countries threatened most starkly by global warming produced the smallest amounts of the greenhouse gases believed to be causing it.

He said: "What this analysis shows is the relation between how much carbon each block of countries emits and how vulnerable they are to climate change. It highlights the disparity between rich and poor nations.

"The climate conference will focus on the richer nations who must act now to start reducing their emissions. This is the main issue facing ministers at The Hague."