Global warming is not a future apocalypse, but a present reality for many of the world's poorest people, according to the most hard-hitting United Nations report yet on climate change, published yesterday.

A catalogue of the "climate shocks" that have already hit the world is set out in the Human Development Report 2007/08. Fewer than two per cent of these have affected rich countries. Europe had its most intense heatwave for 50 years and Japan its greatest number of tropical cyclones in a single year. But far more intense drought, floods and storms than usual have plagued the developing world.

Monsoons displaced 14 million people in India, seven million in Bangladesh and three million in China which has seen the heaviest rainfall – and second highest death toll – since records began. Cyclones blasted Indonesia, the Philippines and Vietnam. Hurricanes devastated the Caribbean and Central America, killing more than 1,600 Mayan people in Guatemala. Droughts have afflicted Africa, driving 14 million people from their homes.

In the rich world, insurers report a fivefold increase in climate-related insurance claims. In the poor world the cost is counted in terms of hidden human suffering, for most disasters are under-reported.

Based on new climate modelling, the UN report has a number of strong messages. It is highly critical of US, EU and British policies on global warming – it says the measures in Gordon Brown's Climate Change Bill are "not consistent with the objective of avoiding dangerous climate change".

However, its top-line message is that the fixation of campaigners like Al Gore with a long-term "we're all doomed" vision of global warming has diverted attention from more immediate threats.

Already, its new research shows, children born in Ethiopia in years of drought are 41 per cent more likely to be stunted from malnutrition than those born in a time of rains. That has already created two million more malnourished children – and this is not an affliction that is shaken off when the rains return. It creates cycles of life-long disadvantage.

The report shows how climate shocks force the poor to adopt emergency coping strategies – reduced nutrition, withdrawal of children from school, cuts in health spending – which damage the long-term health of entire societies.

After 150 years in which human well-being has steadily improved, the world is now facing the prospect that progress on indicators such as poverty, nutrition, literacy and infant mortality will be arrested. "It may even be reversed," said the report's lead author, Kevin Watkins, who was formerly head of research at Oxfam.

The report says George Bush's home-state of Texas (population 23 million) has a bigger carbon footprint than the whole of sub-Saharan Africa (population 720 million).

The report also criticises Britain's policy on climate change. The UK is the world leader on rhetoric, it says, yet "if the rest of the developed world followed the pathway envisaged in the UK's Climate Change Bill, dangerous climate change would be inevitable".

The report says two things need to be done. Rich nations need to massively cut emissions (by at least 80 per cent) and developing and emerging nations need to make modest cuts (of around 20 per cent). Also, large amounts of money are needed to adapt to the consequences of climate change. Hardly anything is being spent in the poor world, where people were least responsible for global warming but suffer most. The amounts donated to the UN's climate change mitigation fund have been equivalent to only one week's worth of spending under the UK's flood defence programme.

(By Paul Vallely, The Independent, 28/11/2007)