WASHINGTON: A new UN report suggests that climate change will displace hundreds of millions of people by the end of this century, increasing the risk of violent conflict and wiping trillions of dollars off the global economy.

The second of three publications by the UN's Intergovernmental Panel on Climate Change, due to be made public at the end of this month, is the most comprehensive investigation into the impact of climate change ever undertaken.

A draft of the final version seen by the Independent says the warming climate will place the world under enormous strain, forcing mass migration, especially in Asia, and increasing the risk of violent conflict.

Based on thousands of peer-reviewed studies and put together by hundreds of respected scientists, the report predicts that climate change will reduce median crop yields by 2 percent per decade for the rest of the century - at a time of rapidly growing demand for food. This will in turn push up malnutrition in children by about a fifth, it predicts.

The report also forecasts that the warming climate will take its toll on human health, pushing up the number of intense heatwaves and fires and increasing the risk from food and water-borne diseases.

According to the draft report, a rare grassy coastal habitat unique to Scotland and Ireland is set to suffer, as are grouse moors in the UK and peatlands in Ireland. The UK's already elevated air pollution is likely to worsen as burning fossil fuels increase ozone levels, while warmer weather will increase the incidence of asthma and hay fever.

The report predicts that by the end of the century "hundreds of millions of people will be affected by coastal flooding and displaced due to land loss".

The majority affected will be in east Asia, southeast Asia and south Asia. Rising sea levels mean coastal systems and low-lying areas will increasingly experience submergence, coastal flooding and coastal erosion.