Climate change is forcing growing numbers of people in the developing world to flee their homes and seek refuge abroad, the United Nations High Commissioner for Refugees warned today.

Announcing findings that the number of refugees worldwide had risen steeply for the second year running, António Guterres said that environmental degradation induced by climate change was forcing greater displacement as resources became increasingly scarce.

The UNHCR’s 2007 Global Trends report says the number of international refugees under its responsibility rose from 9.9 to 11.4 million by the end of last year. Meanwhile the number of people displaced internally by conflict increased from 24.4 million to 26 million, according to the Internal Displacement Monitoring Centre. "After a five-year decline in the number of refugees between 2001 and 2005, we have now seen two years of increases, and that's a concern," Mr Guterres said.

"We are now faced with a complex mix of global challenges that could threaten even more forced displacement in the future,” he warned. “They range from multiple new conflict-related emergencies in world hotspots to bad governance, climate-induced environmental degradation that increases competition for scarce resources, and extreme price hikes that have hit the poor the hardest and are generating instability in many places."

Competition for natural resources has long been a source of conflict in the developing world, particularly on the African continent. Now, as climate change exacerbates environmental degradation, access to water and fertile land is becoming ever more scarce, feeding displacement either directly, as communities relocate in search of resources, or indirectly through conflict, poverty and food shortages.

Darfur, where 2.5 million people have been displaced by conflict, was a case in point, Peter Kessler of the UNHCR told The Times. “The root of the conflict is greatly due to the competition for water and grazing land between tribes.”

Sudan has become one of the world’s refugee hotspots, with over half a million having fled the country in search of a better life elsewhere, according to UN figures.

“We are seeing right across the planet, particularly in the developing world, that climate change is generating levels of environmental degradation and wearing down the life support systems on which millions of people depend,” Nick Nuttall of the United Nations Environment Programme told The Times.

“Whereever you look, the footprint of climate change and environmental degradation is bring people to a situation where resources are increasingly scarce and forcing them to move.”

Mr Nuttall pointed to Uganda’s Rwenzori mountains, where retreating glaciers were threatening the existence of rivers – including the Nile - on which millions of people depended for their livelihood. In Haiti, he said, deforestation and the resulting erosion of fertile topsoil was contributing to conflict, while in Mali, Chad and Ethiopia, entire lakes had all but disappeared over the last two decades.

Meanwhile in Asia, the Himalayan glaciers which fed the continent’s life-supporting rivers could have all but vanished by 2030, he added.

In India, preparations to stem the flood of ecological refugees are already underway. The government is currently constructing a 2,500 mile barrier along its border with Bangladesh, from which it already sees a substantial flow of illegal immigrants. In this low-lying nation, rising sea levels and storm surges could force 34 million people to flee their homes over the next several decades.

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