Half the world's population could face a shortage of clean water by 2080 because of climate change, experts warned yesterday.

Wong Poh Poh, a professor at the National University of Singapore, told a regional conference that global warming was disrupting water flow patterns and increasing the severity of floods, droughts and storms, all of which reduce the availability of drinking water.

Wong said the United Nations Intergovernmental Panel on Climate Change found that as many as 2 billion people won't have sufficient access to clean water by 2050. That figure is expected to rise to 3.2 billion by 2080, nearly tripling the number who now do without it.

Reduced access to clean water, which refers to water that can be used for drinking, bathing or cooking, forces many villagers in poor countries to walk miles to reach supplies.

Others, including those living in urban shanties, suffer from diseases caused by drinking unclean water.

At the beginning of the decade, the World Health Organization estimated that 1.1 billion people did not have sufficient access to clean water. Asia, home to more than 4 billion people, is the most vulnerable region, said Wong, a member of the UN panel.

"In Asia, water distribution is uneven and large areas are under water stress. Climate change is going to exacerbate this scarcity," he told the two-day Asia Pacific Regional Water Conference attended by policy makers, government officials, academics, businessmen and consumer group representatives.

Scientists have said global climate change takes many forms, causing droughts in some areas while increasing flooding in others.

Droughts reduce water supply, and floods destroy the quality of water. Rising sea levels, for instance, increase the salt content at the mouths of many rivers, from which many Asians draw their drinking water.

Wong and others at the conference called on governments to embrace the Kyoto Protocol climate treaty to fight global warming and protect water resources as a short-term solution.

(Shanghai Daily via Agencies November 19, 2008)