World - Thinning Himalayan glaciers may deprive half billion Indians of water

Washington, Nov 19 (IANS) The absence of radioactive signals from all the three ice core drilled in a Himalayan glacier bodes ill for half billion people living downstream in India. They indicate that high-altitude glaciers are no longer accumulating ice due to climate change. This could hit future water supplies.

These missing markers of radiation are remnants from atomic bomb tests a half-century ago, as in the Naimona'nyi glacier in Tibet.

Seasonal runoff from glaciers like Naimona'nyi feeds the Indus, the Ganga and the Brahmaputra rivers.

In some places, for some months each year, those rivers are severely depleted now, researchers said. The absence of new ice accumulating on the glaciers will only worsen that problem.

Lonnie Thompson, professor of earth sciences at Ohio State University (OSU), feared that other high altitude glaciers like the 6,050-metre-high Naimona'nyi glacier may be facing similar problems.

'I think that this has tremendous implications for future water supplies in the Andes, as well as the Himalayas, and for people living in those regions.'

'When you think about the millions of people over there who depend on the water locked in that ice, if they don't have it available in the future, that will be a serious problem,' he said.

'The current models that predict river flow in the region have taken recent glacial 'retreat' into account,' said Natalie Kehrwald, doctoral student at OSU and co-author of the paper. 'But they haven't considered that some of these glaciers are actually thinning.'

The researchers' recent work has shown similar thinning on glaciers in Africa and South America in the past few years, according to an OSU release.

Working on the project with Thompson and Kehrwald were professor of geography Ellen Mosley-Thompson, Mary Davis, and Yao Tandong, of the Institute for Tibetan Plateau Research with the Chinese Academy of Sciences.

These findings were published in Geophysical Research Letters.