Global warming hits Himalayas

Nawa Jigtar was working in the village of Ghat, in Nepal, when the sound of crashing sent him rushing out of his home. He emerged to see his herd of cattle being swept away by a wall of water.

Jigtar and his fellow villagers were able to scramble to safety. They were lucky: 'If it had come at night, none of us would have survived.'

Ghat was destroyed when a lake, high in the Himalayas, burst its banks. Swollen with glacier meltwaters, its walls of rock and ice had suddenly disintegrated. Several million cubic metres of water crashed down the mountain.

When Ghat was destroyed, in 1985, such incidents were rare - but not any more. Last week, scientists revealed that there has been a tenfold jump in such catastrophes in the past two decades, the result of global warming. Himalayan glacier lakes are filling up with more and more melted ice and 24 of them are now poised to burst their banks in Bhutan, with a similar number at risk in Nepal.

But that is just the beginning, a report in Nature said last week. Future disasters around the Himalayas will include 'floods, droughts, land erosion, biodiversity loss and changes in rainfall and the monsoon'. [...]

'A glacier lake catastrophe happened once in a decade 50 years ago,' said UK geologist John Reynolds, whose company advises Nepal. 'Five years ago, they were happening every three years. By 2010, a glacial lake catastrophe will happen every year.'