Thanks to global warming, soon you may not see the monsoon rains, which in normal circumstances hit the Kerala coast around June 1 every year. Again, you may not see the crops which normally come to the market during harvest season.

If you go by the words of renowned British economist Sir Nicholas Stern, the scene is alarming. India's monsoon, the biggest source of water for irrigation, is likely to be disrupted by the melting of glaciers and snow on the Himalayas due to global warming.

In an interview released by the World Bank, Stern said global warming may result in the melting of glaciers and snow on the Himalayas and "we don't know what effect that will have on the monsoon, and it could have quite a strong effect."

India depends on the June-September monsoon to replenish reservoirs and underground water systems. Monsoon accounts for four-fifths of India's annual rainfall and help meet both drinking water and farm requirements. And any climate change can erode farm output. Increase or decrease in rains will definitely hit the crops across India.

Stern added, "The poor people of India depend particularly on agriculture. In terms of poverty impact, it is much bigger. If it gets more difficult in terms of carrying out irrigation and with disruption in the monsoon, a big fraction of the Indian population will be affected. That is why it is important to control climate change as much as we can."

According to Stern, developed countries must cut emissions caused by burning oil and coal by 60 per cent to 80 per cent by 2050 to prevent famine, destruction of coral reefs and the disappearance of glaciers. Climate change may cost the world as much as 20 per cent of its gross domestic product, $9.6 trillion at today's prices, by the next century.

In the past few years, India had erratic rainfall during the monsoon season. In 2002, India had its worst drought since 1987, paring economic growth to a decade low of 4 per cent. Last year, monsoon was normal.

Stern compared the Himalayas to a sponge, moderating the impact of precipitation as seasons change. "Precipitation comes, and it's held there. That's how India gets water in the rivers. That effect will not be there if the glaciers and snow are not there. Which means you'll get torrents during the wet season and dry rivers in the dry season. So you'll get a combination of flood and drought," he warned.

"We have to adapt how we handle water extraction, and irrigation. Water management is involved in all of this. Work has to be done on what crops would be resilient," Stern said. Urban areas throughout the region are also at risk, as water supplies could be disrupted over time. Infrastructure must be upgraded for sanitation.

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