Current projections indicate that rainfall might increase by five per cent to 25 per cent all over the tropics in the next 25 to 30 years on account of climate change, according to Ajit Tyagi, Director-General, India Meteorological Department.

Talking to The Hindu after speaking at a session on “Climate change implications on socio-economic development” at the ongoing Geospatial World Forum-2011 here on Wednesday, he said that although climate change had not impacted the monsoon system, projections indicated that it would be affected. The trend during the last 30 years showed a decrease in rainfall in the eastern parts of the country and an increase in the western region.

Although there had been a distinct rise in temperatures since 1970, the rate of increase in the last 15 years was higher in the country compared to the preceding 15 years. While the rise in temperature was 0.2 degrees Centigrade during 1991-2,000, it was 0.4 deg C between 2001 and 2010. Seven or eight of the last 10 years were the warmest. “This can't be attributed to natural variability,” he said.

The IMD was modernising its observational infrastructure and predictive capability by putting in place 55 Doppler radars and 4,000 automatic weather stations, among other measures, all over the country.

Subodh Sharma, adviser, Ministry of Environment and Forests, in his presentation at the forum, talked about the Indian Network for Climate Change Assessment (INCCA). He said the temperatures over the Indian region showed an increase of 0.4 deg C in the last 100 years and there was a rise in sea level at the rate of 1.06-1.25 mm/year over the last 40 years.

According to projections, there would be a 15-40 per cent increase in rainfall in India, with high regional variability, and a rise in the mean annual temperature by 3 deg C to 6 deg C by the end of the 21{+s}{+t} century. Referring to the impact of climate change on health, he said the rise in temperature was projected to increase the occurrence and spread of malaria.