Climate change and its impact on farming dominated the 94th Indian Science Congress this week. The focus in India fell on the recent change in the monsoon rainfall pattern, following from Prime Minister Dr Manmohan Singh’s inaugural address, seeking scientists “to engage in exploring the links between greenhouse gas emissions and climate change”. He also called for upgrading weather forecasting systems to help farmers.

General president of the congress, Dr Harsh Gupta, expressed concern on the rain pattern and its adverse effects on farming. Quoting a recent detailed study by Dr BM Goswami and his colleagues at the Pune-based Institute of Tropical Meteorology, he said: “the study shows a significant rising trend in the frequency and magnitude of extreme rain events and decreasing trend in the frequency of moderate events over central India.

It also points out that the seasonal mean rainfall does not show a significant trend as contribution from extreme event is compensated by a decrease in moderate events.”

The monsoon rainfall system, though quite stable, does show an intricate pattern of space-time variability leading to floods and droughts. The causes of this variability is partly due to heating in the Bay of Bengal and also due to the El Nino phenomenon (warming of Pacific waters). The study called for a twin-view of local and global dimensions of the problem.

In 2005 and 2006, the country had witnessed a unique shift in the monsoon rainfall pattern — heavy rains in drought-prone areas and low rainfall in flood-prone areas. Particularly, the west coast of the country received heavy rain leading to floods at places.

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