Indian monsoon likely to decline on global warming: Report

07 Nov 2012 Evaluate

Indian monsoon is reportedly set to decline on global warming caused by human interference, which is likely to affect agriculture in the next 200 years. The decline in rainfall by 40-70% would be extremely unfavorable to India’s economy which depends heavily on the monsoon season to bring fresh water to the farmlands, affecting food supplies in the country.

The study suggests that increased human activity like burning of fossil fuels and related shifts in tropical air flows, which has lead to drastic climate change, could result in collapse of monsoon rains about every 5th year between 2150 and 2200.

India’s monsoon period (June to September), which is essential for the country’s growing crops such as rice, wheat and corn. The South-West monsoon accounts for more than 70% of rainfall in India. The researcher’s simulations illustrate that as temperatures increase in the future, the Walker circulation, on average, brings more high pressure over India, even though the occurrence of El Nino doesn’t increase.

Almost 200 nations have promised to limit global warming to below 2.0 degrees C (3.6 F) above pre-industrial times to avoid dangerous changes such as more droughts, floods and rising sea levels. But world emissions are rising and the 2 degree ceiling is getting difficult to pull off. Higher temperatures will mean that more water evaporates from the oceans, increasing rains in many areas.

The immediate effects of climate change on monsoon rainfall have already been observed by the researchers; however, the patterns of response in the coming decades are not uniform across different models and studies.