Forecasting the June-to-September rains, which account for three-quarters of India’s annual rainfall, is becoming tougher. Last year, six states had to declare droughts despite predictions of a normal monsoon.

Although India is scaling up its prediction techniques, including joint Indo-American forecasting under a bilateral agreement, too little is understood about how pollution and rising temperatures are impacting the monsoon. But new research shows that they are surely having an impact on the climate.

“Our studies show the Indian Ocean has significantly warmed in 50 years. By about 0.6 degrees. Monsoon has been declining in the Western Ghats, and interior areas, such as Jharkhand and Chhattisgarh, by about 6-7%,” R Krishnan, a climatologist at the Indian Institute of Tropical Meteorology, Pune, told HT.

Krishnan also said that a weakening monsoon circulation has quickened the “warming of the equatorial India Ocean” and this, in turn, has contributed to a “further weakening of the monsoon”.

The new findings portend problems India isn’t currently prepared to address. Two-thirds of Indians rely on rain-fed farm income. The monsoon also replenishes 81 nationally monitored water reservoirs critical for drinking, power and irrigation. A changing monsoon could hurt millions of farmers.

Yet another published study, by Dr Veerabhadran Ramanathan of the University of California, San Diego, notes that climate change has “evidently already negatively affected India’s hundreds of millions of rice producers and consumers.”

Initial breakthroughs, such as identifying some heat-resistant wheat varieties, are too small to make any impact.