Rain meets rashi

Much before meteorology developed into a science and satellites were sent up into outer space to keep a tab on cloud formations, farmers in India relied on the wisdom of folklore and the movement of planets and stars to predict weather conditions, often with an impressive degree of accuracy.

Taking a cue from the past, Anand Agriculture University (AAU), in Gujarat, in a unique project, has combined meteorology with astrology to understand the moods of the rain gods. Since 2005, AAU has been publishing a 'monsoon panchang', or calendar, which forecasts rains on a particular day.

The predictions are arrived at after taking into account the rainfall records of the past 100 years and the planetary arrangements of 27 nakshatras (constellations) and the nine grahas (planets).

Skeptics, of course, cast doubts over the accuracy of the figures and the methodology, but farmers from far-flung areas in Gujarat have given a warm response to the panchang.

Last year, Dinesh Patel from Navli, near Ahmedabad, was set to sow paddy in his farms, but changed his mind when the panchang showed him that there would be deficit rainfall in 2009. "I went ahead with tobacco instead and it turned out to be a wise decision," he says. Reports suggesting that the monsoon will be delayed this year made Parshottam Patel from Gothda village in Mehsana write to AAU, asking for a copy of the calendar.

Farmers are not only inquiring about the panchang. Some like Parakramsinh Vaghela from Khakharda village in Jamnagar want to know about crop selection and the use of pesticides. His letter to the university read: "Please give me feedback on my choice of crop and also send me the monsoon calendar soon."

Buoyed by such responses, scientists at Anand are mooting a computer model that can synchronise all software and data. An English edition of this panchang is also on the cards.

The rain gods, however, don't always humour these scientists - their self-proclaimed accuracy rate is 85 per cent. The 2010 panchang, which has been generously distributed amongst the farmers in Gujarat, expects 31 per cent more rainfall than is the state average.

"For decades, monsoon forecast was based on statistical models," says AAU vice-chancellor MC Varshneya. "The Indian Meteorological Department adopted a more advanced 16-parameter model in 1988 to track the progress of the season across the country. The model held good till 2002. But in that year, though the model predicted that the month of July would see normal rainfall, many parts of the country witnessed drought-like conditions and agricultural production saw a sharp decline."

Every year AAU scientists and weathermen begin work on the panchang from January. They first sit down with a group of astrologers to prepare kundlis, or horoscopes, of planetary conjunctions. Then, these are interpreted to get an idea of whether a region will get low, medium or high rainfall. For instance, a couple of kundlis indicate that this year Gujarat should receive ample rainfall. Another suggests that the onset of rains maybe delayed, though.

The second step is to marry stargazing with empirical evidence. "Once we are ready with qualitative figures that we prepare through kundlis, we superimpose them with statistical data to make quantitative prediction of rainfall," says Dr HR Patel, a faculty member at the university. "For the past five years, our forecasts have come true, though, with some variations," says Varshneya.