IMD must aim for micro-level forecasts

The India Meteorological Department’s (IMD) prediction of a normal monsoon this year might bring some cheer, though the impact of normal rains may be different in Covid-hit times from normal years. The met agency expects the precipitation to be "most likely’’ in the range of 96-104 % of the Long Period Average (LPA), which is the mean of the rainfall during the 1961-2010 period. The monsoon was above normal in the last two years at 110 % and 109 % of the LPA, though the IMA had predicted normal monsoons. The monsoon helped the economy last year with a strong performance by the agricultural sector, which was the only sector to perform. A normal monsoon would keep inflation in check, increase farm production, boost rural employment and incomes and create more demand. But it is yet to be seen how these factors would work if the pandemic situation gets worse and spreads to more areas including the rural hinterland.

The most important factors that decide the quantum of the monsoon are the surface temperatures in the Pacific and the Indian Ocean. The IMD has foreseen them as "neutral’’ this year. The El Nino phenomenon, which refers to the abnormal warming of the waters of the equatorial Pacific, is unlikely to be adverse. The parameters on the Indian Ocean also point to the possibility of normal rains. Therefore the IMD thinks that its forecast may not be off the mark. But, as always, the spatial distribution of the monsoon will be uneven across the country. While central and southern India are likely to get above normal rain, Jharkhand, Odisha, Bihar and the North-Eastern states may not receive adequate rain. Rainfall may also be below normal in some areas of North India including Delhi and Jammu Kashmir.

The IMD makes its predictions in two stages. The preliminary forecast is made in April and a more detailed one, which gives estimates of the amount of rainfall in four regions and in the months of July and August, are given in May or early June. This year there will be separate forecasts for the monsoon core zone, which most depends on the monsoon for agriculture, and for the months of June and September too. The IMD has made many technological improvements this year to reduce the margin of error. It should also try to make micro-level forecasts which will be more useful to the farmers and others. Now that there is a fair idea of the nature of monsoon this year, governments should be ready to deal with them. The fight against the pandemic will claim most attention, but that should be no reason for departments like agriculture and disaster management to lose their focus.