IMD is happy to declare a monsoon as normal as long as total quantum of rainfall at national scale is within 4% of what is defined as normal monsoon rainfall during June 1 to Sept 30. Even if this means there is spatially or temporally or both spatially & temporally, the total rainfall or its distribution is abnormal in large parts of the country. It was good to see a national newspaper, asking question if the monsoon is normal even though it’s not temporally normal as was the case in large parts of the country this year.
The IMD normal only assures meteorological normal of national monsoon rainfall within given period. It does not assure hydrologic normal nationally or in different parts of the country, nor agricultural normal rainfall nationally or in different parts: sub divisions, states, river basins, districts, talukas/ tehsils or villages and wards. We clearly need much more realistic and nuanced definition of even meteorological Normal monsoon rainfall, which IMD needs to work on. But as far hydrological or agricultural normal rainfall is concerned, both temporally and spatially, those concerned outside IMD will need to work on.
Continue reading “DRP NB 14 Sep 2020: How should we define a Normal Monsoon?”