With the rabi season around the corner, a countrywide forecast prepared at the end of the monsoon season suggests deficit soil moisture conditions are likely in Gujarat, Bihar, Jharkhand, Tamil Nadu, and southern Andhra Pradesh.
This forecast, following a joint exercise by IIT Gandhinagar and the India Meteorological Department (IMD), for the first time, provides a country-wide soil moisture forecast at seven and 30-day lead times.
How was it developed?
The experts used the ‘Variable Infiltration Capacity’ model to provide the soil moisture prediction.
The product, termed ‘Experimental Forecasts Land Surface Products’, is available on the IMD website. It has been developed using the hydrological model that takes into consideration soil, vegetation, land use and land cover among other parameters.
In Bundelkhand, most farmers keep their land fallow or just grow some fodder crop during the kharif season since the rains are unpredictable and there could be extended dry spells after sowing. They then mainly cultivate the rabi crop using the soil moisture left behind by the monsoon rains.
It is a similar trend in Bihar, in low lying areas of Seemanchal and Kosi belt, where no crop is grown during Kharif because of inundated lands. This means that if there is not enough rainfall in one or two months, these are regions which will demand heavy irrigation whether that comes from groundwater or surface water storage (reservoirs).
Based on observed conditions at present, Gujarat, parts of Maharashtra, Chhattisgarh, Jharkhand, Tamil Nadu and parts of Andhra Pradesh are deficient in terms of soil moisture right now.
Significance and the need for data on soil moisture:
Soil moisture is crucial for agriculture since it directly affects crop growth and how much irrigation is required for the area. It is because the crucial information needed for agriculture is not revealed only through rainfall data.
Soil moisture gives us more information on what is needed for crop growth in different parts of the country. Besides, timely soil moisture forecasts will help target interventions, in terms of seed varieties for better planning in agriculture.