.........BENGALURU: The spell of monsoon appears to be going from bad to worse as one of the wettest months in the year in prime catchment areas is turning out to be unnaturally dry. Despite the deluge in Bengaluru owing to heavy downpour in parts of South Interior Karnataka, rainfall has been deficient by 38 per cent in the first half of August.
Malnad and coastal regions of the state, which form the prime catchment areas, have received less than half the rainfall till August 17, leading to reduced inflow to reservoirs in Cauvery and Tungabhadra basins. As a result, water levels in reservoirs, especially in the Cauvery basin, continued to remain lower than their levels on the same date last year.
Forecasts, however, indicate some change in fortune for coastal and Malnad regions in terms of rainfall over the next week, which will likely improve inflow to the reservoirs.
According to data, Malnad and coastal regions have had rainfall deficiency in excess of 50 per cent in August. Though South Interior Karnataka too was receiving less rainfall, the deficiency for the month was offset by the heavy showers recorded in Bengaluru Urban and other districts of the region during the week.
An early onset of monsoon has not translated into good showers. While the overall deficiency in the state till date is 27 per cent, the Malnad region has a deficiency of at least 31 per cent. Apart from reduced inflow, the long dry spells between the showers have also impacted the moisture content of soil, which is crucial for successful cultivation of crops.
Effect of pollution
G S Bhat, professor at Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, told Express that among the factors contributing to reduced rainfall was an increase in suspended air particles.
While suspended particles such as salt, dust or pollen are crucial for the formation of rain droplets in the clouds, the process gets hampered if there are too many particles. As a result, the size of the rain droplets formed will not be big enough to reach the ground. This can be seen when dark clouds appear to cause rain but disappear without a single drop hitting the earth, he said.