BENGALURU: Karnataka has been witnessing a drastic change in rainfall pattern and distribution over the past two decades, resulting in frequent
drought,
floods and untimely rain.
According to a study by the Karnataka State Natural Disaster Monitoring Centre (KSNDMC), north Karnataka and coastal areas have been g a declining trend in rainfall, besides a very high fluctuation in rain distribution.
The state has reeled under 11 years of drought and two years of floods since 2000.
A good example of this was 2018 when the state had to deal with floods and drought. “Karnataka is perhaps the only state in the country to be declared both drought- and flood-hit in the same year. It’s mainly because of drastic change in rainfall distribution,” said GS Srinivas Reddy, director, KSNDMC.
While most districts of north Karnataka and south- interior Karnataka faced drought in 2018, Kodagu, Chikkamagaluru, Dakshina Kannada and Udupi districts and parts of Shivamogga were hit by floods and incessant rain. In fact, Kodagu and parts of Chikkamagaluru bore the brunt of rain fury.
Reddy said drought and floods were occurring not because there’s a drastic decline or increase in rainfall. As per analysis of data since 1991, there’s been an average decline of just 2.5mm of rain during the southwest monsoon and 4.2mm in the northeast monsoon. A 4mm decrease in rain is equal to loss of 1 tmcft of water, which is insignificant compared to the state’s annual rain yield.
In a year, Karnataka receives 1,135mm of rain and the south-west monsoon accounts for 73% of it. Since 2011, the state has received an average rainfall of 1,033 mm, that’s 10% less than normal.
Even north-interior Karnataka received good rainfall with an average of 593mm against the annual rainfall of 712mm.
It shows that distribution of rainfall, not quantity, is the problem. In 2015, the state received good rainfall in April and early May facilitating good sowing. But rain stayed away in July and August when it was needed the most. It’s been happening for the past few days too, Reddy added.