As the southwest monsoon made its entry into Karnataka on Tuesday, the Karnataka State Disaster Management Authority’s (KSDMA) data revealed that the pre-monsoon showers were 105% above normal.
Marked by high-intensity rainfall in short periods of time for the most part, the pre-monsoon rain had wreaked havoc in many parts of the State, causing flooding and loss of lives, infrastructure and standing crops.
The KSDMA data show that the departure from normal (1960-2010) for rainfall received between March 1 and May 31 this year is far higher than that in recent years; in 2021, the pre-monsoon rainfall was 44% above normal, and in 2020, 3% above normal rainfall.
237 mm rainfall
The State as a whole received 237 mm rainfall for this period, which, the authority said, is the highest in 51 years (since 1971). As many as 27 districts recorded large excess rainfall, three excess rainfall, and one district recorded normal rainfall (Bidar).
Manoj Rajan, Commissioner, KSDMA said Karnataka’s normal annual rainfall is 1,153 mm; the southwest monsoon brings in 74%, 16% is received during the northeast monsoon and 10% during pre-monsoon.
As the southwest monsoon arrives, having recorded large departures from normal in recent years, Dr. Rajan said the variability of southwest monsoon rainfall has also increased significantly since 1960. “Several districts are seeing an increase in prolonged dry periods with low or no rainfall or intermittent with short, intense spells of rainfall.
The study of long-term climate data series for the last 58 years shows that there has been a considerable shift in rainfall patterns over Karnataka. The quantum, intensity and distribution of rainfall have varied across the regions in the State from the 1960-1990 period (P1) to 1991-2017 (P2),” he said.
Highs and lows
Kodagu, Kalaburagi, Yadgir, Dakshina Kannada and Uttara Kannada districts show a reduction in annual rainfall, while and an increase in rainfall has been observed over Shivamogga and Hassan districts from P1 to P2, he explained.
