KOCHI: For the third consecutive year, Kerala has reported deficit rainfall during the first half of the Southwest monsoon. The rain deficit, which stood at 36 per cent in June, declined to 26 per cent on July 29, thanks to a bout of heavy rainfall during the third week of the month. The state received 978.8 mm rainfall in July as against the normal rainfall of 1,322.9 mm. The rain deficit was more than 30 per cent in Alappuzha, Kannur, Kollam, Malappuram, Palakkad, Thiruvananthapuram and Wayanad districts.
Though Kerala has been witnessing torrential rainfall during the second week of August for the past three years, the chances of extreme rainfall are scarce this time. “Recently, we have been witnessing monsoon breaks and heavy rainfall for a few days after a short dry spell. Some freak systems may form in the Bay of Bengal which may bring good rains,” said Cusat Advanced Centre for Atmospheric Radar Research Director S Abhilash.
According to the report on Rainfall variability and changes over Kerala by the India Meteorological Department (IMD), there is a decreasing trend in June and July rainfall over the past decade while rainfall in August and September shows an increasing trend.
An analysis of the rainfall data during the past 30 years revealed that there is an increase in rainfall during August in all districts, except Thrissur and Alappuzha. September rainfall shows an increase in all districts except Alapuzha. Though the mean rainfall over the state does not show any significant trend during the Southwest monsoon, July rainfall shows a significant decreasing trend in Kasaragod, Thrissur and Thiruvananthapuram districts.
There has been a significant decline in annual rainfall in, Kasaragod and Kollam districts. The state had witnessed torrential rains during the first two weeks of August during the past three years, which triggered floods and landslides causing extensive loss to life and property. The floods in August 2018 claimed 483 lives and caused an extensive loss of property. The state witnessed two massive landslides at Puthumala and Kavalappara in 2019 in which 121 people were killed.
Pettimudi in the Idukki district witnessed another massive landslide on August 6, 2020, which claimed 70 lives. The area had received 159 cm of rainfall in 96 hours which was the highest precipitation in Munnar since 1924. Meanwhile, the reservoirs have better storage compared to the previous year. Idukki reservoir has 955.76 MCM storage which is 30 per cent more than the storage of 476.44 MCM on the same day last year.