Cloudbursts, flash floods and landslides claimed 42 lives in southern Kerala districts of Idukki, Pathanamthitta and Kottayam between October 12 and 19. The unusual weather events rendered hundreds of people homeless. It forced around 4,000 families living in disaster-prone areas to leave their homes and seek refuge in relief camps set up by the state government.
The state continues to be on high alert after the India Meteorological Department (IMD) warned of heavy rains till October 23.
Kerala has been experiencing such extreme weather events since 2016. That year’s drought was followed by Cyclone Okchi in 2017 and back-to-back floods and landslides in 2018 and 2019.
Dr S Abhilash, Director of Advanced Centre for Atmospheric Radar Research at the Cochin University of Science and Technology (CUSAT), while participating in a discussion by Onmanorama in Kochi on October 19, said that extreme weather events have become a new normal in Kerala. “Weather patterns are becoming erratic and the stability of the system is deteriorating,” he said.
He said the October 16 landslides and flash floods in Koottickal and Mundakkayam were similar to those that happened in Kavalappara (Malappuram district) and Puthumala (Wayanad district) in 2019.
He said changes in the structure of rain-bearing clouds are a cause for concern. “Normally, we get shallow types of clouds during monsoon season. That is being changed. Clouds that overshoot 7km and grow beyond 10km produce thunderstorms. They are known as cumulonimbus clouds. We observed a large number of cumulonimbus clouds in 2019 in Kavalappara and Puthumala. The unusual formation of a convective system is the reason for cloudbursts (10cm rainfall in just one hour) and mini cloudbursts (5cm rainfall in two hours). The cloudbursts cause landslides,” he said.
Dr T V Sajeev, Principal Scientist and Registrar at Principal Scientist and Registrar at the Kerala Forest Research Institute at Peechi, said Kerala is becoming an experimental laboratory of climate change because of its sloppy terrains.
He cited the Intergovernmental Panel on Climate Change (IPCC) report on the Physical Basis of Climate Change, which was released in August this year, to buttress his point. “The IPCC report predicts rise in sea level and increase in rainfall. When we talk about floods in Kerala, we should pay attention to sea level rise,” he said.
Sajeev delved into the importance of understanding global predictions and translating them for local conditions. “In 2017, Kerala implemented a lot of drought management measures in Kerala. Rain pits were popularised. The forest department did gully plugging (to stop water from going out of the forest). At that time, we ignored warnings of intense rains. So all the efforts to manage drought were backfired. Water percolated to the ground through rain pits and serious situations emerged,” he said.
The discussion also delves into reasons for the formation of more cyclones in the Arabian Sea, how Kerala escaped many climate disasters, relevance of Gadgil Committee report on Western Ghats and the importance of taking scientists on board in the decision-making processes.
