Author(s): Shadananan Nair
Linked Author(s):
Keywords: Extremes; Kerala; Flood; Socio-economic; Policy; Adaptation
Abstract: Abnormal and unexpected extreme rainfall associated with climate change creates devastating floods in the thickly populated tropical State of Kerala in India. Seasonality and intensity of rainfall are increasing and tropical storms are becoming more severe. In August 2018, exceptionally high monsoon rains lead to the worst flooding in a century, killing around 500 people and thousands of livestock, displacing one million people and damaging 50000 houses, roads and other infrastructures. Estimated losses amount to more than US $3 billion. Seasonal rainfall was 42% above normal and rainfall during 1 to 19 August was 164% above normal. Around 414 mm rainfall occurred during August 15-17, which led to severe flooding. Steep slopes and destruction of wetlands added to its severity. All 39 major dams had reached their full reservoir level by the end of July, and were incapable of absorbing the torrential volumes in August. After flood, surface water bodies, especially rivers dried up fast because of abnormal landslides and sedimentation. Around 8 to 10% of all reservoirs were already filled with sand because of deforestation and urbanization. As a result of the loss of surface soil and failure of northeast monsoon, groundwater level in the state fell by 3 metres and the State experienced serious water crisis in the beginning of 2019 itself. Destruction of check dams and erosion and deepening of rivers allowed fast flow of groundwater towards the sea. Decrease in runoff permitted salinity intrusion far inland. Again in August 2019 the rainfall became abnormal, leading to flood, but the severity was less compared to 2018. The trend is continuing and Kerala expects flood hazard during every monsoons. Kerala is facing the combined effects of climate change, population pressure and unscientific land utilization. A meteorological unpredictability is looming large over the area. State is not prepared to cope with the unexpected situation and flood initiate several socio-economic issues such as shortage of reliable water, hiking price of food and water, conflicts over allocation, spread of contagious diseases and large investment to rebuild infrastructure and rehabilitate the displaced population. This study analyses the hydrometeorological extremes in Kerala and their impacts on different facets of life. State needs a better prediction system and strategy for adaptation, impact mitigation and risk reduction. . Guidelines for developing a better climate policy and adaptation and mitigation strategies have been provided.
Year: 2024