Monsoon and Climate shift cause devastating flooding in India

Climate change has had extreme impacts in India. Rise in average global temperatures have led to a worrying trend of no rain for long periods and then a sudden bout of excessive rainfall, causing extreme weather events, particularly floods which took lives, destroyed homes and agricultural yields as well as resulted in huge revenue losses.  The resulting floods are being exacerbated by unplanned urban growth and environmental degradation, driving millions from their homes and causing widespread damage.

For centuries, Indians have rejoiced at the arrival of the monsoon to break summer’s fever. This year, India’s monsoon season has overrun by almost a month, with unprecedented rainfall causing deaths from collapsing buildings and many crops beginning to rot. Normally the monsoon in north India recedes by the beginning of September, but the average rainfall this month has been 37% above normal. If the situation continues for the remaining few days, it will be the latest the monsoon has ever receded in decades, according to experts in the India Meteorological Department.

The torrential rains that submerged parts of India this year are the latest in a string of major floods in the past decade, some caused by record rainfall - a scenario that many fears could become the “new normal” as climate change increases the frequency of extreme weather. This year, the monsoon arrived late with fierce intensity, where spells of heavy rain have led to flooding in 11 states, taking 1200 lives and displacing millions. India’s summer monsoon has always been variable and has often precipitated floods, especially in the basins of the great Himalayan rivers. But experts say that a combination of global warming, unplanned urban growth, and environmental degradation is increasing flood risk in India.
 
New studies show that extreme precipitation events are on the rise in large parts of India, especially multi-day deluges that lead to large-scale floods. Warmer temperatures are also speeding up glacier melt in the Himalayas, which is projected to increase flow rates in the Ganges and Brahmaputra Rivers. Last year’s historical floods in the southern state of Kerala were due to the destruction of mountains and hills, as well as development on floodplains and marshes which are exacerbating risks. These floods were caused by extreme rainfall and mismanagement of dam reservoirs, but mining and construction in the Western Ghats, a major hill range, contributed to damaging landslides. The floods in August 2018 took 483 lives, affecting 5.4 million people, and temporarily shut down the state’s new airport, which was built on a floodplain.
 
One key to preventing or reducing flood damage is understating the shifting contours of the summer monsoon, which brings about 35 inches of rainfall to India every summer. A complex weather system influenced by both global atmospheric circulation and regional meteorological forces, the monsoon is an important piece of the climate puzzle- any change in the system affects the food and water security of billions in the Indian subcontinent, many of them extremely poor. 

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© 2019 Oceanographer Daneeja Mawren