This year’s southwest monsoon has been a monsoon of contrasts. It has been uneven across time and space, weak in many districts, and extreme in short bursts elsewhere. June ended with all-India rainfall at 40% below normal. A few intense spells in July and August narrowed the seasonal deficit sharply. But by late August, all-India rainfall was still about 14% below normal.

That all-India figure masks much sharper regional deficits. In fact, states such as Bihar and Andhra Pradesh are facing deficits of around 40%. This means that large parts of India can remain rain-deficient even when a few regions receive extreme rain. A seasonal deficit and a local flood can happen in the same monsoon, even in the same week.

Also Read | World heritage in the age of climate crisis

A super El Niño is evolving rapidly and could become the strongest we have recorded, adding further to this risk. An El Niño generally weakens the monsoon winds and increases the chance of below-normal rainfall. However, a weak monsoon does not mean weak weather risk. In a warming climate, the atmosphere and oceans carry more heat and moisture. When conditions become favourable, this moisture is often released as intense rain over a short period.

Over the Western Ghats, some locations received more than 1,000 mm of rain in just two days. Umargam in Gujarat recorded 1,064 mm in 24 hours, the third-highest daily rainfall ever recorded in India. To put this in perspective, 1,000 mm of rain means 1,000 litres of water falling on every square metre. On a 100 m² roof, that is about 100,000 litres, or 10 large water tankers. If drains are blocked,........

© hindustantimes