Why has monsoon wreaked havoc so early this year?

The month of June is not over yet, but monsoon has already covered most parts of India. This usually happens by mid-July. Many cities are witnessing heavy rainfall. The Indian Meteorological Department (IMD) issued a yellow alert for Delhi on Tuesday. Assam has been witnessing floods. There’s cloudburst-like situation in Himachal Pradesh and Uttarakhand. Flash floods and landslides have taken many lives here. It's only June and monsoon has already wreaked havoc in so many states. Why? Monsoon arrived at super speed in northwest India. It was held up over east India for a long time, but when it started moving, it moved with gusto. Within four to five days, it had covered almost the entire central India and most of northwest India. This happened because the conditions were conducive for monsoon rainfall. Monsoon was in an active phase. At this time, usually the hills of northwest Indian states such as Himachal Pradesh, Jammu & Kashmir and Uttarakhand tend to get a lot of rains. This is what happened in Himachal Pradesh. Monsoon was delayed in Kerala by a week, but it arrived early in Delhi. Why? Monsoon was held up because of the formation of Cyclone Biparjoy over the Arabian Sea. When a system as big as a cyclone forms over the sea, it draws moisture towards itself. Monsoon is a giant sea wind that enters the land. During this time of the year, monsoon winds arise from the Indian Ocean, take a curve and come into India. One arm of the monsoon system comes through the Arabian Sea and the other through the Bay of Bengal. It hits the eastern coast and progresses towards northwest India, sweeping Central India. With cyclone forming over the Arabian Sea, that process got delayed. The cyclone started moving northward taking moisture away from places where the monsoon winds would have reached in normal course. As a result, the progress of monsoon got stalled. Cyclone Biparjoy hit the Gujarat coast and made its way via Saurashtra towards Rajasthan, north Madhya Pradesh, and finally it ended in Uttar Pradesh where it remained active for three to four days. Once Biparjoy was over, it attracted the Bay of Bengal arm of monsoon. That’s when monsoon progressed rapidly over northwest India and arrived in Delhi on June 25, two days ahead of schedule. By this time, monsoon had got active and invigorated because of another system forming in the Bay of Bengal. Monsoon progressed to Mumbai where it was 14 days behind schedule. As a result, we had an unusual spectacle of the monsoon arriving in Delhi and Mumbai on the same day. Can El Nino, forming over the Pacific Ocean, impact monsoon rains in India? Earlier this month, the US weather systems declared that El Nino had formed early in summer. It will slowly become stronger. Unfortunately for India, it overlaps with monsoon. This is not good news for monsoon rains. El Nino is an abnormal warming of the ocean waters over east and central Equatorial Pacific. That's a vast region and when such a vast region warms up, it leads to changes in wind currents. These changes ultimately affect the weather across the world. The Indian Meteorological Department expects the full impact of El Nino to be felt around late July till September. The presence of El Nino means the overall condition for monsoon rainfall in India will not be good. But this does not necessarily mean that India will get bad monsoon. There are other parameters that also affect rainfall in India, such as the conditions over the Indian Ocean, and a pulse of weather disturbance that moves across the equator called the Madden-Julian Oscillation (MJO). Sometimes these smaller factors outweigh the big overall conditions, which is dictated by El Nino. Sowing of kharif crop has not started yet. What is the outlook for the coming weeks on that front? Farmers were not sowing because monsoon had not arrived in most parts of India. Now, monsoon has covered more than 80 per cent of the country. The only places it has not reached yet are western Rajasthan, parts of Saurashtra and Kutch in Gujarat, some parts of western Haryana and Punjab. Most of this region, especially western Rajasthan, has already got a lot of rain because of Biparjoy. Sowing is expected to pick up now. In India, July is a crucial month for sowing of summer, or Kharif crop. Maximum sowing takes place in July. We have to wait and see how the monsoon fares in July. The next five days at least we will see good rainfall. Probably this good spell is going to last a little longer. The longer this spell of rain lasts, the more sowing you will see. Last year a UN report said heat waves may break human survivability limit in India this summer. Has that happened? In a warming world, average temperatures are rising because of climate change. In India as well, average temperatures have been rising for the past many decades, and pace has accelerated. All models say the intensity, frequency and intensity of heat waves will rise. This means it will cross human survivability limit at some places for a few days every season. This time, northwest Indian states such as Punjab, Haryana, Rajasthan did not see too many heat waves because Western Disturbances were active. These states got periodic rainfall through the summer season till the arrival of the monsoon. Indian witnessed mild summer this year, except for Eastern UP, Bihar, Jharkhand, spots of Chhattisgarh and Odisha. Eastern UP and Bihar witnessed several deaths due to heat waves. We need to be prepared for this scenario because this is going to be a regular occurrence every summer in India. The government needs to make people aware about the dangers of heat waves. Audio Production: Shantanu Nanoti