The India Meteorological Department (IMD), while forecasting a ‘normal’ southwest monsoon for this year also, revised downwards the definition of what constitutes average rainfall.
At a press briefing on Thursday, the agency said India would get 99% of the long period average (LPA) rainfall — changed from 89 cm to 88 cm in 2018, and in the periodic update in 2022, again revised to 87 cm.
A monsoon is considered “normal” when rainfall falls between 96% and 104% of the LPA.
The IMD does not expect an El Nino, a phenomenon associated with a warming of the Central Pacific and drying up of the rains over northwest India, the coming monsoon. “Currently La Nina conditions are prevailing over equatorial Pacific. The latest forecasts indicates it will continue during the monsoon,” the IMD stated.
Current indications suggest “normal” to “above normal” rainfall in the northern parts of peninsular India, central India and the Himalayan foothills. Many parts of northeast India and southern parts of South India are expected to see a subdued monsoon.
The IMD does not expect an El Nino, a phenomenon associated with a warming of the Central Pacific and drying up of the rains over northwest India, the coming monsoon.
“Currently La Nina conditions are prevailing over equatorial Pacific. The latest forecasts indicates it will continue during the monsoon,” the weather body said.
The IMD’s April forecast doesn’t indicate if some monsoon months will experience below normal rain or regional variations. This information is expected by the end of May.
Weather station data historically used to be delayed but now the IMD had moved to an automated system that provides real-time data from close to 4,000 stations compared with the 1,000-odd stations from even a decade ago.
On Tuesday, private weather forecasting agency Skymet, too, forecast monsoon 2022 to be ‘normal’, adding that rainfall in August will likely be subdued.
Among the consequences of climate change are alterations to the monsoon. There are increased stretches of dry spells followed by spells of intense rain.
However, officials say that while the monsoon patterns are affected, monsoon rains are expected to increase over the next decade.
“External forces impact the monsoon and these are being studied. But the 30-year pattern is expected to hold and the next revision might see an increase in the decadal average,” said M. Ravichandran, Secretary, Ministry of Earth Sciences.
As part of its update, the IMD said that annual rainfall had decreased to 116 cm from 117.6 cm. The southwest monsoon contributes about 75% of India’s total rainfall with June (19%), July (32.3%), August (29.4%) and September contributing 19.3%, respectively.
Published - April 14, 2022 03:40 pm IST
