BY PAUL FERNANDES
In a remarkable year that saw the mercury swing both ways and the rain graph showing identical behaviour, the month that just ended also turned out to be anomalous, as IMD, Panjim, recorded the lowest August rainfall in several decades.
With long spells of dry conditions after a deluge in July, sparse rainfall of just 289.4 mm was recorded during the entire month, while 710 mm is considered normal.
The seasonal total, despite the poor rainfall in August, is inching towards normal, as the India Meteorological Department, Panjim, has recorded 2776.8 mm so far as compared to the normal value of 2487.4 mm, at this stage.
This has been possible mainly due to the extremely heavy rainfall of 1836.2 mm recorded during July this season. This made July the wettest month for more than seven decades and produced a surplus of 75.4%.
The copious rainfall also threw up an overall surplus of 26.8% and also sponged off a deficit of 28% in June this year.
This year has been quite unusual. The month of January had more nip in the air, ending as the coldest first month in five years. Later, February and March were the hottest months respectively in decades.
This year there was a probability of El Niño in the Eastern Equatorial Pacific Ocean, which coincides with the peak monsoon period of July and August. Usually, the monsoon peaks during these two months, contributing about 70% of the seasonal totalM R Ramesh Kumar, Meteorologist and Former Scientist at the National Institute of India
Anomalously poor pre-monsoon rainfall, delayed monsoon onset and weak rainfall activity in June disrupted farming operations and caused other problems.
Meteorologists have been watching these severe weather events and attribute them to climate change factors.
“This year there was a probability of El Niño in the Eastern Equatorial Pacific Ocean, which coincides with the peak monsoon period of July and August. Usually, the monsoon peaks during these two months, contributing about 70% of the seasonal total,” M R Ramesh Kumar, a reputed meteorologist and former scientist at the National Institute of India (NIO), said.
This year, dry conditions have prevailed for extended periods. “Monsoon advanced over Kerala on June 8 and over Goa on June 11 and an unusually extreme cyclonic event in the form of Cyclone Biparjoy reduced moisture availability for the monsoon in June,” Kumar said.
The monsoon then progressed and covered the entire Indian subcontinent by July 2, well ahead of the normal arrival by July 8 in the northwestern part of India.
Another interesting feature was that Gujarat and Rajasthan received rainfall well ahead of the monsoon onset over these two sub-divisions.
The southwest monsoon became inactive and no strong synoptic systems formed for long periods. It was light or moderate rain in isolated places, and heavy only at very few centres in the state during the month.
Monsoon activity has been weakening during the third of the four-month season in recent years, producing below-normal rainfall. At this stage, regular showers are crucial for the state’s paddy crop.
For three weeks in August, IMD, Panjim, recorded hardly 100 mm of rainfall, whereas the highest 24-hour rainfall was 142 mm on June 28.
It was a cyclonic circulation in the Bay of Bengal that moved inland and triggered some rainfall activity. It produced 90+mm of rainfall on two consecutive days, August 25 and 26, and provided some relief from sultry conditions.
Monsoon activity has been weakening during the third of the four-month season in recent years, producing below-normal rainfall. At this stage, regular showers are crucial for the state’s paddy crop.
As per this trend, the rainfall recorded during August was 367 mm in 2021, 369 mm in 2022 August while the lowest for some time was 322.9 mm in 2009.
The other figures of lower-than-normal in August are 532.1 mm in 2013, 510.7 mm in 2015, 487.4 mm in 2016 and 502.8 mm in 2017. In 2014, there was very heavy rainfall of 1062.6 mm.