The southwest monsoon is likely to remain “below normal” or “deficient” from June to September this year due to the development of El Nino. Weather forecaster Skymet has predicted monsoon to be 93 per cent of the long-term average (LPA) due to El Nino phenomenon.
This is in contrast to the February reports by Skymet and IMD, according to which monsoon rains in India were expected to be normal this year.
According to Skymet, there is a 55 per cent chance of a “below normal” rainfall. The forecast has a 5 per cent margin of error, said Skymet. The weather forecaster said there is 55 per cent chance of a below-normal monsoon, 30 per cent of normal rains and a 15 per cent chance of a drought.
“The Pacific Ocean has become strongly warmer than average. The model projections call for an 80 per cent chance of El Nino during March-May, dropping to 60 per cent for June to August,” Skymet said.
Deficient monsoon is likely to dent farm prospects and the economic growth in the country as approximately half of the country’s arable land lacks irrigation facilities.
Kharif crops like rice, cane, corn, cotton and soybean are produced during the monsoon season.
Anything between 90-95 per cent of long-term average falls under the "below normal" category. Monsoon is considered normal when LPA is between 96 per cent and 104 per cent. LPA is the average of rainfall between 1951 and 2000, which is 89 cm.
The southwest monsoon arrives on the southern tip of Kerala around June 1 and retreat from Rajasthan by September.
El Nino brings suppressed rainfalls in India, while its opposite is La Nina, which brings good showers. This is important because 13 of the last 20 droughts in India occurred during an El Nino. Skymet has also not completely ruled out the possibility of a drought.
Meanwhile confusion prevails over the development of El Nino weather pattern as the Australian Bureau of Meteorology has retained its 'El Nino alert', signalling an approximately 70 per cent chance for the warming event to occur in the East Equatorial Pacific while the US's Climate Prediction Centre predicted that El Nino conditions are likely to continue through spring 2019 (80% chance) and summer (60% chance). The National Oceanic and Atmospheric Administration (NOAA) had put out a notification in February saying that 2019 would see an El Nino rising, albeit a moderate one. Back home, the India Meteorological Department (IMD) has assessed that the current weak El Nino conditions may persist until June.
A strong El Nino, marked by a warming of the sea surface on the Pacific Ocean, can cause severe drought in many regions like Australia, Southeast Asia and India, while drenching other parts of the world such as the US Midwest and Brazil.
"The Pacific Ocean has become strongly warmer than average. The model projections call for 80% chance of El Nino during March-May, dropping to 60% for June to August," said Jatin Singh, managing director of Skymet. This means, it is going to be a devolving El Nino year, though retaining threshold values all through the season. Thus, monsoon 2019 is likely to be below normal." The emergence of a strong El Nino triggered back-to-back droughts in 2014 and 2015.
"Eastern India is likely to be at a higher risk of getting deficient rain, especially during the first half of the monsoon season. Showers are expected to be 77 percent of the long-term average in June, 91 percent in July, 102 percent in August and 99 percent in September," the Skymet said.