El Nino develops, experts wary of poor monsoon spell
Weak El Nino conditions emerged in May over the equatorial Pacific Ocean with above average sea surface temperatures (SSTs)
El Nino conditions have emerged, the National Oceanic and Atmospheric Administration said on Thursday, with the weather phenomenon threatening to push the global temperature to new highs.
Read here: Monsoon finally reaches Kerala, but onset weak
Weak El Nino conditions emerged in May over the equatorial Pacific Ocean with above average sea surface temperatures (SSTs). These temperatures sustained up to June with wind parameters supporting the emergence of El Nino, the NOAA said in its El Nino Southern Oscillation (ENSO) bulletin.
“We expect El Niño to continue into the winter, and the odds of it becoming a strong event at its peak are pretty good, at 56%. Chances of at least a moderate event are about 84%,” the NOAA bulletin said.
El Nino is the warming of waters in the Eastern Pacific Ocean, often accompanied by a slowing or reversal of easterly trade winds. The phenomenon creates a cascade of weather effects across the world — in India, this leads to the monsoon being drier than usual.
“El Niño — the warm phase of the El Niño-La Niña climate pattern — changes global atmospheric circulation in known ways, giving us an idea of potential upcoming weather and climate patterns. A stronger El Niño means global temperature, rain, and other patterns are more likely to reflect the expected El Niño impacts,” a blog by NOAA explaining the event said.
Global average sea surface temperatures have already touched record highs this summer. On June 6, the average SST was 20.9°C compared to 20.7°C last year, breaking past records.
For India, the NOAA announcement does not bode well, with experts warning that the government and farmers should prepare for impacts of El Nino.
“It was expected that El Nino would develop soon. The pacific warmed up so fast. It is going to be a severe El Niño. It is worrisome and the government should have a plan B for a below normal rainfall. June is going to be bad with monsoon delays. Farmers could be advised properly,” said M Rajeevan, former secretary, ministry of earth sciences.
El Nino onset during the current monsoon means a delayed onset and deficit rainfall, Roxy Mathew Koll, climate scientist at Indian Institute of Tropical Meteorology (IITM) had told HT in an interview on June 5.
“Usually, an El Niño starts brewing in the Pacific during summer and reaches peak intensity by winter. This year, global models are expecting the El Niño to be in place by June itself. El Niño events interact with the global atmospheric circulation and trade winds. The monsoon winds are also part of this large trade wind system. During El Niño events, the monsoon winds are slow to pick up, and are relative weak. An El Niño during the current monsoon season hence means a delayed onset and deficit rainfall. Forecasts from the India Meteorological Department (IMD) already indicates dry conditions over northwest and central India,” Koll said.
The delayed onset is also expected to push the window for sowing of crops, GV Ramanjaneyulu, Executive Director at Centre for Sustainable Agriculture, said.
“IMD is predicting a normal monsoon which may be normal for the season as a whole but its critical to know if there will be gaps during the season and well distributed. We expect dry spells in July and August, that’s when most crop losses happen. Rainfed crops dry up. So, first, we have to shift to pulses oilseeds not water intensive ones to adapt better; second, critical irrigation during monsoon gaps tailored for life saving irrigation during dry periods; and third, if there is residual risk then we need proper insurance mechanism which is not available,” said Ramanjaneyulu.
Koll, meanwhile, also warned of extreme weather events. “Events like an El Niño can sometimes amplify the climate change impacts,” he said.
“If this is a strong El Nino as predicted by global models, then this year could be one of the warmest years,” Koll said.
On May 17, the World Meteorological Organisation said there is a 66% likelihood that annual global surface temperature will temporarily exceed 1.5°C above pre-industrial levels for at least one of the next five years, with El Nino and climate crisis fueling the temperature rise and Arctic heating.
Read here: Monsoon arrives in Kerala after 7-day delay; progress to be slow in 1st week
The last time an El Nino was in place, in 2016, the world saw its hottest year on record.
NOAA calls an El Nino when ocean temperatures in the eastern and central equatorial Pacific, have been 0.5°Celsius higher than normal for the preceding month, and has lasted or is expected to continue for another five consecutive, overlapping three-month periods. The agency also looks at a weakening of the trade winds and cloud cover.
