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El Nino may be 'neutral', normal rains likely this year

March 23, 2020 08:00 IST

The latest IMD forecasts show that sea surface temperatures might further cool, enhancing the probability of La Niña after July.

Amid the gloom, there is some good news on the weather front.

The latest forecasts show that the dreaded El Niño weather phenomenon, known to disrupt the flow of the southwest monsoon, is expected to remain ‘neutral’ in May, June and July.

 

The latest India Meteorological Department (IMD) forecasts show that sea surface temperatures might further cool, enhancing the probability of La Niña after July.

These weather phenomena indicate that the monsoon may be normal in India this year.

The southwest monsoon enters India in June and starts withdrawing in September.

July is the critical month as the quantum of rains is highest then.

A good monsoon is crucial for Indian agriculture and the economy in general as less than half of India’s farmland is irrigated.

The El Niño is defined as an increase of Eastern Tropical Pacific’s sea surface temperature (SST) of 0.5 degree Celsius from long-term average, while its opposite, the La Niña, is defined as a decrease of SST over the same area by -0.5 degree Celsius from the average.

El Niño plays a big role in the performance of India’s southwest monsoon.

Data studied by private weather forecasting agency Skymet shows that in the 135 years starting 1880, about 90 per cent of all evolving El Niño years led to below normal rainfall, while 65 per cent of evolving El Niño years saw droughts.

“During an El Niño year, the rainfall is generally below the normal average, which has its negative bearing on crop production,” the Skymet report had said.

If that’s not all, the Indian Ocean Dipole (IOD), another factor that has a bearing on the southwest monsoon’s performance, is also expected to remain neutral during most of the forecasted period, according to IMD.

All these factors provide hope that unless there is a dramatic change in conditions, initial indications show that the southwest monsoon might be normal in 2020.

“So far, we haven’t noticed any major adverse conditions as far as southwest monsoon in 2020 is concerned, but much of it will get clearer after middle of April,” a senior IMD official said.

Weathermen though warn that it is still early days and predictability of El Niño is limited.

Photograph: Reuters

Sanjeeb Mukherjee in New Delhi
Source: source image