<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/in-farmer_1.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/in-farmer_1.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/in-farmer_1.jpg?v=ap&w=980&h=551 800w" > Representational image of a farmer looking up to the sky from his parched field in Bihar. (K M Sharma / BCCL, Patna)

At a Glance The formation of El Niño has officially been confirmed by the American scientific agency NOAA.

El Niño is often associated with a lower-than-normal rainfall for India.

The expected strength of El Niño is ‘weak’, and hence widespread global impacts are not anticipated. The formation of El Niño—often called the 'bad boy' of global weather—has officially been confirmed by National Oceanic and Atmospheric Administration (NOAA), an American scientific agency. However, many experts believe that the late formation and the weak strength of this year’s El Niño may not have any significant impact on global weather patterns. Therefore, only time will tell its impact on the 2019 summer monsoon in India.

The official declaration from the Climate Prediction Center, a part of the NOAA, came on Thursday as an advisory that stated: “weak El Niño conditions are present and are expected to continue through the northern hemisphere spring 2019”. Spring in the Earth's northern hemisphere, as per the meteorological calendar, refers to the months of March, April and May.

What does this mean for India?

Dr Todd Crawford, Chief Meteorologist at The Weather Company, indicated a possible dry start to the monsoon earlier this month. Overall, he suggested that the early forecasts skew slightly towards a drier monsoon with 95% of normal rainfall. However, he warned that it is still too early to arrive at any certain conclusion.

Meteorologists have deliberated upon this year’s El Niño for over ten months now. The latest reports even suggested that many experts had given up on the possibility of El Niño formation, raising the hopes for a good monsoon this year. However, the current advisory from NOAA has raised concerns of water deficits and droughts yet again. In addition, the formation of El Niño can make 2019 one of the hottest years on record and accentuate the threats of heatwaves.

A silver lining is that the expected strength of El Niño is ‘weak’, and hence widespread or significant global impacts are not anticipated. The NOAA forecast adds that the predicted chance of El Niño persisting beyond May is 50% or less. Therefore, in case a transition happens towards La Niña conditions during the second half of the year, as expected by some meteorologists, a drier June may be followed by a much wetter July and August.

What happens during El Niño?

In normal (neutral El Niño South Oscillation or ENSO) conditions, the to trade winds from east pool the warm water in the western Pacific Ocean region near Australia and Indonesia. As the warmer water drives deep atmospheric convection, extensive rainfall happens around Indonesia during the months of June-August. In short, the warmer water brings rains with it.

During El Niño (positive ENSO conditions), the trade winds weaken or reverse and the area of warmer water spreads in the central and eastern Pacific towards South America. As the warmer water spreads, the rains and the thunderstorms also move away from the Indonesian region.

The monsoon winds are primarily drawn towards Indian landmass due to the difference in heat. El Niño dampens the conditions that are needed for attracting the moist monsoon winds towards India and affects the frequency of monsoon low pressure systems. Therefore, El Niño is often associated with lower-than-normal rainfall for India.

Meteorologists across the world always keep an eye on the sea-surface temperatures (SSTs) at the equatorial Pacific Ocean for the formation of El Niño conditions, as this phenomenon has a major impact on weather patterns across the globe. El Niño occurs at irregular intervals approximately every 2-7 years. The last El Niño episode was in 2015, which was a year of extensive drought across India.

The Weather Channel will keep close watch on the progress of El Niño and analyse its impact on India; so keep checking back for updates!