Need to wait till April for clear picture on El Niño: KS Hosalikar, IMD

IMD yesterday in the summer forecast also indicated that they expect the effect of the El Niño current to come down. Could you quantify what is the indication when you say that it could come down?
No, it is not El Niño, it is La Niña which is weakening from October. We have a triple dip La Niña which is one of the unique case as far as the climatology is concerned. So we continuously had three years of La Niña which is favourable for the monsoon season for the India but from October onwards the La Niña conditions are weakening over the equatorial Pacific Ocean and the climate models are also suggesting that there is a possibility of development of El Niño also but there is a rider on this that the predictions made in the month of February or March for the ENSO conditions that is the equatorial Pacific temperature SSTs are there.

The uncertainty is there and the skill is not much, we call it as a spring barrier, so we need to watch it and we will give better update for that in the month of April. The spring barrier is something that will prevent us from very accurate forecasting, it is a global issue.

Historically we have seen that when the El Niño effect has been there and I am looking at a UBS report which maps the last 30 years where three times the El Niño impact has been there, it has had an impact on the monsoon distribution. So can I say that this year we could be in for a bad monsoon or a poor monsoon or there could be a challenge with the monsoon distribution?
Yes, this is a good question, I will answer it in two parts. First is I have a data with me from 1951 to 2022 and it is almost like more than 70 years old data and there were about 16 cases when El Niño was there and out of that 16 cases there were nine cases when it affected the Indian summer monsoon. So what it indicates that every time when the El Niño is there the Indian summer monsoon did not get affected, this is number one. So that fear of one to one, El Niño is there and the monsoon is going to get bad, I think we need to have more clarity on this.

Number two, the monsoon depends not only on El Niño but it also depends upon many other factors like Indian Ocean, dipole in the Indian Ocean, the Eurasian snow cover and because we are in the tropical country the local weather also affects during the monsoon season. So there are various other factors on which the performance of the monsoon depends. Now coming to whether this will be a bad monsoon or this will be a good monsoon, I would suggest and the Metrological Department said it very clearly that we have to wait because the current ENSO predictions are having the trouble of the spring barrier that is at this time of the year when we talk about the El Niño predictions or ENSO prediction, the intrinsic uncertainties are there because of the low coupling of the ocean and atmospheric over the equatorial Pacific. So we have to wait for some more time for having more clarity whether the El Niño would be there or at what time it would be there. Currently it is suggesting that it would be at the end of the monsoon season but we need to wait for more clear picture on El Niño.

When we have seen this kind of an El Niño current in the month of February and March, what has been the divergence? How much the divergence has been there in terms of the initial assessment versus what actually is the final outcome?
Yes, even the current predictions are also indicating that La Niña conditions are becoming or the ENSO conditions are becoming neutral in the summer monsoon that is during this March, April and May. Later on I think it is going to have some effect on development of El Niño. There are years like 2012 I remember like this the predictions were there but then there was no impact of that. So it all depends upon not only the El Niño but it depends upon at what time its peak would be there whether we will see during the summer or later part of the monsoon.
These are the things which will also have lot of impact on the summer monsoon and it is not one to one that is very important.

Just want to understand when it comes to summer if you could reiterate for us is there a high probability of the occurrence of a heat wave during the months of March to May? How bad could it get for some of the states like Rajasthan for places like New Delhi etc.?
Yes, we in the month of February have seen a lot of temperature rises in the part of northwest of India Konkan, centre part of the India that is including Maharashtra. We saw temperature soaring up to 37 to 39 degrees centigrade at many places in the beginning of February. Yes, later on it got stabilised. The prediction for the March, April and May that we have said that yes there is a good possibility that the heat waves could be possible in March, April and May. We have also yesterday submitted what could be the heat wave scenario in March. March is not indicating that number of heat waves as compared to the rest of the season like March, April and May. So what is expected probably is that the season could pick up with the more number of heat waves in the month of April and May. Of course; monthly, weekly and daily predictions also could be available during the course of time.

Is it all about global warming the most talked about debate, I mean are weather patterns changing because of global warming?
Yes, I think now if you see the February temperature it just gives you a glimpse of it. The average February temperature at all India level was about 29.5 degree centigrade that is the highest temperature in the February for last 122 years for all India level. So February literally remained very warm at all India level. Even the minimum temperature remained warmer at number six for last 122 years of data as the whole country. So let us accept it that we are living in a warming environment and yes the climate predictions are also stating that line only that the temperatures are going to rise. Yes, in 2022 March I remember, there were extraordinary heat waves especially in the northern part of the country. In northwest Rajasthan even Gujarat also had a number of heat waves. Temperatures were above 40 at many places. But this year we are expecting that March would not be that harsh but maybe April and May we need to keep watch on the heat waves and the rise in the temperature.