Private forecaster Skymet Weather will not release its monsoon long-range forecast this year since it wants to reflect on how an unusually strong positive Indian Ocean Dipole (IOD) last year evaded its radar.

“It’s a strategic call from our side,” Jatin Singh, Managing Director, Skymet Weather, told BusinessLine . “Last year, we completely missed the IOD. So there are certain patterns that we want to cross check. We will come back with our forecasts next year.”

Skymet is trying some new things. “We’ve done some algorithms, we’ve done some output. We want to do something radically different. Last year, the strong IOD had come out of nowhere. And it turned the tables on patterns that we’ve been witnessing before,” Singh said.

Till July 2019, the monsoon was -19 per cent. Chennai had reached day-zero for its water supply. And then came the floods. If one looks at model outputs across the globe, none had any inking of it.

As for the Equatorial Pacific conditions (El Nino-La Nina), they were the preponderant factor nine out of 10 times, even if there was a minor disturbance. But not last year, Singh said.

Forecast complexity

“We just want to reflect back on the 100-year-long relationships. We’ve added some computing power but frankly speaking, computing power can be very misleading. It's a redundant obsession, if you will. The dynamics of the monsoon are only partially understood. The statistical correlation tends to be more durable . If the dynamic models were so good why is it that nobody got the IOD or even the monsoon forecast right?

“The best that we could’ve figured out last year was that it would be IOD-positive and therefore a better monsoon year than earlier thought. If the IOD had been neutral or slightly positive and the Pacific behaved the way it did last year, it would’ve been a below-normal year and we probably risked a drought. But the powerful IOD that flipped everything over does not jell with the scheme of things,” Singh said.

 

“The Pacific factor has been quite unstable during the last couple of years. After the 2014-2015-2016-2017 cycle, some things have not been working as they did in the past. We will try to get a handle on it and it will keep us busy through the year,” he added.