INCOIS revises outlook, forecasts ‘La Niña’ from September

INCOIS predicts high probability of La Niña weather condition in Pacific Ocean from September, which will peak in November.

INCOIS – Indian National Centre for Ocean Information Services, has revised the outlook for the probability of ‘La Nina’ weather condition in Pacific Ocean stating that its evolution is significantly highfromSeptember with a possibility to peak in November and its influence may continue till December with a probability as high as 70%.

La Niña, which usually aids rains in monsoon’, which usually aids the rains in the monsoon, is characterised with unusually cold ocean temperatures in the Equatorial Pacific, compared to El Niño, which is characterized by unusually warm ocean temperatures in the Equatorial Pacific.

The agency, under the Ministry of Earth Sciences (MoES), had last month has stated in its bulletin that the probability of development of La Niña was high in July-September (70-90%), and its continuation until February 2025 (50-70%).

In the latest bulletin, INCOIS with the help of its deep learning-based ‘Bayesian Convolutional Neural Network (BCNN)‘ model to have probabilistic outlooks of the future evolution of El Niño, said the sea surface temperature anomaly signature in the eastern and Central Pacific Ocean showed the near neutral conditions till August and September. Similarly, the development of La Niña is said to be high in September to January (50-70%) with a possibility to peak in November (70%). The probability for La Niña conditions to retreat is also high by February 2025 (55%), said scientists.

There was a prevailing El Niño condition in the Pacific Ocean until March/April 2024 followed by the neutral conditions. Subsequently, a subsurface negative temperature anomaly is seen in the entire equatorial Pacific by June 2024 giving indication of the development of La Niña conditions in the subsequent season.

INCOIS scientists pointed out that a prevailing El Niño condition in the Pacific Ocean has an adverse effect on the Indian summer monsoon rainfall and, thereby on the economic well being of the country. It is found to be causing stronger and prolonged marine heatwaves in the northern Indian Ocean, damaging the ecological balance, coral reefs and causing significant losses to the fishery industry.

Hence, monitoring El Niño condition and predicting its further evolution with sufficient lead time is of prime importance for better preparedness and policymaking, they added.