#Ajayan
Kochi | Kerala finds itself in a curious predicament as the southwest monsoon retreats across the nation but lingers stubbornly over the State. Caught between seasons, Kerala awaits the arrival of the northeast monsoon in just another 10 days. Even before the southwest rains fade, forecasts suggest an 'above normal' downpour in the upcoming October-December northeast monsoon season, an unpredictable close to the year.
During the official southwest monsoon season, Kerala had 16 per cent less rainfall than the seasonal normal. However, by the India Meteorological Department (IMD) standards, rainfall deviations between -19 per cent and +19 per cent are still classified as ‘normal.’ From June 1 to September 30, Kerala received an average of 1,718.8 mm, when the expected normal was 2,049.2 mm.
With the haunting memory of Wayanad’s landslide and the floods that swept across Kerala still fresh, the looming threat of an ‘above normal’ downpour during the upcoming northeast monsoon – Thulavarsham - casts a long shadow. Fears abound that this next phase of rains may bring more turmoil to the rain-battered State. According to the IMD, southeastern peninsular India is poised to receive 112 per cent of the usual October-December rainfall, surpassing the average of 334.13 mm. This climatic twist is attributed to the La Nina phenomenon, marked by unusually cold ocean temperatures in the equatorial Pacific, a stark contrast to the warming waters of El Nino.
Climatologists observe that this year's weather, marked by frequent lightning and thunderstorms coupled with heavy downpours, has been shaped by the relentless formation of low-pressure systems which is continuing and staggering the withdrawal of the southwest monsoon. October has so far seen thunder and lightning that are a feature of pre-monsoon showers or northeast monsoon.
Experts say La Nina often suppresses the northeast monsoon across the country, shifting its focus to the Southern Peninsular. Yet, they note that the Indian Ocean Dipole - the counterpart to the Pacific's El Niño Southern Oscillation - will likely remain in a neutral lull during the coming weeks. This delicate balance leaves the fate of the northeast monsoon in the hands of intra-seasonal developments.
The Indian Ocean Dipole, also called the Indian Nino, is an irregular oscillation of sea surface temperatures in which the western Indian Ocean becomes alternately warmer (positive) and then colder (negative) than the eastern part of the ocean. It is an oscillation of sea-surface temperatures between positive, neutral and negative phases.
