The countdown for the Southwest Monsoon season starts much before its commencement in June. The oceanic parameters many a time play foul and hold the monsoon to a literal ransom. Of all these sailing indices, the most dreaded El Nino scares the most and leaves anxious moments although the season. The good news is that El Nino is resting this season and the ‘Monsoon’ is going to run with its own steam.
Historically speaking, El Nino and La Nina events tend to develop during the period April-June and tend to reach their maximum strength during October-February. Typically, these episodes last for 9-12 months, though occasionally persist even for 2 years. El Nino in general has a periodicity of occurrence once in 2-7 years. It is of more critical concern for India, as the country is largely dependent on monsoon rains for its main crop season ‘Kharif’.
Pacific Oceanic conditions are out of the ‘spring barrier’ now and can be relied upon with a large degree of confidence. East and Central Pacific, hosting the NINO indices, after remaining warm for 8 months in a row is now inclined towards cooling and suggesting neutral but below the average Sea Surface Temperature all through the Indian Summer Monsoon Rains (ISMR). Possibly the conditions are slipping towards a weak La Nina territory through fall of the season. The probability of El Nino is less than 10% and the season commences with towering neutral conditions with a probability of over 70%. The La Nina probability starting with 20% grows at the behest of neutral to reach nearly 50% by end of the season.
All the four Nino indices measured in the East and Central Pacific have dropped below zero (</=) and are increasingly negative in the eastern section. Nino 3.4 index directly linked as a measure of El Nino/ La Nina has dropped below the threshold neutral of -0.5 after 26 months (02 April 2018: -0.7). Below-average temperatures are likely to be retained in all the four sections during the summer monsoon.
Indian Monsoon 2020 seems to be safe from the clutches of El Nino. But there does not seem to be any support from the Indian Ocean Dipole (IOD) which swayed the Monsoon 2019. Monsoon has its own dynamics and energy to generate the monsoon systems in the Indian Seas. The frequency, track, and intensity of these systems are the ultimate decider of the fate of monsoon.
