At the halfway mark, the southwest monsoon is precariously poised with large variations in spatiotemporal distribution across the country. Rainfall spread has been inequitable in the four homogenous regions. While at least 11 meteorological sub-divisions have a rain deficit of 30%-40%, the central and peninsular regions have received above-normal rainfall.
Rains have been inadequate over Uttar Pradesh, Bihar, Jharkhand, West Bengal, Punjab, Haryana and Chandigarh. Except for Sikkim and Sub Himalayan West Bengal, the monsoon rains have been sub-par in the northeast region. The shortfall has been 32% over Nagaland, Manipur, Mizoram and Tripura and below normal by 18% over Arunachal Pradesh. Parched conditions in June over north and eastern parts and flooding rains in July over Maharashtra and Gujarat have resulted lop lop-sided distribution, halfway through the season. The Perpetual rain deficit in the rice-growing bowl of the country has stressed the farmers and government, alike. Excess rainfall in July has hurt the prospects of coffee crops in the south and unfavourable weather conditions in the growing regions have hit the tea sector adversely in the north.
The paucity of monsoon weather systems in June and their unusual track through the central parts in July has ensued skewed rainfall distribution in the plains of north and central India. A series of low-pressure and cyclonic circulations have moved across the monsoon rainfed zone of Maharashtra, Madhya Pradesh and Gujarat. Resultantly, it has relieved these parts from the scare of any perennial drought, as observed repeatedly in the past. The surplus of about 10% rainfall over the country in July has compensated for the deficit of 11% rainfall in June. The seasonal rainfall, halfway through is very close to the ‘break-even’ point. The Pan-India rainfall stands at 454mm against the normal of 446mm, a mere 8 mm above the average.
Indian monsoon is largely controlled by the oceanic conditions, in the far Pacific and closer home, the Indian Ocean. The much-awaited La Nina, earlier expected during the monsoon, has been delayed. ENSO neutrality, as observed in the past, lasts for a few months. Accordingly, weak La Nina may arrive at the fag end of September or October. Even when it arrives, there is an inherent lag in realizing its impact. The Indian Ocean Dipole (IOD), has also defied the earlier prediction of turning positive during monsoon. The index anomaly is persistently negative, albeit within the neutral threshold. In any case, the model accuracy is also low beyond a few weeks, at this time of the year. It may be construed, that both the oceanic parameters, La Nina and IOD, may not offer any outright support to the monsoon 2024, during the second half of the season. Notwithstanding, the southwest monsoon, the largest global system of planet Earth, has enough intrinsic energy to propel a satisfactory normal season against all odds.
Image Credit: ABP live
