In a departure from the established four-year pattern of experiencing ‘normal’ or ‘above normal’ rainfall between 2019 and 2022, India’s monsoon season concluded with ‘below normal’ rainfall, accounting for 94.4% of the long-period average (LPA). This revelation is based on data released by the India Meteorological Department (IMD) for the period spanning from June to September, marking a significant shift from the preceding years.
Typically, rainfall ranging between 96-104% of the long-period average (LPA) is categorized as ‘normal.’ Despite the presence of El Nino conditions, which typically have an adverse impact on the monsoon due to the warming of sea surface temperatures in the central and eastern tropical Pacific Ocean, India’s monsoon season concluded with rainfall that was remarkably close to ‘normal.’
IMD Director General M. Mohapatra attributed this outcome to the mitigating influence of other meteorological factors, which lessened the impact of El Nino, thereby ensuring that the monsoon remained very close to the predicted ‘normal’ range.
While the IMD had initially forecast a ‘normal’ monsoon for the year, anticipating rainfall at 96% of the LPA with a margin of error of +/- 4%, an extensive deficit of 36% in August led to the overall monsoon rainfall registering at 94.4% of the LPA, which is based on data spanning from 1971 to 2020.
Analyzing the reasons behind the August deficit, Mohapatra mentioned that efforts have been initiated, involving academic and research institutions, to thoroughly investigate the matter.
Notably, historical data reveals that not all El Nino years result in poor monsoons. In fact, 40% of such years in the past witnessed normal to above-normal monsoon rainfall. Among the 15 El Nino years recorded between 1951 and 2022, six of them reported normal to above-normal rainfall. El Nino years are typically characterized by above-normal temperatures, suggesting that this year’s winter may not be exceptionally severe, although any predictions in this regard remain preliminary.
The IMD is expected to release a winter temperature outlook for December to February at a later date.
Despite a 9% rainfall deficit in June, the month largely adhered to predictions. In contrast, July and September proved favorable for the monsoon, with both months experiencing a 13% increase in rainfall. This favorable pattern significantly benefited the Kharif sowing operations, particularly in July, which marks the primary sowing season for Kharif crops. Consequently, Kharif sowing operations concluded with an acreage exceeding the average of the last five years and surpassing the sown area of the previous year.
The IMD’s comprehensive season-end report further delineates the distribution of rainfall across meteorological subdivisions in India. Among the 36 subdivisions, three, constituting 9% of the nation’s total area, received excess rainfall, while 26 subdivisions, accounting for 73% of the total area, witnessed normal rainfall. Seven subdivisions, constituting 18% of the total area, experienced deficient rainfall throughout the season.
It’s worth highlighting that Kerala was among the seven meteorological subdivisions that encountered deficient rainfall. The other regions in this category included Nagaland, Manipur, Mizoram & Tripura (NMMT), Gangetic West Bengal, Jharkhand, Bihar, East Uttar Pradesh, and South Interior Karnataka.
Aside from its variability, this year’s monsoon was marked by two substantial and intense heavy rainfall episodes in Himachal Pradesh, spanning from July 6-15 and August 10-15. These episodes triggered severe flooding due to mini cloudbursts in the state. Additionally, some other regions across the country, such as Chandigarh, Saurashtra, Konkan, and Telangana, experienced exceptionally heavy rainfall, primarily in July.
In conclusion, India’s monsoon season for the year 2023 has notably deviated from the recent four-year trend, concluding with ‘below normal’ rainfall. The interplay of meteorological factors, such as El Nino, and their complex influence on the monsoon’s dynamics underscores the intricate nature of India’s monsoon patterns and their broader implications.
