This year’s October month was different for India in the context of changing climate. There was heavy rainfall in Northern India, especially in North-Western India. The country received 82.5 mm of rainfall during the first half of October. The climatological normal for the month of October is 76 mm. Since 1901, only 25% of October months have reported an all-India rainfall of more than 80 mm.
However, according to the Indian Meteorological Department (IMD) the country has seen its wettest October during 1975 (121.7 mm) and 1961 (121.3 mm).
As a result of the excessive rainfall in October, summer-sown crops, such as rice, have been at risk, as well as wheat planting has been delayed. The exact data is still awaited but this rainfall has also damaged other crops like cotton, soyabean, pulses etc.
Moreover, not only the economic losses but the severity of the threat has breached the limits beyond which even human survival is difficult.
A case of Eastern Uttar Pradesh
Terai and Eastern regions of Uttar Pradesh have witnessed torrential rains and floods during the same month. The release of floodwater from the Nepal Dams had made the situation more dire. Balrampur (situated near the river Rapti) was identified as the worst-hit district with close to 300 flooded villages. Other districts like Gonda, Sharawasti, Sidhartnagar, Gorakhpur, Barabanki were also hit hard. Hundreds of local people and their livestock are now on the verge of starvation. People were forced to starve and live either on the roofs of their houses or along the road sides. People faced the double whammy of scanty rainfall during the monsoon and floods post-monsoon.
Excessive rainfall in October
This year’s excess monsoon can be explained on the grounds of several interrelated factors. Third consecutive year of excessive cooling of the eastern Pacific ocean, excessive warming of the west Pacific (triple dip La Nina), the development of a low pressure system over central Madhya Pradesh, the collision between retreating monsoon winds and western disturbances, and the warming of the Arctic have all led to higher monsoon rainfall over India this season. During the month of October, the western disturbance formed a trough in the upper and mid troposphere and came in contact with cyclonic circulations forming over south Haryana and the neighbourhood at lower tropospheric levels. This interaction of the western disturbance with the cyclonic circulation led to heavy rains in several parts of Uttarakhand, Uttar Pradesh and Bihar.
However, we shouldn’t limit ourselves to this year’s change in monsoon. The growing erratic nature of the Indian monsoon and shifts in its temporal as well as regional pattern, points towards a long-term change of behaviour of the Indian monsoon. Therefore, one must look deeper into the issue of climate change and its impact on the Indian monsoon.
Changes in Indian monsoon
According to IMD data, the overall monsoon rainfall remains within the 10% range of the long period average (LPA). According to international climate change assessments, it has decreased by 6% over the past 60 years. But a clear prolongation of the Indian monsoon has been witnessed. Formerly limited to the four-month period June-September, the monsoon season now extends into October. There have been shifts in the dates of arrival as well as retreat of the monsoon. For instance, IMD has changed the date of onset over New Delhi from June 27 to June 23. Further, on the one hand, regions of the Indo-Gangetic plains, Meghalaya, Nagaland have experienced reduced rainfall, on the other hand regions of Saurashtra and Kutch, south eastern Rajasthan, northern Tamil Nadu, and areas of southwest Odisha have experienced an increase in rainfall. Rainfall extremes are now up by three times.
These changes are the result of increasing greenhouse gas (GHG) emissions on account of anthropogenic activities like mining, construction, transportation and industrialization. Cities are becoming more vulnerable to climate change as urban heat islands alter evaporation and precipitation rates. In addition to this, warming up of the Arabian sea (where the sea surface temperatures during this monsoon season were 1-2 degrees Celsius above normal) and rising complexities of atmo-oceanic interactions like El Nino Southern Oscillations (ENSO) are further making the Indian monsoon more erratic and violent.
In this backdrop, the recently released United Nation Environment Program’s (UNEP) Emission Gap Report 2022 becomes important. It presents a grim reality and says that the world is falling short of the goals set forth in the Paris Climate Agreement adopted in 2015, and that currently there is no credible pathway to restrict global warming to under 1.5 degrees Celsius above pre-industrial levels. Despite new mitigation pledges for 2030 showing some progress, their insufficiency in terms of global emissions remains the biggest challenge.
Mending the path
It is high time that India must reconsider the definition of the monsoon period. Climate models must be upgraded in order to better cope with the changes happening to the monsoon season over India. Phenomena like El Niño, La Niña, Atlantic Niño and the Arctic warming must be better understood and for that countries must engage in collaborative research engagements. Doppler radar systems must be installed at more places across Indian states, especially the most vulnerable ones.
According to Emission Gap Report 2022, few of the G20 members’ NDC targets put emissions on a clear path towards net-zero pledges. There is an urgent need to back these pledges up with near-term targets and actions that provide confidence that in the end, net zero emissions can be achieved and the remaining carbon budget be maintained.
The Intergovernmental Panel on Climate Change’s (IPCC) 6th assessment report concluded that the frequency of extreme rainfall events will continue to rise in South Asia towards the end of the 21st century. This necessitates a strong demand from the Indian government to take the lead and press for regional cooperation to tackle such situations. As of now, the pace of climate change seems difficult to reverse. Currently, governments must focus on developing better response systems in order to minimize damage to property and lives of the people living in one of the most vulnerable regions of the world.
While the monsoon dances, we cannot remain just an audience!
The views expressed in this article are the author's own.