Pre-monsoon rains begin early this year; meteorologists attribute it to rising temperatures

Other studies have also reported a rise in the moisture content of the atmosphere associated with warming over the Indian region. This increased water vapour under conditions of regional warming may lead to significant positive feedback on human-induced climate change, as water vapour is the most important contributor to the natural greenhouse effect.

India has already been witnessing above-average temperatures this winter season, with December and February being the hottest since 1901.

This year, the initial spell of unseasonal rain and thundershowers led to crop damage in substantial parts of Rajasthan, Madhya Pradesh and Maharashtra between March 6 and 8, with strong winds and hailstorms leading to crop flattening.

Meteorologists say that the country is now gearing up for another prolonged spell of pre-monsoon rain and thundershowers, along with thunderstorms, hailstorms and lightning strikes, with a high likelihood of further crop damage.

The upcoming spell will be a result of the interaction among multiple weather systems. As per the climate models, twin cyclonic circulations are likely to form over East Madhya Pradesh and over Telangana and adjoining North Andhra Pradesh, respectively. A trough is likely to form between these two systems. Both systems would become more marked due to moisture feed from the Arabian Sea as well as the Bay of Bengal on the other side. Besides, an active western disturbance is likely to travel through the Western Himalayas during the same time.

All these systems together will lead to widespread weather activity over central, eastern, and southern parts of the country between March 13 and 18. South Madhya Pradesh, Vidarbha and Marathwada, Telangana, Andhra Pradesh and North Karnataka are likely to experience lightning strikes and thunderstorms. Hailstorm is also likely over Madhya Pradesh and Maharashtra on March 15-16, along with high-velocity winds.

“These weather activities have started a bit early in the season. Usually, pre-monsoon activities commence during the second half of March. Also, rainfall activities during this season are confined to early morning or later afternoons, but such prolonged spells are rare. This season, the abnormal temperatures have triggered multiple weather systems across several parts of the country,” said Mahesh Palawat, Vice President, Meteorology and Climate Change, Skymet Weather.

“There is already a trough which is running through central parts. It will get more marked with a western disturbance which would start affecting the region by March 12. This is a clear example of what kind of climate impacts can be expected with global warming. As the global mean temperatures continue to rise, we would see more of such weather activities at frequent intervals on account of increasing heat stress,” he said.

An increase in the intensity and frequency of extreme rainfall events is mainly influenced by global climate change over Asia. Growth of anthropogenic greenhouse gases in the atmosphere, particularly doubling CO2, is related to the rise in global temperature estimated at an average of 1.5 degrees Celsius.

“Climate change and global warming are known to have significant impacts on the frequency, duration, and intensity of extreme weather events, including heavy rainfall, thunderstorms, and heatwaves. The warmer temperatures resulting from global warming can cause more evaporation, leading to more moisture in the air and heavier rainfall events. Furthermore, climate change can contribute to the formation of localised weather systems, such as thunderstorms and hailstorms, through the increased energy and moisture in the atmosphere,” said Anjal Prakash, Research Director, Bharti Institute of Public Policy, Indian School of Business, and IPCC author.

“These weather systems can cause significant damage to crops, resulting in economic losses for farmers and food shortages for communities. It is important to note that while individual weather events cannot be directly attributed to climate change, the overall pattern of more frequent and severe extreme weather events is consistent with what scientists expect to see as the planet warms. Therefore, it is essential to take actions to mitigate the impacts of climate change and reduce our carbon footprint to prevent further global warming and its associated consequences. This includes implementing sustainable practices in agriculture, reducing greenhouse gas emissions, and investing in renewable energy sources,” Prakash added.

The “maximum warming trend’’ was seen during the pre-monsoon season for the 30 years between 1986 and 2015. The observed surface air
temperature changes over India have been attributed to anthropogenic activities.