From predictable to perilous: How climate change is reshaping the monsoon

The southwest monsoon has been advancing rapidly due to oceanic and atmospheric factors and is likely to make landfall over the subcontinent this weekend. IMD updates said the monsoon is likely to strike Kerala and the Northeast almost simultaneously.

The normal onset date for monsoon over Kerala is June 1 and over Northeast India is June 5. The patterns of monsoons have been undergoing significant changes over the last few decades, primarily due to climate change. Monsoons are traditionally known for their predictable arrival, but in recent years, there have been signs of unpredictability, with delayed or earlier arrivals than usual. The pre-monsoons have been kind to Assam this year, with the State witnessing incessant rains almost throughout the season (since March 1 till date), and the daytime temperatures remaining more or less at comfortable levels. However, despite intermittent rains, the State has recorded a 14 percent deficit in pre-monsoon rainfall (from March 1 to May 21).

There has been a sharp contrast in district-wise rainfall statistics in the pre-monsoon season, but that is normal in this season. Majuli saw around 128 percent excess rains, while pre-monsoon rainfall in Biswanath has been deficit by 82 percent. The pre-monsoon season was also marked by two significant phenomena – Dibrugarh saw its highest ever 24-hour April rainfall (187.7 mm) on April 24, while Guwahati recorded the highest ever 24-hour May rainfall (99.6 mm) on May 20.

The Indian monsoon is a complex phenomenon, influenced by a range of factors, including the temperature difference between land and sea, the Indian Ocean Dipole, and the El Nino phenomenon. One of the most noticeable changes in India’s monsoon patterns is an uneven distribution of rainfall. While some regions experience an early or heavy burst of rain, others receive less rainfall than expected.

This erratic monsoon rainfall is bound to affect the agriculture sector, as many States are heavily reliant on rains. Groundwater levels in many parts of the country also rely on the replenishment from the monsoon. Besides, insufficient rains have been hitting hydropower generation. Rising instances of extreme weather events during the monsoons, such as drought-like conditions or intense and concentrated rainfall events, are also becoming increasingly marked.

The shifting monsoon patterns present a major challenge to both rural and urban populations. Agriculture, water resources, infrastructure, health, and biodiversity are all at risk from the unpredictability and extreme nature of the changing monsoon. To mitigate these risks, the government needs to adopt climate-resilient agricultural practices, improve infrastructure, and invest in early warning systems for extreme weather events. Enhanced cooperation between the government, NGOs, and communities will be crucial in adapting to these changes and ensuring long-term sustainability.