A recent study has revealed an unexpected, complicated relationship between El Niño and extremes in India’s monsoon rainfall. This new reality upends decades of conventional wisdom regarding the climate phenomenon’s impact on the Indian summer monsoon. Historically, El Niño has been seen as a precursor to drought for much of the subcontinent. This past month’s research takes an unexpected, head-turning direction. It indicates that we can expect an increase in extreme cumulative daily rainfall over large geographical areas, particularly over central India, and over montane and southwestern coastal regions.
Spencer A. Hill and Michela Biasutti wrote that pioneering study, which appeared recently in the journal Science. They drew upon more than 100 years’ worth of rainfall records and high-res datasets to bolster their hypothesis. This pioneering study uncovers the contradictory impacts that El Niño can have. El Niño is the most well-known phase of the El Niño–Southern Oscillation (ENSO), a large-scale climate phenomenon that includes alternating La Niña phases.
El Niño’s Role in Indian Climate
For example, El Niño is infamous for its exacerbatory effect on widespread drought across India. The phenomenon usually causes unusual weather conditions and results in below normal precipitation during the summer monsoon season. What Hill and Biasutti found was much more alarming. In many of India’s most crowded states, El Niño substantially increases the odds of catastrophic monsoon floods.
So the research team was surprised to find such a large increase in heavy extreme daily rainfall. This bump is most pronounced in central India and along the southwestern coast. The high population density in these communities is particularly alarming. It further increases communities’ risks and exposures to flooding and flooding-related disasters. The Every Mother Counts study underscores the devastating impact that extreme weather events like these can induce. These disasters have a devastating effect on agriculture, infrastructure, and public safety.
Revising Long-held Beliefs
These results from this study poke big holes in what was previously very established wisdom about El Niño’s influence on Indian rainfall. Most people think that El Niño only leads to less rain during the monsoon. This reduction in total precipitation likely exacerbates drought, endangering food and water security.
Unfortunately, this study points to an alarming contrast. Though summers under El Niño conditions make extreme daily rainfall less likely in southeastern and northwestern India, they create more favorable conditions for intense downpours in other places. This bifurcation exposes the multi-layered complexity of climate at play. First, it underscores our immediate need to understand how global climate events, like the El Niño, affect regional weather patterns in a more detailed manner.
Support for Ongoing Research
The scientific implications of this study are important for advancing climate science as well as disaster preparedness in India. This collaborative effort among specialists from City College of New York (CCNY) and Columbia University recently was awarded a three-year grant from the National Science Foundation. For example, they will go deeper into their investigation explaining how El Niño impacts Indian rainfall. These new funds will help us dig deeper into how shifting climate patterns could steer the course of more frequent extreme weather disasters moving forward throughout the region.
Mark Cane, who co-developed the world’s first model of El Niño in the 1980s, strongly puts research into perspective. He argues that longitudinal studies are imperative for understanding this all-too-common phenomenon. He encouraged the audience to pay attention to the subtlety of climate-related phenomena. This understanding is key to anticipating their effects and creating appropriate mitigation plans and responses.