Early Summer and Record Temperatures Predicted by IMD
Climate change is strengthening, and its effects are becoming more pronounced, with scientists now warning that the cooling effects typically associated with La Niña might no longer offer relief in an increasingly warmer world. This caution comes amid soaring temperatures observed across large parts of India.
The India Meteorological Department (IMD) forecasts an early summer for the country this year, predicting above-normal temperatures coupled with extended and severe heatwave conditions. February 2025 was recorded as India's hottest February since 1901, accompanied by the fifth-lowest rainfall since 2001, highlighting growing concerns among climate experts.
Climate Change and the 'New Normal'
Human-driven climate change is now consistently producing warmer winters and shorter springs, a phenomenon termed by scientists as the "new normal." However, alongside this steady warming trend, scientists emphasize the significance of annual fluctuations in weather, known as "year-to-year variability."
"For example, updates from the IMD this year suggest that it was an unusually dry winter," explained Arpita Mondal, Associate Professor at the Centre for Climate Studies, IIT Bombay. She noted that rainfall typically helps moderate temperatures through a natural cooling process.
Role of Jet Streams and ENSO in Temperature Extremes
Raghu Murtugudde, an earth system scientist and professor at IIT Bombay, attributed recent temperature anomalies during December-February to global waves of warmth and coldness influenced by shifting jet streams—strong upper-level atmospheric winds. According to Mondal, a northward shift in jet streams during the pre-monsoon months directly impacts the intensity, duration, and temperatures of heatwaves in India.
Climate phenomena such as El Niño and La Niña—phases of the El Niño-Southern Oscillation (ENSO)—also significantly influence weather trends. "Under El Niño-like conditions, you see warmer springs and hot temperatures immediately after winter, whereas La Niña conditions generally result in cooler days," explained Vimal Mishra, Chair Professor of Civil Engineering at IIT Gandhinagar.
Current ENSO Conditions and Unusual Patterns
The World Meteorological Organization (WMO) recently reported that the "weak" La Niña observed since December 2024 is expected to be short-lived. This contrasts the typical ENSO cycle, which alternates between El Niño (warming) and La Niña (cooling) phases every 2 to 7 years, passing through neutral conditions each time.
Commenting on the current state, Murtugudde remarked, "It's not really a La Niña at all. While there are colder waters in parts of the tropical Pacific, warm anomalies have persisted in critical eastern regions. Additionally, this emerged late in the year rather than peaking between December and February."
Murtugudde attributed these unexpected patterns partly to the unprecedented global warming recorded in 2023, which continues to impact weather anomalies today. He pointed out that the current level of warming has yet to be fully explained by scientists.
Intensifying El Niño Events in a Warmer Future
Climate studies project that El Niño occurrences will become more frequent and intense as the world continues to warm, with every second El Niño potentially becoming an extreme event. The recent 2023-24 El Niño event, among the top five strongest recorded, triggered a surge in global temperatures and increased the frequency of extreme weather events.
According to IMD data, India experienced an alarming 536 heatwave days in the summer of 2024—the highest in 14 years—with the northwestern region recording its hottest June since 1901.
Limited Relief Expected from Future La Niña Events
Highlighting concerns, Mishra emphasized that climate change's impact now overshadows traditional weather patterns. "Even under ENSO-neutral conditions—likely this year—we cannot overlook severe heatwaves, especially considering that temperatures in March are already alarmingly high," he added.
With the WMO predicting a 60 percent likelihood of ENSO-neutral conditions persisting through March-May 2025, Mishra warned, "Under current climate change scenarios, while an El Niño can cause significant distress, La Niña might no longer bring sufficient relief."
