NEW DELHI — India has experienced a dramatic warming trend over the past decade, with average temperatures climbing approximately 0.89 degrees Celsius between 2015 and 2024 compared to the early 20th century baseline, according to a comprehensive new study that underscores the accelerating impacts of climate change across the world's most populous nation.

The peer-reviewed research, published in PLOS Climate journal, synthesizes observational data from the India Meteorological Department and global climate models to provide what researchers describe as a critical update on the country's rapidly shifting climate baseline. The findings reveal that India's warming extends far beyond simple temperature increases, triggering cascading effects across multiple environmental systems.

Temperature Extremes Multiply Across Regions

The study documents that the hottest day of each year has warmed even more dramatically than average temperatures, with peak heat increasing by 1.5 to 2 degrees Celsius in western and northeastern India since the 1950s. This intensification has resulted in warm days increasing by five to 10 days per decade across most regions, placing unprecedented stress on populations, agriculture and infrastructure.

The research team, led by climate scientist Chirag Dhara of Krea University in Andhra Pradesh, along with colleagues from the Indian Institute of Tropical Meteorology in Pune, Savitribai Phule Pune University, Norway's Institute of Marine Research, and the International Centre for Integrated Mountain Development in Nepal, emphasizes that while India's warming rate appears relatively moderate compared to global land temperature increases of 1.42 degrees Celsius over the same period, the nation faces unique vulnerability due to its dense population and climate-dependent economy.

"India's climate baseline has shifted," Dhara explains. The analysis identifies regional risk clusters emerging along coastlines, in the Himalayas, and across interior regions, with compound extremes representing an emerging threat category where multiple hazards co-occur or follow in rapid succession.

Himalayan Glaciers Retreating at Accelerated Pace

The Hindu Kush Himalayan region demonstrates particularly alarming trends, experiencing accelerated warming of approximately 0.28 degrees Celsius per decade from 1950 to 2020. This elevated warming rate has directly impacted glacier stability, with mass loss accelerating from 0.17 meter-water equivalent per year during 2000-2009 to 0.28 meter-water equivalent per year in the following decade.

These glaciers serve as crucial water sources for hundreds of millions of people across South Asia, and their accelerating retreat threatens long-term water security for downstream communities. The combination of reduced glacial storage and altered precipitation patterns poses significant challenges for water resource management and agricultural planning across the Indo-Gangetic Plains.

Monsoon Patterns Shifting as Extremes Intensify

The study documents a concerning paradox in India's rainfall patterns. While average southwest monsoon rainfall has declined by 0.5 to 1.5 millimeters per day every decade over the Indo-Gangetic Plains and northeastern India during the past 70 years, extreme precipitation events have simultaneously intensified.

Coastal Gujarat exemplifies this trend, experiencing approximately 0.15 additional extreme rainfall events each decade from 1951 to 2024. This combination of overall drying with more intense downpours creates complex challenges for agriculture and urban planning, as systems must simultaneously adapt to water scarcity and flood risk.

Marine Environments Face Catastrophic Changes

Perhaps the most dramatic projections concern India's marine environments. The tropical Indian Ocean has warmed at 0.12 degrees Celsius per decade since 1950, making it among the fastest-warming ocean regions globally. This oceanic heating drives a projected explosion in marine heatwaves, with duration expected to surge from approximately 20 days per year during 1970-2000 to nearly 200 days per year by mid-century under moderate emissions scenarios.

Marine heatwaves pose grave threats to coral reefs, fisheries and coastal ecosystems that millions of Indians depend upon for food security and livelihoods. The Arabian Sea has emerged as a particular hotspot, with the maximum intensity of pre-monsoon cyclones increasing by 40 percent in recent decades.

Rising sea levels compound these marine threats. The research projects that extreme sea-level events that historically occurred once per century will become annual occurrences by mid-century, dramatically elevating risks for coastal populations and infrastructure. The Sundarbans region, a critical mangrove ecosystem and densely populated delta, faces combined pressures from sea-level rise, increased heat stress and more intense storms.

Future Warming Locked In Under Current Trajectories

Climate models project additional warming of approximately 1.2 to 1.3 degrees Celsius over India by mid-century under the SSP2-4.5 scenario, a moderate emissions pathway, relative to the 1995-2014 baseline. This "middle of the road" scenario assumes continued fossil fuel use alongside some climate mitigation efforts.

The prospect of compound climate hazards represents a particularly concerning dimension of future climate risks. Events where multiple hazards interact, such as simultaneous heatwaves and droughts, produce impacts far exceeding those of individual events occurring in isolation. However, research on these compound extremes remains sparse in the Indian context, according to the study authors, who emphasize the critical importance of accelerating research in this area.

Regional Variations Demand Targeted Responses

The study's regional analysis reveals significant geographic disparities in climate impacts across India. Northwest India has witnessed notable increases in both warm days and warm nights, while western India faces rising extreme rainfall alongside elevated temperatures. The western coast experiences increased severe tropical cyclones combined with sea-level rise.

Central India shows intensification of extreme rainfall events, while southeastern regions experience more warm days and nights plus increased rainfall during the northeast monsoon season. These regional variations underscore the need for tailored adaptation strategies rather than one-size-fits-all approaches.

The Indo-Gangetic Plains face a particularly complex challenge, combining increased heat stress with declining monsoon rainfall. This populous agricultural heartland must adapt simultaneously to water scarcity and extreme heat, requiring significant investments in water management infrastructure, heat-resilient crop varieties and early warning systems.

Urgent Adaptation Imperative Emerges

The research team emphasizes that climate adaptation can no longer be treated as optional for India. The findings underscore urgent needs for robust, region-specific adaptation strategies grounded in latest climate science, including resilient infrastructure development, multi-hazard early warning systems, and climate-smart agricultural practices.

Greater investment in climate research and data collection emerges as a critical priority, particularly for understanding compound extremes and their impacts on various sectors and communities. The authors note that while India has made progress through initiatives like Heat Action Plans in multiple cities, responses remain largely reactive and incremental rather than transformative.

Vulnerable populations, including outdoor workers, informal settlement residents, elderly individuals, pregnant women and children face disproportionate risks from intensifying heat and extreme weather. Targeted protection measures for these groups represent both a humanitarian imperative and an economic necessity, as climate impacts increasingly strain public health systems and reduce labor productivity during extreme events.

Global Context and India's Climate Challenge

India's climate transformation occurs within the broader context of accelerating global warming. The year 2024 marked the warmest year globally on record, with temperatures exceeding 1.5 degrees Celsius above pre-industrial levels for the first time. India itself recorded its warmest year since 1901 in 2024, with average minimum temperatures settling 0.90 degrees Celsius above long-term averages.

As climate impacts intensify, India faces the dual challenge of protecting its 1.4 billion citizens from escalating climate risks while pursuing economic development to lift millions out of poverty. The nation has emerged as a global leader in renewable energy deployment, yet also remains heavily dependent on coal for electricity generation.

The study's release comes as international climate negotiations continue to grapple with questions of emissions reductions, climate finance, and adaptation support. For India, translating climate science into effective policy action across national, state and local levels represents an increasingly urgent imperative as the window for preventing the worst impacts continues to narrow.

The researchers conclude that with India's climate baseline fundamentally shifted, the question is no longer whether adaptation is necessary, but rather how quickly and comprehensively the nation can implement the transformative changes required to build resilience against an increasingly volatile climate future.