Kerala’s Early Heat Surge Signals Climate Shift

Kerala, known for its clear skies and balmy weather during the early part of the year, which attracts tourists, has been grappling with an early start of unusually hot weather this season. Scientists attribute this to a mix of local weather conditions and long-term climate change impacts.

As temperatures soared, on February 20, the India Meteorological Department (IMD) forecast for temperatures was 2 to 3 degrees Celsius above the seasonal average in isolated places in Kerala. This followed a week that saw Palakkad district reporting some of the highest temperatures in the country – above 38 degrees Celsius.

The year began with temperatures in parts of India often crossing 35 degrees Celsius, an unusual occurrence, as observers note. On January 24, for instance, Kannur Airport area in Kerala recorded 36.6 degrees Celsius, while much of north India was dealing with a severe winter. Kottayam, also in the southern state, came a close second with 36.5 degrees Celsius.

On ground

For those who work outdoors, the high temperatures meant staying away from work much of the day. The Kerala State Disaster Management Authority advised farmers and outdoor labourers to work only early in the morning and evening when the temperatures reduced.

At Puthenthope village across the northern fringes of Thiruvananthapuram, where raft fishing is prevalent, fishers rest under the dense canopy of the coconut groves in the backdrop of a calm sea lit up silver in bright sunlight. “It is just an early morning trip that works – or one at night,” said Terrance Miranda, a veteran fisherman.

Sajith Remady, an art teacher from a nearby village who offers outdoor lessons, said. “It is just a burnt-out landscape out there, under the sun. We just cannot work after mid-morning.”

In southern Thiruvananthapuram, on the severely eroded shores of Pozhiyoor, raft fishing is increasingly challenging anyway, local fishers said. “Now we go to fish only early in the morning and get back by around 8 am,” said Mariyannii Miyyelpillai, a traditional raft fisherman in his 70s. “It is so hot; we cannot stay in the sea under the sun.” Miyyelpillai said that raft fishers preferred pleasant weather as it involves sheer manual labour, but nowadays it is just not possible to fish during the day because of the heat.

Elsewhere, traditional fishers who go on longer forays on motorised fibreglass craft said they take many bottles of water with them to cool themselves down. Old-timers said they cover their head with a towel, and many youngsters wear caps – a rather new practice, they said.

Contributing factors

Local scientists attribute the current rise in temperature to local conditions coupled with long-term climate change impacts. “There is a high-pressure system over the Arabian Sea, and much of mainland India,” Abhilash S., director of the Advanced Centre for Atmospheric Radar Research, Cochin University of Science and Technology, told Mongabay India. That prevents the cooling effect of winds, and combined with high humidity, is expected to elevate the perceived temperature, he explained.

However, later, as March begins, the temperatures are likely to come down with cooling rains, Abhilash said. He attributes it to the effects of the Madden-Julian Oscillation (MJO), which is expected to bring rain. MJO is an eastward moving system comprising clouds, rainfall, winds, and pressure that traverses the tropics in cycles of 30 to 60 days, influencing weather patterns. An active MJO phase is associated with more rain.

“There has been MJO activity since the beginning of 2025, with the enhanced phase propagating across the Western Pacific and entering the Western Hemisphere during the past week,” noted Climate Prediction Center (CPC) scientists. The CPC comes under the U.S. National Oceanic and Atmospheric Administration (NOAA).

A clear trend of warming

Senior IMD scientist V.K. Mini at the Meteorological Centre Thiruvananthapuram told Mongabay India, “Unusually high temperatures recorded on the coastal areas show that the ocean temperatures remain high in line with climate change trends reported in this region.” Scientists can say more about the summer trends in Kerala once we have the outlook by the end of February, she said.

The question scientists ask is whether this summer will see the next more dangerous step: heat waves. That involves a temperature of 40 degrees Celsius on the plains or a departure of 4.5 degrees Celsius from normal. Southwestern India, including Kerala, Karnataka, Goa, and parts of Maharashtra and Tamil Nadu, is experiencing rising temperatures and an increasing frequency of extreme heat events are becoming more frequent, shaped by key oceanic climate patterns, as Mongabay India reported.

In addition to the El Niño–Southern Oscillation (ENSO), factors such as the Pacific Decadal Oscillation (PDO), which cycles between ‘cool’ and ‘warm’ phases every 20 to 30 years, and the Indian Ocean Dipole (IOD), which drives east-west variations in oceanic and atmospheric conditions, play a significant role in heat waves. Research also highlights a strong connection between heat waves in India and sea surface temperatures in the Atlantic Ocean.

These warm weather events underscore a clear trend toward a hotter climate, as detailed in a recent report by the state’s Institute for Climate Change Studies. Kerala experienced its hottest year on record in 2024, with the state’s average annual land surface temperature rising 0.99 degree Celsius above the long-term average (1991–2020), according to the report. This crosses the previous record set in 2016, which saw a 0.77 degree Celsius increase, and 2023, which recorded a 0.76 degree Celsius anomaly. The findings mark a significant shift in the state’s climate trends, with temperatures steadily climbing since the early 20th century, the institute scientists noted.

The rising temperatures in Kerala are part of a broader pattern observed globally. The southern state recorded 2024 as the warmest year since 1901. This aligns with global observations, where 2024 was likely the warmest year on record, with average temperatures 1.5 degrees Celsius above pre-industrial levels.

The U.K. Met Office noted that the global average temperature for 2024 was 1.53 degrees Celsius above the 1850-1900 average. The NOAA also declared that 2024 was the hottest on record, with Earth’s average land and ocean surface temperature rising 1.29 degrees Celsius above the 20th-century average. It edged past 2023 — the previous record-holder — by 0.10 degrees Celsius, reinforcing a pattern of accelerating global warming. Across the world, Africa, Europe, North America, Oceania, and South America (which tied with 2023) all recorded their warmest year. Asia and the Arctic saw their second-warmest year.

The trend is stark: the 10 hottest years since 1850 have all occurred in the past decade, according to NOAA’s data.

Regional influences

IMD scientists have reported a trend of warming involving a combination of factors: higher average temperatures, shifting monsoon patterns, and a growing number of heat wave days. Researchers also point to rapid urbanisation and deforestation as key contributors, altering local climate conditions and intensifying the region’s heat burden.

One of the most pressing concerns is the rise of urban heat islands, where densely built environments trap and retain more heat than nearby rural areas, leading to intense localised warming. With shrinking green spaces and expanding concrete and asphalt surfaces, cities in the region face heightened vulnerability to prolonged heat stress. Studies suggest that, without intervention, extreme heat events will become even more frequent and severe, raising concerns over public health, water scarcity, and food security.

Experts at IMD call for implementing sustainable preventive measures, including enhancing early warning systems to deliver timely heat wave alerts and establishing guidelines for protective actions. The National Disaster Management Authority, for instance, issues advisories for people exposed to heat waves.

As for long-term planning, experts have advised a set of measures to cool down local environments. These measures include cool roof and cool buildings with appropriate painting and greening, blue-green infrastructure linking water sources and green spaces, and effective use of riverfronts, seashores, and urban forests. As Reshmi M.K., associate professor in the architecture department at Christ University, Bengaluru, summed it up to Mongabay India, what we need is a planning process effectively “integrating blue, green and grey.”

(Published under Creative Commons from Mongabay-India. Read the original article here)