More than Half of India's Districts Vulnerable to 'High to Very high' Heat Risk: Study

More than half of India's districts are vulnerable to 'high to very high' heat risk, according to a recent study by Delhi-based think tank Council on Energy, Environment and Water.
The top 10 states and union territories that are threatened by the highest heat risk are Delhi, Maharashtra, Goa, Kerala, Gujarat, Rajasthan, Tamil Nadu, Andhra Pradesh, Madhya Pradesh and Uttar Pradesh.
The study recommends that Heat Action Plans – which are currently used at the district level to prepare for heat hazards and exposure – be updated regularly, and that it take into account aspects such as the rise in warmer nights and relative humidity which the study noted as new trends over the past decade.
India has been experiencing record-breaking heat in recent times.
For instance, the India Meteorological Department (IMD) announced that February 2025 was the hottest that India has witnessed in 125 years. Last year, in a first, Mungeshpur in northwest Delhi clocked 52.3° Celsius in May (which authorities put down as an 'outlier' possibly due to 'sensor errors').
Per the IMD, a heatwave is said to occur over a region if the maximum temperature goes above 45°C, or when temperatures increase from between 4.5°C and 6.4°C above the normal; and a severe heatwave is said to occur when maximum temperatures exceed 47°C, or rises above normal levels by 6.4°C and higher. Both are known to impact people – their health and livelihoods – in several ways. Some sections of people are more prone to these heat hazards than others. According to the United Nations' Intergovernmental Panel on Climate Change (IPCC), heat risk is a combination of heat hazard, exposure and vulnerability.
A team of scientists at the Council on Energy, Environment and Water (CEEW), Delhi, developed a heat risk index (HRI) for 734 districts in India to assess heat risk at district-level across the country. They mapped long-term heat trends from 1982 to 2022 using both satellite imagery and the Indian Monsoon Data Analysis and Assimilation, which is a high-resolution climate dataset. The team also included several other variables in their analyses, such as socio-economic and health factors, land-use, population and green cover while also looking at trends in night-time temperatures and relative humidity levels.
The Heat Risk Index in the report of the Council on Energy, Environment and Water.
on May 20, showed that 57% (417) of India's 734 districts – which are home to more than three-quarters of the country's total population – are currently at high to very high heat risk. Specifically, 151 districts fell under the 'high risk' category and 266 under the 'very high risk' category. While 201 districts fell in the moderate category and 116 fell either in the low or very low categories, this does not mean that these districts are free of heat risk, but instead that heat risk in these districts is relatively lesser when compared to others, according to the study.
The team aggregated these risks at the state level and found that the ten states and union territories with the highest heat risk are Delhi, Maharashtra, Goa, Kerala, Gujarat, Rajasthan, Tamil Nadu, Andhra Pradesh, Madhya Pradesh and Uttar Pradesh.
They also found that while the number of very hot days is increasing in India, the number of very warm nights is increasing at an even greater rate. Over the last decade, nearly 70% of India's districts experienced an additional five very warm nights per summer (March to June). In comparison, only ~28% of districts experienced five or more additional very hot days.
This is a concern because usually, when daytime temperatures increase, nights cool down providing much-needed relief to people. However, when nights get warmer, the human body finds it harder to cope with the increased daytime temperatures and unusually warmer nights.
Cities and the urban heat island phenomenon
The team found that the urban heat island effect – where increased urbanisation and the resulting concretisation keeps temperatures in built-up areas far higher than it would have been if it had green cover – also plays a role in this trend in the increase in very warm nights.
Their data showed that the rise in very warm nights is 'most noticeable' in districts with a large population (over 10 lakh), which are often home to tier I and II cities. Per the study, just over the last decade alone, several metros witnessed an additional number of very warm nights per summer: Mumbai witnessed 15, Bengaluru 11, Bhopal and Jaipur witnessed seven each, Delhi experienced six additional very warm nights, as did Chennai (4).
'This increase can be attributed to the urban heat island effect, where cities trap heat during the day and release it at night, thus increasing nighttime temperatures. With nearly 50 per cent of India's population expected to live in urban areas by 2050, this poses a serious threat to the population (UN-DESA 2018),' the study noted.
It also found that districts with increased heat extremes but lower vulnerability – such as in Odisha – had higher green cover and better blue infrastructure: 'factors enhance adaptive capacity, helping communities cope more effectively with extreme heat'.
Increases in relative humidity is yet another concern. Per the study, the Indo-Gangetic plain experienced the highest summer relative humidity increase in the last decade. 'Cities like Delhi, Chandigarh, Jaipur, and Lucknow are also experiencing a 6 to 9 per cent rise in relative humidity,' the CEEW study noted.
'Danger doesn't end when the sun sets'
According to the study, the phenomena of increased warm nights and relative humidity need to be factored into existing Heat Action Plans, which are documents that outline strategies and measures to prepare for, respond to and mitigate the impacts of extreme heat events.
India must invest in 'long-term resilience', commented Vishwas Chitale, Senior Programme Lead at CEEW, and a co-author of the study. 'Solutions like parametric heat insurance, early warning systems, net-zero cooling shelters, and cool roofs must become core to heat action plans. States like Maharashtra, Odisha, Gujarat and Tamil Nadu are already taking pioneering steps by integrating climate and health data into local planning. Now is the time to scale these efforts nationally, using district-level risk assessments to prioritise funding and action,' Chitale said in a statement.
'Heat stress is no longer a future threat – it's a present reality,' Arunabha Ghosh, CEO of CEEW, said in a press statement. 'Increasingly erratic weather due to climate change – record heat in some regions, unexpected rain in others - is disrupting how we understand summer in India. But the science from the study is unequivocal: we are entering an era of intense, prolonged heat, rising humidity, and dangerously warm nights.'
He added that city-level Heat Action Plans must be 'urgently overhauled' to address local vulnerabilities, balance emergency response measures with long-term resilience, and secure financing for sustainable cooling solutions.
'Further, it's time to move beyond daytime temperature thresholds and act on what the data tells us: the danger doesn't end when the sun sets.'

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The Print

3 hours ago

• The Print

From climate change to infra collapse, why deadly floods have become Northeast's new normal – ThePrint

Arunachal saw a tragic landslide that killed nine people, including children and pregnant women. In Meghalaya, Cherrapunji recorded more than 300 mm of rainfall in a single day, triggering fatal mudslides. Landslides and flash floods in Tripura and Mizoram displaced thousands and forced emergency evacuations. In just the first wave of this year's monsoon, states like Assam, Meghalaya, Arunachal Pradesh, Mizoram, and Tripura were overwhelmed. Assam alone reported over 6.8 lakh people affected, nearly 50 deaths, and thousands of hectares of cropland under water. New Delhi: The Northeast was battered by devastating floods this year, displacing thousands and claiming dozens of lives. Experts say it's time the government addresses a mounting crisis in the region—soil erosion, frequent landslides, and increasingly destructive extreme weather events A new normal in the Northeast? Over the past few decades, the Northeast, perched on fragile slopes and crisscrossed by swelling rivers, has seen a growing number of extreme weather events. India Meteorological Department (IMD) data shows that while overall monsoon rainfall has marginally declined over the last 30-40 years, the intensity and frequency of short, heavy downpours—150 mm or more in a day—have risen sharply. In states like Meghalaya and Assam, these events have quadrupled since the 1950s. Dr D. Sivananda Pai, head, climate research and services at the IMD, explains that this surge in extreme rainfall is not an anomaly but increasingly a 'normal characteristic of the region'. This year, he points out, a significant amount of moisture convergence was observed in the Northeast—driven by warm temperatures and high humidity. 'Because of rising temperatures, the air can hold more moisture. So when it rains, it rains very heavily, in a short span.' What this means is a shift not just in volume but in distribution: fewer rainy days overall, but a spike in extreme events. According to Pai, this pattern now extends beyond the Northeast and is also visible across Northwest India, the west coast, and even parts of central India. Kartiki Negi, a climate impacts lead at Climate Trends, a climate research consultancy, said that there has been a clear intensification of rainfall events across the country, attributing it to a mix of land and ocean warming. 'We're seeing more frequent extreme events driven by a combination of warmer air, early monsoon onset, and moisture incursion from the Bay of Bengal.' she said. In the Northeast, this effect is further amplified by the region's topography. The eastern Himalayas act as a barrier, trapping moisture-laden winds and often leading to sudden cloudbursts. 'The Himalayas react more aggressively to global warming. A 1.5 degrees Celsius rise globally can mean nearly 2 degrees Celsius locally in the hills.' Despite being one of the largest contributors to the national monsoon average, the Northeast has repeatedly failed to meet its seasonal norms in recent years. 'Of the last 8–10 years, the region has underperformed in most,' Kartiki noted. The high normal baseline—around 300 cm in many areas—means even slightly lower rainfall registers as a deficit. And yet, paradoxically, when rain does arrive, it's often in destructive bursts. Dr Pai explains it further, 'Even if 50 cm of rain comes suddenly in a place that normally gets 300, it's still heavy enough to cause flooding.' Both experts agree that this volatile pattern is now the defining signature of climate change in India: not just more or less rain, but rain that comes harder, faster, and less predictably—especially in hilly regions from the Northeast to Himachal Pradesh, Uttarakhand, and Kashmir. 'Whenever it rains, it rains like anything,' says Pai. 'Then there's a long dry spell. That's the new pattern—and it's showing up across the country.' Gyatso Lepcha, an environmental activist and social entrepreneur, also known as the 'River Man' of Sikkim for his protecting the free-flowing Teesta river and its tributaries, warns that the Himalayan state's fragile ecosystem is reeling from erratic weather patterns driven by climate change. 'The north of Sikkim is especially vulnerable,' he said, pointing to its high peaks, glaciers, and delicate ecology. ThePrint reached Prabhakar Rai, Director, Sikkim State Disaster Management Authority via calls and email. This report will be updated if and when a response is received. Over the past decade, sudden cloudbursts and intense, short-duration rainfalls have become common. 'It's not raining anymore—it feels like someone is dumping buckets of water,' he said. A 20-minute downpour now routinely causes landslides and destruction across the region. This is no longer a localised crisis. Lepcha pointed out that the entire northeastern Himalayan belt—from Arunachal and Nagaland to Manipur and Meghalaya—is experiencing simultaneous and severe rainfall-triggered disasters. 'Earlier, one or two states would get hit. Now it's all of us, at the same time,' he noted Also Read: Central & state surveys throw up same, grim result—Bengaluru groundwater depleting at dangerous pace Changing nature of the river of sorrow The Brahmaputra, which originates from the Angsi Glacier near Mount Kailash in Tibet and enters India in Arunachal Pradesh as the Dihang, it flows southwest across Assam as the Brahmaputra, and finally enters Bangladesh, where it becomes the Jamuna before merging with the Padma (Ganges) and emptying into the Bay of Bengal. Known for decades as the 'sorrow of Assam', its monsoon fury has long shaped lives and landscapes in the northeast states especially Assam. As Kartiki from Climate Trends points out, the region is inherently flood-prone—owing both to topography and high rainfall in the Indian stretch of the basin. But while floods have always been part of the river's character, their nature has changed. 'Earlier, floods brought fertile silt and replenished ponds with fresh fish,' recalls Professor Chandan Kumar Sharma from Tezpur University in Assam. 'People—even in their 60s today—remember looking forward to floods.' That, however, has given way to anxiety. Today, Brahmaputra's floods bring more destruction than renewal. According to the experts, this shift is tied to the river's sediment load and changing rain patterns. Brahmaputra is one of the most silt-laden rivers in the world. But instead of spreading nutrient-rich silt, floods now deposit coarse sand, rendering farmlands infertile. Villages across upper Assam are grappling with this phenomenon, locally referred to as 'sand-casting'. These deposits degrade the soil and render fields unusable for agriculture. This change in sediment dynamics is linked to another, more pressing shift: the changing pattern of rainfall. Prof Sharma attributes the worsening floods to increasingly concentrated bursts of rain, often followed by dry spells—creating a double blow of flood and drought. This volatility is worsened by the region's diminishing ability to absorb and channel rainwater. Hills, once natural buffers, now allow unchecked runoff due to deforestation and unregulated construction. Adding to this is the way human interventions are reshaping the river's ability to handle water. Himanshu Thakkar, an environment expert and the coordinator of South Asia Network on Dams, Rivers and People (SANDRP), explains that flooding occurs when rainfall exceeds an area's ability to absorb, store, or drain water. 'The moment your capacity to harvest or recharge water is lower than the input, flooding is inevitable,' he says. Unfortunately, that capacity is steadily declining. Deforestation, encroachments on wetlands, and poorly planned embankments are all shrinking this capacity. Thakkar points out that embankments—meant to expedite drainage—often do the opposite. In a river as silt-heavy as the Brahmaputra, embankments trap debris and boulders upstream. Over time, sediment settles along the riverbed, reducing the channel's depth and its ability to carry water. 'That weakens the flood-draining function it was designed for,' he notes. What was once a predictable, even beneficial natural rhythm has now become an annual threat—made worse by ecological degradation and fragmented planning, he said. Assam—the worst-hit state Assam remains the worst-affected by India's annual flood crisis. In 2024, over 2.45 million people across 30 districts were affected, and 52 were killed. Two years before that, in 2022, the state witnessed its worst floods in a decade—three prolonged waves of deluge between April and October displaced over 4.7 million people and damaged 108,000 hectares of cropland. The Assam State Disaster Management Authority (ASDMA) data shows that the state has recorded over 500 embankment breaches between 2011 and 2022. The year 2015 alone accounted for 283 breaches, the highest in any single year during that period. Many of these past their expiry, according to the experts, gave way to water pressure. But the destruction, experts argue, isn't just a result of climate change. Local mismanagement has compounded the crisis. Heavy deforestation in upstream hills, especially around Meghalaya and near Guwahati, Assam's largest city, has left the land stripped of its ability to hold rain. 'Earlier, the hills had trees and grass to slow water down. Now, with hill-cutting and concrete replacing forest, rain just rushes down into low-lying areas,' said Prof. Sharma of Tezpur University. Assam Chief Minister Himanta Biswa Sarma has also flagged concerns about hill-cutting in neighbouring Meghalaya worsening runoff into Assam's floodplains. Guwahati, once flanked by wetlands, now drowns under its own growth. 'Every empty space has been built over. So where will the water go?' asks Prof Sharma. The city's drainage network is overwhelmed, wetlands have been encroached upon, and concretisation has robbed both urban and rural Assam of natural water retention systems. Even paddy fields in villages—once capable of absorbing floodwater—are being flattened for infrastructure. Adding to this is the uncoordinated release of water from upstream dams. From neighbouring country Bhutan's Kurichhu Dam in the west to Ranganadi Lower Subansiri district of Arunachal Pradesh, operational dams often release excess water without warning. 'Recently, the Ranganadi project in Lakhimpur released water without informing district authorities—leading to severe flooding,' Prof Sharma noted. ThePrint reached Arunachal Pradesh State Disaster Management Authority Director Kanki Darang via calls and email; and Assam State Disaster Management Authority Chief Executive Officer Gyanendra Dev Tripathi via email. This report will be updated if and when responses are received. In short, what's unfolding in Guwahati is a snapshot of what's happening across Assam: embankments breaching, wetlands vanishing, farmlands buried under sand, and cities choking in concrete—with no coherent floodplain management to match the scale of the challenge. 'Overlooking government policies' While climate change remains a global crisis, environmentalists and scholars argue that India's development model has worsened the situation in ecologically fragile Himalayan states. 'We didn't create the climate crisis, but we are bearing the brunt of it,' Lepcha said. He was especially critical of hydroelectric dams, roads, railways, and other mega-infrastructure projects pushed into ecologically sensitive zones. 'Every river in Sikkim has been tapped,' he said, pointing to the Teesta River, the state's only major outlet, now choked with dams. Lepcha recalled the 2023 Glacial Lake Outburst Flood (GLOF), which led to the collapse of one of the biggest dams in Sikkim. 'It was one of the worst dam disasters in the country, and yet it barely made headlines,' he said. The destruction that followed has left infrastructure in ruins and communities disconnected even today. He noted that similar patterns of devastation—road collapses, blocked communication lines, and recurring landslides—are now routine across the Northeast. 'The road from Dimapur to Imphal, for instance, was cut off again just days ago,' he said, adding that repeated disasters show how fragile the region really is. Echoing similar concerns, Prof. Sharma stressed the urgent need for a comprehensive flood management policy. 'I'm not talking about flood control—floods can't always be controlled,' he clarified. 'But there must at least be a clear flood management strategy.' Yet, he said, even major hydroelectric projects lack basic flood mitigation mechanisms. He cited examples such as the Subansiri Dam, the Ranganadi, Kurichhu, and several others across central Assam and the hills of Karbi Anglong and Meghalaya. None of them, he argued, have been designed with flood control in mind. 'So obviously, the severity of the situation will only increase,' he said. 'People used to live with floods; they even welcomed the seasonal floods in the past. But now, the scale and intensity of these floods have become so severe that survival itself is becoming unsustainable.' Brahmaputra board & northeastern council The Indian government has long had institutional frameworks in place to address floods and erosion in the Northeast—chief among them, the Brahmaputra Board. Set up under the Brahmaputra Board Act, 1980, and operational since January 1982, it was tasked with preparing master plans for flood control, bank erosion, drainage, irrigation, hydropower, and navigation across the Brahmaputra-Barak basin, which spans much of the Northeast as well as parts of West Bengal. It operates under the Ministry of Jal Shakti. But despite the board's expansive mandate and decades of central funding, its track record has repeatedly come under scrutiny—most recently in Assam's Majuli, the world's largest river island, which continues to suffer from continuous land erosion. In 2017, a Rs 233-crore project was sanctioned to protect Majuli. As of 2024, according to media reports, while the Brahmaputra Board claimed that nine major projects were 97 percent complete, yet, infrastructure failures persist. Bamboo bridges have collapsed, geo-bags have been swept away, and land continues to erode. Independent research shows that since 1960, Majuli has reportedly lost over 4.27 lakh hectares of land to erosion—nearly half the island. 'Assam's experience with the Brahmaputra Board has not been encouraging at all. Their role was supposed to be scientific flood management and river studies—but nothing much has come of it,' said Prof. Sharma. Alongside the board, the North Eastern Council (NEC) was created to serve as the nodal agency for economic and social development across the eight Northeastern states. Flood control and watershed management fall within its broader planning functions. Between 2017 and 2022, the NEC allocated nearly Rs 139.9 crore for anti-erosion and flood mitigation projects in Assam, Arunachal Pradesh, Meghalaya, and other hill states. ThePrint reached the Brahmaputra Board Chairman Ranbir Singh, and North Eastern Council's Director Administration L.S. Gangte via emails. This report will be updated if and when responses are received. It supported initiatives like satellite-based early warning systems through partnerships with NESAC (North Eastern Space Applications Centre). Yet, like the Brahmaputra Board, NEC's involvement tends to be advisory and funding-oriented—on-ground execution is left to state agencies, where delays and inconsistencies often dilute impact. In contrast, the Central Water Commission (CWC) plays a more active, operational role—particularly in real-time flood forecasting. It maintains a network of river gauges across flood-prone regions of Assam and the broader Northeast, issues daily or hourly flood bulletins, and tracks rivers breaching danger levels. These alerts are critical for evacuation and emergency preparedness, but CWC does not have the mandate to construct or repair embankments or erosion-control infrastructure. That responsibility lies with state governments. While CWC's forecasts are largely accurate and technically robust, their effectiveness on the ground often depends on local-level response and coordination. Tourism, a major economic pillar for the Northeast, is also collapsing under the weight of climate unpredictability. 'The monsoon is just beginning, and already we're seeing fresh havoc,' Lepcha said. He emphasised that strategic concerns—like countering China—should not justify ecological destruction. 'Yes, we need roads for security, but we also need to think long-term.' (Edited by Sanya Mathur) Also Read: Not just oil, capsized Liberian ship poses another environmental threat. It's all over Kerala & TN coasts

Hindustan Times

4 hours ago

• Hindustan Times

Monsoon may reach Delhi by June 24, three days ahead of normal date: IMD

The southwest monsoon is expected to reach Delhi by June 24, advancing three days before the normal date (June 27), as the conditions are becoming favourable for the same, the India Meteorological Department (IMD) said. 'Southwest monsoon has further advanced into remaining parts of Bihar and east Uttar Pradesh and Madhya Pradesh, some parts of west Uttar Pradesh, most parts of Uttarakhand, many parts of Himachal Pradesh and some parts of Ladakh,' IMD posted on their social media handle on X (formerly Twitter), on Friday. IMD said that the conditions are favourable for further advancement of southwest monsoon over remaining parts of North Arabian Sea, Rajasthan, West Uttar Pradesh, Uttarakhand, Himachal Pradesh and Jammu and Kashmir-Gilgit-Baltistan-Muzaffarabad, and parts of Ladakh during the next two days. Also Read: AAP slams Delhi CM Rekha Gupta for 'false promises' over waterlogging in capital 'Conditions are also becoming favourable for further advance of southwest monsoon over remaining parts of Jammu & Kashmir, Ladakh; Punjab, Haryana, Chandigarh and Delhi during subsequent two days,' the Met department added. Last year, the onset of monsoon in Delhi was recorded on June 28 and June 25 in 2023. Meanwhile, a yellow alert remained in place for the day and the weekend, with IMD forecasting rain and thunderstorms. 'Generally cloudy skies will persist throughout the day and for the next few days. Very light to light rain may be recorded towards the evening or night on Friday, accompanied by thunderstorms, lightning and gusty winds of speed 30-40 kmph, even reaching 50 kmph during the thunderstorm,' said an IMD official. 'Satisfactory' AQI Delhi's air quality index (AQI) remained in the satisfactory category for a third consecutive day on Friday and was recorded at 76 (satisfactory) at 3pm, in comparison to the 24-hour average AQI of 89 recorded on Thursday. Delhi had also recorded its 24-hour average of cleanest air in eight months on Wednesday, with AQI being 81 (satisfactory). This was the lowest since September 29 when AQI had stood at 76. With the onset of monsoon on the horizon, Delhi's AQI is expected to remain in the satisfactory category for the next few days, according to forecasts by the Air Quality Early Warning System (AQEWS).

News18

4 hours ago

• News18

Rain Havoc In Pune: IMD Issues Orange Alert, More Showers Forecast

Last Updated: Pune Rain: Due to heavy rain, water entered several surrounding localities and housing societies in low-lying areas along the Mutha River on Thursday. Heavy rain lashed Pune on Thursday night, with the India Meteorological Department (IMD) sounding an alert even for Friday morning. The rain started late Wednesday and intensified on Thursday. Orange alert remains in place even for Friday, as per IMD predictions. The weather department has forecast generally cloudy skies with moderate and heavy rainfall. With heavy rain in the city, water entered several surrounding localities and housing societies in low-lying areas along the Mutha River on Thursday. Water released from the Khadakwasla dam, which supplies drinking water to the city, worsened the situation for such areas. 'As the water level of Khadakwasla Dam is rising due to heavy rainfall in the catchment area, water is being released. The water discharge increased to 4,300 cusecs at 4 pm," an irrigation department official said on Thursday. Videos shared on X showed waterlogged roads, causing a problem for the locals. Imagine calling yourself a smart IT City and this is the condition in just a few minutes of rain. 🤦🏻Video from Pune Maharastra which has a 4 engine BJP Govt. MP, MLA, MLCs, Mayor all belong to BJP. — Roshan Rai (@RoshanKrRaii) June 19, 2025 The India Meteorological Department (IMD) has predicted that Pune will experience cloudy skies with moderate rain on June 21. Daytime temperatures are expected to be around 29 degrees Celsius, while the minimum may drop to 22 degrees Celsius. On June 22, the weather will remain generally cloudy with light rain, and temperatures may rise slightly to 30 degrees Celsius and 23 degrees Celsius. Similar conditions with light rain are likely to continue on June 23 and 24, with partly cloudy skies and temperatures hovering around 29–30 degrees Celsius. According to the IMD, rain is expected to increase from June 25, and continue on June 26. Despite the rainy conditions, the IMD has not issued any weather warnings for the coming days. Weather Forecast For Other Places According to the India Meteorological Department (IMD), the southwest monsoon has made further progress, covering the remaining areas of Bihar, eastern Uttar Pradesh, and Madhya Pradesh. It has also advanced into certain parts of western Uttar Pradesh, a large portion of Uttarakhand, several regions of Himachal Pradesh, and some areas of Ladakh. First Published: