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The Wire
a day ago
- Climate
- The Wire
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.'
Time of India
11-06-2025
- Climate
- Time of India
Sizzling day, warm night as Gurgaon records season's hottest day
Gurgaon: The city woke up to a sweltering Tuesday as the maximum temperature rose to 42.8 degrees Celsius, which was 0.3 degrees higher than the previous day, making it the hottest day of the season. The minimum temperature was recorded at 29°C, a 0.8°C rise from Monday. The India Meteorological Department (IMD) has issued a yellow alert for a heatwave and warm night conditions across south Haryana, including Gurgaon, till June 12. "The dry spell is likely to persist for the next four days, with only isolated light rain anticipated. Heatwave conditions are expected to affect isolated pockets of the state from June 9 to 12. Additionally, warm night conditions may prevail in some areas during this period. From June 13 to 15, isolated places may witness thunderstorms, lightning and gusty winds with speeds reaching 40–50 kmph," said an IMD official. Somika Sharma, a resident of Sector 31, said, "It felt like stepping into an oven this morning. I couldn't send my kids to the park because it was just too hot. We are used to summer heat, but this is something entirely different. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Düsseldorf: GEERS sucht 700 Testhörer für Hörgeräte ohne Zuzahlung GEERS Undo It is exhausting just being outside for a few minutes." Amit Khurana, who drives an auto-rickshaw, said, "It's tough to work in this kind of heat. I carry extra water bottles and try to take breaks in the shade. But the roads feel like they're on fire and the hot winds make it worse. We need more public water points and rest areas." Health officials have advised people to stay hydrated, avoid outdoor activities between 12pm and 4pm, and wear light clothes. Children, the elderly and those with health conditions have been advised to remain indoors during the hottest parts of the day. Authorities are closely monitoring the weather conditions and have urged the public to follow heatwave advisories to prevent heat-related illnesses. Dr Vishwas Chitale, senior programme lead at CEEW, said, "A major part of north India, including Delhi, is currently experiencing heatwave conditions with an orange alert issued for June 10 and 11, and a yellow alert issued for June 12. According to the Heat Risk Index published by CEEW, Delhi ranks among the top 10 states and UTs in India, with 55 per cent of its districts falling in the very high-risk category and the remaining in the high-risk category. The north Indian region, which witnesses 40°C plus temperatures during the day, has shown an increase in relative humidity (about 6-9%) in the past decade. This, compounded with an increase in the very warm nights during the summers (six additional warm nights per summer were observed in Delhi in 2012-2022 compared to 1982-2011), increases the heat risk faced by the vulnerable population of the region. When heat and humidity are combined, the felt heat can be, on average, 3-5°C more than dry heat. Delhi govt's newly launched Heat Action Plan marks a crucial step towards addressing both immediate threats and long-term resilience." Meanwhile, Delhi experienced the warmest day of the year as the temperature soared marginally, bringing more areas of the national capital under the grip of a heatwave. The heat index, or "feel-like" temperature, was recorded at 47.7 degrees Celsius due to low humidity. The Met has, however, forecast that the extreme heat will persist on Wednesday, issuing an orange alert for the heatwave. "Heat wave conditions reported over Delhi—Lodhi Road, Ridge, Ayanagar with the highest maximum of 45.5 degrees Celsius over Ayanagar," said Krishna Mishra, weather scientist at IMD. He added that the impact of the heatwave extended by Tuesday, with severe heatwaves in Jammu and Kashmir and many parts of Himachal Pradesh as well. The maximum temperature at the city base station was recorded at 43.8 degrees Celsius, four notches above normal, making Tuesday the warmest day of the year. The maximum temperature a day earlier was 43.4 degrees Celsius, which is now the second highest. Earlier on May 16, the maximum temperature reached 42.3 degrees Celsius, now the third highest. The humidity also reduced due to more dry and warm westerly winds, oscillating between 24% and 48%. According to IMD forecast, heatwave conditions will persist through Wednesday, with relief anticipated from Friday due to potential increased moisture levels in the region, which could bring thunderstorms and rainfall. Among other hot areas of the city, Ayanagar recorded 45.5 degrees Celsius, Ridge recorded 45 degrees Celsius, Palam recorded 44.6 degrees Celsius, Pitampura recorded 44.8 degrees Celsius, and Lodhi Road recorded 43.6 degrees Celsius, respectively. By the norms of IMD, a heatwave in plain areas is declared when the maximum temperature is either 45 degrees Celsius or above, or when it's above 40 degrees Celsius with a departure above 4.5 notches above normal. By this definition, three city areas, including Lodhi Road (departure 4.6 notches), suffered a heatwave. The Met department has forecast a heatwave warning until Wednesday, expecting the maximum temperature to hover around 44 to 46 degrees Celsius.
San Francisco Chronicle
28-05-2025
- Climate
- San Francisco Chronicle
Why California's coming heat wave could be more dangerous than you think
The Bay Area is heading into its first heat event of the season and it's arriving abruptly. A heat advisory is in effect for California's interior Friday and Saturday, including parts of the East Bay, North Bay and South Bay. It comes as a strong area of high pressure builds over the West, triggering a sharp temperature spike that could push some Central Valley cities toward record highs for May. In the Bay Area, it's not just the peak temperatures that make this heat event notable, it's how quickly they arrive. In places like Livermore, highs are expected to jump from the low to mid-80s on Thursday to triple digits by Friday: that's an almost 20-degree spike in just 24 hours. This kind of surge would rank among the most abrupt single-day warmups the region has seen in the last quarter century. The South Bay will see a similar surge. San Jose is forecast to rise from the low 80s on Thursday to the upper 90s by Friday, a 13- to 15-degree spike in one day. That would rank among the sharpest single-day warmups in the past 25 years. The jump will be a bit less dramatic in the North Bay, where hotter spots like Santa Rosa and Napa are expected to climb about 10 degrees, from around 90 on Thursday to near 100 by Friday. What makes the heat even more striking is how unremarkable things have been until now. Most of the Bay Area's inland cities have cruised through May with average highs, warm, but far from hot. San Jose hasn't cracked 90 degrees yet this year; Livermore's and Santa Rosa only did it once. For much of the region, this week marks the first true taste of summer heat. With temperatures ramping up quickly, it's the kind of shift that can catch people off guard. Our bodies need time to adjust to extreme heat, and most of us simply aren't acclimated to triple-digit temperatures yet. That's part of what makes early-season heat especially risky. The National Weather Service's Heat Risk Index notes that first heat events of the year tend to carry higher health risks across all demographics, even for otherwise healthy individuals. Wednesday breakdown San Francisco: A deep and persistent marine layer will blanket much of the city in the morning, potentially producing pockets of drizzle. Partial afternoon sun may break through, but it'll be a chilly day overall. Highs will reach the upper 50s in the Outer Sunset and Richmond and the low 60s downtown, with a steady west wind at 10 to 20 mph. Clouds return overnight with lows around 50 degrees. North Bay: The marine layer will penetrate deeper into the North Bay valleys in the morning, eventually retreating to the immediate Marin coastline. The rest of the day will be mostly sunny but cool. Highs will be in the upper 60s in Vallejo, the low 70s in San Rafael and Petaluma and the upper 70s to around 80 degrees in Santa Rosa and Vacaville. Winds from the west will funnel through the valleys at 10 to 25 mph. Partly cloudy skies overnight with lows in the 50s. East Bay: Marine layer clouds will linger west of the Berkeley Hills through much of the morning, with drizzle possible in the hills. It'll be sunny inland, with sunshine gradually pushing toward the bay shore by afternoon. Highs will reach the upper 60s in Richmond and Oakland, and the low to mid-70s in Hayward, Concord and Livermore. A stiff westerly breeze will kick up along the bay shore, with gusts up to 25 mph. Overnight, clouds return to the water, while inland areas stay mostly clear with lows in the low 50s. Pacific Coast and Peninsula: Patchy drizzle and low clouds will dominate the morning hours along the coast, especially in Pacifica and Half Moon Bay, where highs will stay stuck in the upper 50s. A bit of sun may peek through in the afternoon, but don't expect much clearing along Highway 1. Daly City and Redwood City should see partial afternoon sunshine, with highs ranging from the low 60s to around 70 degrees. West winds will gust up to 25 mph in the afternoon. Overnight, clouds and patchy drizzle return to the coast, with lows in the low 50s. South Bay and Santa Cruz: Morning clouds will give way to sunshine across the South Bay, with highs in the upper 60s in Mountain View, low 70s in San Jose, and upper 70s in Gilroy. Santa Cruz starts off gray with patchy drizzle, but skies clear by midday, with highs in the low to mid-70s. The Santa Cruz Mountains will stay cooler, topping out in the 60s to low 70s. Winds will pick up out of the northwest at 10 to 20 mph by afternoon. Overnight, patchy drizzle may return to the coast, with lows in the upper 40s to low 50s.
Time of India
24-05-2025
- Climate
- Time of India
Kol, 5 Bengal dists at ‘high risk' for extreme heat: Study
1 2 Kolkata: Kolkata is among six Bengal districts flagged as "high-risk" for extreme heat in a nationwide heat risk assessment by the Council on Energy, Environment and Water (CEEW). The report titled 'How Extreme Heat Is Impacting India: Assessing District-level Heat Risk' presents the first composite Heat Risk Index (HRI) for all 734 districts in India. Significantly, the six Bengal districts do not have a heat action plan to help citizens adapt to the problem. While Bengal is 15th among states on the HRI, indicating a moderate overall risk, Kolkata, North 24 Parganas, South 24 Parganas, Purulia, East Midnapore and Bankura feature among the 417 districts in India under the high and very high risk category. Unlike in the past, heat stress is not fading in the city with sunset, says the report. Very warm nights and rising humidity are reducing the body's ability to recover from daytime heat, posing serious health risks, especially for the elderly, children, outdoor workers, and people with chronic illnesses. "Heat stress is no longer a future threat — it's a present reality," said Arunabha Ghosh, CEO of CEEW. "We are entering an era of intense, prolonged heat and dangerously warm nights. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Trade Bitcoin & Ethereum – No Wallet Needed! IC Markets Start Now Undo It's time to overhaul our heat action strategies with district-specific solutions," he added. As many as 12 Bengal districts came under the moderate risk category on the list, while northern districts like Darjeeling, Kalimpong and Jalpaiguri have been considered low-risk. Cooch Behar and Alipurduar are the only districts in the very low-risk category. The study arrives at a time when 57% of India's districts — home to over 76% of the population — are at risk due to extreme heat. Many cities across India, including Delhi, Mumbai, and Hyderabad, are experiencing increased vulnerability due to urban heat islands and dense populations. To build a momentum for nationwide heat resilience, CEEW launched the report and deliberated on practical strategies for heat action planning, disaster risk reduction, and financing for sustainable cooling. "The urban heat island and shrinking green space have been exacerbating the problem," said Vishwas Chitale, who leads the climate resilience team at CEEW. The report underscores the importance of moving beyond daytime heat metrics. It calls for an urgent update of heat action plans to include measures for night-time heat and rising humidity, especially as the State Disaster Mitigation Fund now recognises heatwaves as a disaster eligible for relief funding. CEEW is also showcasing affordable and scalable heat adaptation strategies such as cool roofs, net-zero cooling shelters, emergency heat stroke rooms and parametric heat insurance. Get the latest lifestyle updates on Times of India, along with Brother's Day wishes , messages and quotes !
Time of India
24-05-2025
- Climate
- Time of India
Kolkata, 5 more Bengal districts at 'high risk' for extreme heat, says study
KOLKATA: Kolkata is among six Bengal districts flagged as "high-risk" for extreme heat in a nationwide heat risk assessment by the Council on Energy, Environment and Water (CEEW). The report titled 'How Extreme Heat Is Impacting India: Assessing District-level Heat Risk' presents the first composite Heat Risk Index (HRI) for all 734 districts in India. Significantly, the six Bengal districts do not have a heat action plan to help citizens adapt to the problem. While Bengal is 15th among states on the HRI, indicating a moderate overall risk, Kolkata, North 24 Parganas, South 24 Parganas, Purulia, East Midnapore and Bankura feature among the 417 districts in India under high and very high risk category. Unlike in the past, heat stress is not fading in the city with sunset, says the report. Very warm nights and rising humidity are reducing the body's ability to recover from daytime heat, posing serious health risks, especially for the elderly, children, outdoor workers, and people with chronic illnesses. "Heat stress is no longer a future threat - it's a present reality," said Arunabha Ghosh, CEO of CEEW. "We are entering an era of intense, prolonged heat and dangerously warm nights. It's time to overhaul our heat action strategies with district-specific solutions," he added. Get the latest lifestyle updates on Times of India, along with Brother's Day wishes , messages and quotes !
