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CSE report urges comprehensive plan to clean Yamuna river

The Centre for Science and Environment released an agenda report on cleaning the Yamuna in Delhi on Thursday. It suggests that the authorities accept the reality of missing data, reset the current plan and explore a different approach, including curbing the contamination of the Najafgarh and Shahdara drains. Sunita Narain, director general, CSE, pointed out that while the 22km stretch of the Yamuna in Delhi was merely 2 per cent of the total river, this portion accounted for 80 per cent of the pollution in the river. Though she appreciated the attention the Yamuna was getting, including of the Prime Minister, Narain noted several lacunae in the current plan. She said that while there were 22 drains with outfalls in the river, the Najafgarh and Shahdara drains were responsible for 84 per cent of the total pollution in Delhi.

Reset the action agenda for cleaning the Yamuna in Delhi-NCR — says CSE

In the four years between 2017 and 2022, the Delhi government spent more than Rs 6,856 crore on cleaning the Yamuna. Delhi now has 37 sewage treatment plants with a capacity to treat over 80-100 per cent of the generated sewage, and almost 80 per cent of the city is connected to sewer lines. In spite of all this, why does the Yamuna continue to run polluted and unclean? A new assessment by Centre for Science and Environment (CSE), released here today at a press briefing, attempts to unravel this mystery and offer an action plan that will work. Yamuna: The Agenda for Cleaning the River – as the assessment report is titled – says: “The 22-km stretch of the Yamuna in Delhi, barely 2 per cent of the total length of the river basin, contributes over 80 per cent of the pollution load in the entire river. There is no water in the river for almost nine months in a year – what flows in it is just sewage and waste from Delhi’s 22 drains. The Yamuna ceases to exist after it enters Delhi at Wazirabad.” Speaking at the press briefing, CSE director general Sunita Narain said: “The problem of cleaning the Yamuna is not a new one; huge amounts of money have been spent over the years, plans have been initiated and carried out. The agenda for cleaning the river is critical as a ‘dead Yamuna’ is not just a matter of shame for the city and for us – it also adds to the burden of providing clean water to Delhi as well as to the cities downstream.”

84 प्रतिशत प्रदूषण के लिए नजफगढ़ और शाहदरा नाले जिम्मेदार

राजधानी दिल्ली में यमुना नदी के प्रदूषण के प्रमुख कारणों में नजफगढ़ और शाहदरा नाले का प्रमुख योगदान है। पर्यावरण एवं विज्ञान केन्द्र (सीएसई) की गुरुवार को जारी रिपोर्ट में यह जानकारी सामने आई। रिपोर्ट के अनुसार, ये दोनों नाले यमुना में 84 प्रतिशत तक प्रदूषण के लिए जिम्मेदार हैं। सीएसई की महानिदेशक सुनीता नारायण ने कहा कि यमुना की सफाई के लिए दिल्ली सरकार ने 2017 से 2022 तक 6856 करोड़ रुपये खर्च किए हैं, फिर भी प्रदूषण की स्थिति में कोई विशेष सुधार नहीं हुआ। रिपोर्ट में यह भी बताया गया कि दिल्ली के 22 किलोमीटर के यमुना हिस्से का प्रदूषण पूरे नदी के प्रदूषण का 80 प्रतिशत योगदान देता है, हालांकि यह हिस्सा नदी की कुल लंबाई का मात्र दो प्रतिशत है। सीएसई की रिपोर्ट के अनुसार, इस हिस्से के प्रदूषण में प्रमुख कारण नालों का गंदा पानी है, जिसे नदियों में छोड़ा जा रहा है। मल-मूत्र टैंकरों की निगरानी रिपोर्ट में यह भी उजागर हुआ है कि दिल्ली में जहां सीवर लाइन नहीं हैं, वहां सेप्टेज टैंक से मल-मूत्र को टैंकरों द्वारा नाले में गिरा दिया जाता है। सीएसई ने इस पर सुझाव दिया है कि इन टैंकरों पर जीपीएस लगा कर उन्हें निगरानी में रखा जाए, ताकि प्रदूषित जल को सही तरीके से उपचारित किया जा सके। उपचारित पानी का सही उपयोग सीएसई ने यह भी बताया कि सीवेज ट्रीटमेंट प्लांट से उपचारित पानी का सही तरीके से उपयोग नहीं किया जा रहा है। इस पानी को नालों में छोड़ा जा रहा है, जबकि इसे सीधे यमुना में डालने से नदी की स्थिति में सुधार हो सकता है।

Feel the burn: The nature of the heat we face is changing. What should you expect this summer?

Have you stepped out of a cooled car recently and felt like your clothes were on fire? This is the result of what meteorologists call “oppressive” heat: high temperatures paired with high humidity. An oppressive heatwave is a step up, in intensity, from an extreme heatwave, says Subhankar Karmakar, a professor with the Environmental Science and Engineering Department and the Centre for Climate Studies at the Indian Institute of Technology-Bombay (IIT-B). As we know by now, when humidity rises, it makes it harder for the human body to cool — because sweat cannot evaporate as easily. “Extreme heatwave conditions are uncomfortable and dangerous, but at least there’s the opportunity for sweat to cool the human body, since humidity isn’t high,” Karmakar says. “Oppressive heatwaves can quickly turn fatal. They have a higher correlation with heat-stress-related deaths.” According to 2024 data from the think-tank Centre for Science and Environment (CSE), five of India’s six megacities (barring Bengaluru) have seen average relative humidity in summer (March-August) rise by 5% to 10%. That’s across Delhi, Kolkata, Mumbai, Chennai and Hyderabad. Over the last 13 summers, Hyderabad has been 10% more humid on average than it was in 2001-10. Delhi has been 8% more humid. Mumbai, 7%, and Kolkata and Chennai 5% more humid on average. Interestingly, both Delhi and Hyderabad are in some of the driest climatic zones in India. Where, then, is the moisture coming from? How much of it has to do with our activity, the fallout of urban heat islands, and even air-conditioning directly? Read on for more on this. A family at a misting spot in China, amid the 2022 heatwave. (Getty Images) A family at a misting spot in China, amid the 2022 heatwave. (Getty Images) Meanwhile, back at IIT-B, Karmakar, working alongside professor Subimal Ghosh and doctoral researchers Naveen Sudharsan and Anokha Shilin, is in the process of tallying actual oppressive heatwave days in India. The number of such days is rising, driven by rising temperatures and delayed or weak monsoons and by the density of urbanisation and shrinking green spaces, Karmakar says. Preliminary results suggest that oppressive heatwaves are expanding both in frequency and geographic extent across the country — and these trends are projected to worsen as global temperatures approach and exceed 1.5°C above pre-industrial levels. (A marker that, by some accounts, has already been crossed.) Getting word out There’s an issue with talking about the dangers of heat. Too much of the time, no one’s buying it. Between an overwhelming sense that “we’ve dealt with this before” and the idea of a warm day as a good thing (torrential rain is a problem; ice and snow are problems; what’s a little heat, right?), governments are hitting literal red alert in efforts to be heard. In India, heatwaves have been colour-coded since 2017, based on the action required: green is a normal day (no action required); yellow is tolerable (but a point of concern for vulnerable populations such as seniors and people with comorbidities); orange is severe (avoid exposure, stay cool, hydrate); and red is extreme (be very cautious, venture outdoors only if you must). Yellow, orange and red alerts typically come with cautionary messages, particularly for vulnerable populations.But the alerts only go out from the India Meteorological Department (IMD) to arms of the government. It is up to the media and local governing bodies to take the message to the people. In Europe, where a heatwave in 2003 killed 70,000 — nearly 15,000 of those in France alone — some governments are no longer waiting for this kind of multi-link chain to take effect. France has a government-run heat map app that pings if the users are in a high-temperature zone, and can tell them what to do to stay safe, and guide them to the nearest “cool island”. Seville in Spain and Athens in Greece have started naming and ranking heatwaves so people have a clearer sense of how serious each one is, and so that a graded emergency response can follow. Weather bureaus in these cities consider air temperature as well as humidity, sea-level pressure, cloud cover, solar radiation and wind speed, among other factors, when assigning these grades. Seville is naming heatwaves too, in an effort to make the threat as real as it would be with, say, a hurricane. The US National Oceanic and Atmospheric Administration (NOAA) also factors in heat, relative humidity and wind speed, when announcing heatwaves in the US. IMD, in a significant drawback, still relies only on temperature. It declares a heatwave when the maximum temperature at a weather station reaches 40 degrees Celsius in the plains, 37 degrees Celsius at the coasts, and 30 degrees Celsius in hilly regions and stays at least 4.5 degrees Celsius above normal for two consecutive days. “In India, we are still primarily focusing on extreme temperature thresholds, rather than explicitly incorporating humidity-driven heat stress,” Karmakar says. “So, we’re potentially underestimating heat risks.” Construction workers in Gurugram. We don’t know the true toll of our heatwaves. ‘Many deaths occur outside the formal medical system, particularly among outdoor workers, the homeless and rural communities,’ says Apekshita Varshney, founder of the NGO HeatWatch. (HT Archives) Construction workers in Gurugram. We don’t know the true toll of our heatwaves. ‘Many deaths occur outside the formal medical system, particularly among outdoor workers, the homeless and rural communities,’ says Apekshita Varshney, founder of the NGO HeatWatch. (HT Archives) Night sweats Meanwhile, partly because of the rising humidity levels, our megacities aren’t cooling; not even at night. All six megacities — Delhi, Mumbai, Bengaluru, Kolkata, Chennai and Hyderabad — have recorded a rise in nighttime relative humidity in summer, nullifying the fall in air temperatures in certain areas, notes the 2024 report by CSE. “A web of climatic, urban and anthropogenic factors are contributing to the rise of relative humidity across our cities,” says Sharanjeet Kaur, programme officer at CSE and co-author of the report. “Rapid urbanisation and the expansion of built-up areas contribute significantly to heat retention, triggering the urban heat island effect (UHI). The UHI, in turn, intensifies local humidity levels — because warm air can hold more moisture; cool air reaches a saturation point faster. Additionally, cooling systems such as ACs and cooling towers release both heat and moisture into the surrounding atmosphere, intensifying this effect.” The situation is compounded by dense infrastructure, which restricts natural ventilation and limits the dispersion of moisture. “The increase in built-up area has altered the natural thermal balance,” Kaur says. “Concrete and asphalt also absorb heat more during the day than earth, and release it slowly at night, contributing to persistently high nighttime temperatures.” How bad is it? Where Delhi’s summer nighttime temperatures typically fell by 12.31 degrees Celsius between 2001 and 2010, they have fallen by an average of 11.2 degrees Celsius since 2014. Mumbai nighttime temperatures typically fell by 10.22 degrees Celsius between 2001 and 2010, and have fallen by about 7.8 degrees Celsius since 2014. In Bengaluru and Chennai, there was generally an 11.90 degrees Celsius and 10.17 degrees Celsius fall respectively. Now, the drop stands at 10.1 degrees Celsius and 9.7 degrees Celsius respectively, on average. “People get little chance to recover from daytime heat slaughter if temperatures remain high overnight, exerting prolonged stress on the body,” the study notes. The same is true for plants, birds and animals. Without adequate cooling at night, they too struggle to recover, leading to greater heat stress over time, and a weakening of systems. This can range from higher respiration rates, poor growth and reduced yields in flora, to altered behaviours and disruptions in migration patterns in fauna. We don’t know the toll India’s data-gathering systems haven’t fully caught up to the problem. Between March and July 2024, for instance, India reported 48,156 suspected cases of heat stroke, 269 suspected deaths and 161 confirmed deaths, says a December 2024 report released by the National Programme on Climate Change & Human Health (NPCCHH). HeatWatch, an Indian non-profit organisation, found that across 17 states, there were at least 733 confirmed deaths within the same timeframe. The government data needs improvement, in terms of coverage, says HeatWatch founder Apekshita Varshney. On average, 55% of public health facilities submitted data on cases of heat distress and death in 2024, up from 23% in 2023, according to the NPCCHH report. Clearly, gaps remain and that means we do not know the true toll of this threat. In the most glaring instance of missing data, “many deaths occur outside the formal medical system, particularly among outdoor workers, the homeless and rural communities,” Varshney says. “There’s also a lack of standardisation when it comes to identifying, categorising and confirming heatstroke and heat-related deaths.” We need to update our definitions The National Disaster Management Act of 2005 does not currently classify heatwaves as a notified disaster. This will need to change, to unlock more funding for mitigation and relief efforts (the kinds of efforts we currently see with notified disasters such as floods and cyclones). Certain states — Tamil Nadu, Odisha, Kerala, Uttar Pradesh and Telangana — have notified heatwaves as a disaster at the state level. But NDMA notification alone won’t be enough, Varshney says. “There needs to be a better, clearer blueprint of coordination between state officials, municipalities, district administrations and health departments, before, during and after heatwave conditions.” For now, the very definition of a heatwave in India is holding things back. In addition to accounting only for heat — not even for humidity — the IMD parameters of 40 degrees Celsius for the plains, 37 degrees Celsius for the coasts and 30 degrees Celsius for the hills are too narrow. “We need to start accounting for a wider range of local thresholds, and for changes from historic temperature and humidity levels,” says Karmakar of IIT-B. Across most of India, dangerous heat begins well before official thresholds are crossed, he adds. Our current view on heat continues to misrepresent this, leaving vulnerable populations —including outdoor workers, the urban poor, children, the elderly and people with comorbidities — exposed, unprotected and perhaps most vitally, uninformed. Data and definitions are all very well. What else can we do? Nine Indian cities — Delhi, Mumbai, Bengaluru, Kota, Ludhiana, Meerut, Faridabad, Gwalior and Surat — are likely to face the sharpest immediate spikes in heat, indicates a study conducted by the independent research organisation Sustainable Futures Collaborative (SFC). All nine cities are reportedly working on short-term emergency measures, but not adequately on long-term ones. The former include access to drinking water, staggering or changing work schedules, boosting hospital capacity, setting up cooling centres, sprinkling water on roads, and distributing oral rehydration solution (ORS) packs. What’s missing? Long-term measures — such as making cooling systems more easily available; developing an insurance plan for work days and daily wages lost to heat stress; expanding fire management services; retrofitting electricity grids to maintain distribution — are either missing or poorly targeted, the report states. “Expansion of local weather stations for more granular data on heat variation within a city, mapping urban heat islands, and training heat plan implementers were only seen in some cities. Other actions like expansion of urban shade and green cover, the creation of open spaces that dissipate heat, and the deployment of rooftop solar that could help with active cooling, among others, were implemented without adequate attention to populations and areas that experience the greatest heat risk,” the authors note. What’s holding us back? One of the biggest roadblocks is inter-departmental coordination, says Tamanna Dalal, a senior research associate at SFC and co-author of the nine-cities study. For instance, in some cases, the disaster management department is the nodal agency; in others, it is the health department. “Neither has any real power to coordinate action between departments. Meanwhile, some departments, such as urban development, who are responsible for certain areas of heat-mitigation action, aren’t made part of the conversation at all,” Dalal says. Worse still, “heat is seen as a second-order priority or not at all,” she adds. “For instance, even within the health departments in these cities, malaria or dengue might be the top priority during summer, rather than heat.” Within the bureaucratic imagination, heat lies in a tricky space, adds Aditya Valiathan Pillai, a visiting fellow at SFC, a PhD researcher at King’s College London, and lead author on the study. “It’s still a nascent policy area. It doesn’t have firm institutional, legal or financial backing.” The study recommends strengthening heat action plans with more funding, training and institutional backing. It is also time for the government to begin to subsidise cooling equipment, Pillai says. “While air-conditioning isn’t a long-term fix, it can help. Subsidised AC-buying programmes, like the government Ujala programme for LED lights, could help promote less-power-intensive and cost-intensive solutions. Most of India’s lower-middle-class and poor are currently buying power-guzzling second-hand ACs or poor-quality coolers. They can’t afford the power these machines guzzle, and this kind of equipment isn’t good for the grid either.” Is it a given, then, that most of us will need cooling equipment, at least during part of the year? “Unfortunately, yes, yes it is,” he says.

ANTIBIOTIC USE IN POULTRY: CROSSROADS OF RESISTANCE, PUBLIC HEALTH, AND POLICY GAPS

ABSTRACT In this paper explore about antibiotic impact on chicken, mechanism of antimicrobial resistance, antibiotic impact on poultry worker while using antibiotic in animal for therapeutic and non therapeutic, antibiotic impact on human through environment and animal food, antibiotic impact on children enter through the animal food and vegetables from infected soil and impact of antibiotic to cause cancer. Over the half century almost all known antibiotics are increasingly losing their activity against pathogenic microorganisms. In worldwide more than 60 % of all antibiotics that are used in animal production for both therapeutic (Prophylaxis) an non therapeutic (growth promoters) purposes. Furthermore, antibiotics are widely used to prevent bacterial diseases in plants also. Adequate cooking generally destroy the pathogenic bacteria in food, if hygiene measures are inadequate in food outlets, and it may be that such cross-contamination occurs with other bacteria as well, including resistant strains, but again there is no direct information. In particular, with overuse or prolonged exposure of main antibiotic classes associated with an excess of incident cancer. Antibiotic impact on chicken Poultry is defined as a group of domesticated birds raised for animal products (e. g., meat, eggs, manure), fiber (e. g., feathers), entertainment (e. g., racing, exhibition, hunting, etc.), CSE study conducted in chicken sample for Growing antibiotic-resistance in humans also because of large-scale indiscriminate use of antibiotics in poultry industry Indians are developing resistance to antibiotics — and hence falling prey to a host of otherwise curable ailments. Some of this resistance might be due to large-scale unregulated use of antibiotics in the poultry industry, says a new study released here today by Centre for Science and Environment (CSE), the New Delhi-based research and advocacy think-tank. Releasing the findings of the study which has been conducted by CSE‘s Pollution Monitoring Laboratory (PML), Sunita Narain, director general, CSE, said: ―Antibiotics are no more restricted to humans nor limited to treating diseases. The poultry industry, for instance, uses antibiotics as a growth promoter. Chickens are fed antibiotics so that they gain weight and grow faster. ‖ The CSE lab study found residues of antibiotics in 40 per cent of the samples of chicken that were tested.

Delhi's Yamuna-cleaning plan needs reset, not just money: Report

New Delhi, Amid renewed efforts to clean the Yamuna in Delhi, a new analysis released on Thursday said authorities need to rethink their strategy and stop the mixing of treated and untreated water in drains flowing into the river. The analysis by Delhi-based think tank Centre for Science and Environment said officials must ensure that tankers collecting faecal sludge from areas without sewer connections do not dump it into drains or the river. CSE director general Sunita Narain said all such tankers should be fitted with GPS trackers to make sure the sludge is taken to sewage treatment plants for proper treatment and reuse. She added that untreated water from unsewered areas should be treated near the river before being released. Narain also said that one of the biggest problems in cleaning the Yamuna is the lack of clear data on the city's population, which makes it difficult to know if the current treatment capacity is sufficient. The 22-kilometre stretch of the Yamuna between Wazirabad and Okhla in Delhi, less than 2 per cent of the river's total length, accounts for 80 per cent of its pollution load.

Delhi's Yamuna-cleaning plan needs reset, not just money: Report

Amid renewed efforts to clean the Yamuna in Delhi, a new analysis released on Thursday said authorities need to rethink their strategy and stop the mixing of treated and untreated water in drains flowing into the river. The analysis by Delhi-based think tank Centre for Science and Environment (CSE) said officials must ensure that tankers collecting faecal sludge from areas without sewer connections do not dump it into drains or the river. CSE director general Sunita Narain said all such tankers should be fitted with GPS trackers to make sure the sludge is taken to sewage treatment plants (STPs) for proper treatment and reuse.

Artificial rain, crackdown on aged vehicles under Delhi govt’s air action plan

Chief minister Rekha Gupta on Tuesday chaired a high-level review meeting on Delhi’s Environment Action Plan 2025-26, where she announced a series of steps to improve the air quality, including mandatory rooftop sprinkler systems in all high-rise buildings and compulsory water sprinkling systems at construction sites to tackle dust pollution. The CM also announced that the government will deploy 1,000 water sprinklers and 140 mobile anti-smog guns to suppress dust in the city throughout the year barring the monsoon season. The review meeting was held with environment minister Manjinder Singh Sirsa and senior officials from the environment department, Commission for Air Quality Management (CAQM) and other departments concerned. All departments were instructed to undertake strict and timebound measures to combat pollution, officials said. Referring to vehicular pollution and end-of-life vehicles (ELVs) -- 10-year-old diesel and 15-year-old petrol vehicles – the CM said the government has already installed 495 Automatic Number Plate Recognition (ANPR) cameras at petrol stations. The cameras will also be put up at Delhi’s border points, she said. “These cameras will identify restricted vehicles and notify authorities for enforcement. Also, this system will allow real-time tracking of ELVs plying within the city,” Gupta said after the meeting. “If any ELV enters Delhi, the owner will receive an instant SMS alert. Signboards at border points will also display the count of such vehicles,” she added. Besides, the government will undertake an audit of all Pollution Under Control (PUC) centres. Any PUC centre found issuing false certificates will face heavy fines, the CM said. The government will also make mandatory registration of construction and demolition (C&D) sites over 500sqms in area through the Delhi Pollution Control Committee (DPCC)’s web portal. “This will ensure compliance with air pollution control norms at large sites. Additionally, sites between 200–500sqms must also follow dust control guidelines, with MCD responsible for enforcement,” the CM said. For green last-mile connectivity, Gupta said 2,300 e-rickshaws will be stationed at metro stations, out of which 700 will be operated by women. The government also plans to pursue its ambitious plan of carrying out cloud seeding to induce rain, as it is preparing to conduct a trial soon. The CM said a Memorandum of Understanding (MoU) will soon be signed with IIT-Kanpur for this purpose. Sirsa said the plan also covers removal of the garbage mountains. “A key feature of this environment action plan is the development of an AI-enabled beta version of the DPCC portal, which will enable direct online issuance of challans to polluting entities. Additionally, the vehicles carrying anti-smog guns and water/mist sprinklers will be GPS-enabled for effective real-time monitoring,” said the minister. Experts welcomes the measures but emphasised that more action is needed to control emissions at their source. “These are strategies and actions largely to control dust, or enforcement measures. However, to improve Delhi’s air quality, we also need to control emission at sources and need a systemic and infrastructural-level plan to upscale solutions that are sustainable,” said Anumita Roychowdhury, executive director, research and advocacy at the Centre for Science and Environment (CSE).

सुनीता नारायण का कॉलम:पर्यावरण को ध्यान में रखकर भी हम विकास कर सकते हैं

भारत को जलवायु परिवर्तन से निपटने के लिए कोई कदम नहीं उठाना चाहिए- जब ​मैंने विभिन्न यूरोपीय देशों के जलवायु परिवर्तन दूतों के एक समूह से यह बात कही तो उनके चेहरों पर असमंजस के भाव थे। मैंने उन्हें अपने कारण बताए। विकास भारत जैसे देश के लिए बड़ी चुनौती है। यह विकास समावेशी और टिकाऊ भी होना चाहिए। अगर हम इसे हासिल करते हैं, तो हम एक बेहतरीन लक्ष्य पर पहुंच जाएंगे- स्थानीय प्रदूषण को कम करने और ग्रीन-आजीविका को बढ़ावा देने के लिए हमारे कदम ग्रीनहाउस गैस उत्सर्जन को भी कम करेंगे। इस तरह, हमारा राष्ट्रीय स्तर पर निर्धारित योगदान (एनडीसी) पारस्परिक-लाभों पर आधारित होगा। दूसरे शब्दों में अगर सही तरीके से विकास किया जाए, तो वह जलवायु परिवर्तन के संकट का भी सामना कर सकता है। दुनिया के दूसरे तमाम देशों की तरह भारत को भी विकास करना है। इसका मतलब है लाखों लोगों को रोजगार देना, उन्हें स्वास्थ्य सेवा, शिक्षा और आवास प्रदान करना और ऊर्जा आपूर्ति को बढ़ाना। विकास के लिए हमें ऐसी कार्रवाई की आवश्यकता होगी, जो सभी की जरूरतों को पूरा करे। इसके लिए रणनीति में बदलाव की जरूरत है। हम पूंजी और संसाधनों की प्रचुरता वाले मार्ग का जोखिम नहीं उठा सकते, क्योकि वह पर्यावरण को नुकसान पहुंचाता है और समाज में भी ​असमानता को बढ़ाता है। हम पहले प्रदूषण फैलाने और फिर उसकी सफाई करने के पश्चिमी देशों के दृष्टिकोण को नहीं अपना सकते। हमारे पास नुकसान की मरम्मत के लिए वित्तीय साधन भी नहीं हैं। ऐसे में हमें विकास की अपनी अवधारणा को फिर से आविष्कृत करना होगा और भारत में कई नीतियों ने यही किया है। यह भारत जैसे देशों के लिए अनूठा अवसर है कि वह विकास को जलवायु-कार्रवाई के खिलाफ खड़ा करने के बजाय उसे विकास के लिए बनाई गई नीतियों के भीतर समाहित कर सके। उदाहरण के लिए, हम जानते हैं कि हम अपनी मोबिलिटी के तौर-तरीकों को बदले बिना वायु प्रदूषण को ठीक नहीं कर सकते, क्योंकि निजी वाहन- वो चाहे जितने भी स्वच्छ क्यों न हों- सड़क की जगह घेरते हैं और प्रदूषण और भीड़भाड़ को बढ़ाते हैं। पश्चिम ने निजी वाहनों को सब्सिडी देने और उनका विद्युतीकरण करने का रास्ता अपनाया है। हमारे पास एक और उपाय है, जो हमारे आवागमन को फिर से परिभाषित करता है। यह है इलेक्ट्रिक बसों और पैराट्रांजिट और दोपहिया वाहनों जैसे किफायती परिवहन में निवेश करना। भारत का एनडीसी लो-कार्बन वाले सार्वजनिक परिवहन को बढ़ाने के बारे में होना चाहिए, न कि केवल इलेक्ट्रिक कारों की गिनती करने के बारे में। यह नीति हवा को शुद्ध रखने से प्रेरित है, लेकिन इसमें जलवायु परिवर्तन से निपटने का अतिरिक्त लाभ भी है। उद्योग-जगत से एक उदाहरण देखें : हमारे सीमेंट उद्योग ने फ्लाई ऐश का उपयोग करना शुरू कर दिया है- कार्बन को कम करने के लिए नहीं, बल्कि कचरे को कच्चे माल के रूप में इस्तेमाल करने, चूना-पत्थर का विकल्प चुनने और ऊर्जा की लागत कम करने के लिए। लो-कार्बन वाले औद्योगीकरण का भविष्य इसी तरह के समाधानों में निहित है, जिनसे सभी को लाभ हो। जैसे कि लौह अयस्क स्लैग से लेकर बायोमास और कचरे से प्राप्त होने वाले ईंधन तक- ये सभी कोयले और अन्य जीवाश्म ईंधन के उपयोग को कम करने और दक्षता में सुधार के लिए हैं। सबसे महत्वपूर्ण बात यह है कि हमें ग्रीन-इकोनॉमी के विचार को फिर से तैयार करना होगा। हम ग्रीन-एम्प्लॉयमेंट की बातें नहीं कर सकते, क्योंकि हम जानते हैं कि रिन्यूएल ऊर्जा या ईवी को अपनाने का मतलब आजीविका के अधिक अवसर नहीं होगा। वास्तव में, हाल ही में आई खबरों से पता चलता है कि इलेक्ट्रिक आर्क फर्नेस को अपनाने के कारण यूके में हजारों नौकरियां चली गई हैं। लोग अगर जलवायु-परिवर्तन के बारे में चिंतित हैं तो वे अपनी आजीविका के बारे में भी चिंता करते हैं। भारत के लिए जरूरी है वह अपनी अर्थव्यवस्था को ऐसे तैयार करे कि स्थानीय संसाधनों का उपयोग स्थानीय आजीविका के लिए हो। (ये लेखिका के अपने विचार हैं)

Why we need scientists now, more than ever

When we look back at human history, most of our great collective achievements have long-term science at their core. Science has saved us many times from the precipice of disaster and given us breakthroughs that have saved millions of lives and opened new frontiers of possibility. If we want to leave a flourishing future for generations to come, science should consistently be nurtured, celebrated and invested in, not dismissed, undermined and attacked. Recent political moves in the United States and in other nations have severely reduced science budgets and abruptly halted critical research; threatening lives, halting innovation, undermining economies and risking planetary stability. Now is the moment for all of us to speak out. The path forward is not guided by ideology, but by evidence. Facts do not waver under political pressure. Research institutions across the globe stand in solidarity. Together, we must continue to support them, to uphold scientific integrity and the pursuit of solutions grounded in knowledge and collaboration. As a collective, we believe in the importance of science to navigate the planetary emergency. In 2023, scientists fully assessed all nine Planetary Boundaries, the critical Earth system processes that ensure planetary stability. This scientific framework is critical, as it allows us to; understand where we are, to prioritise our efforts and to facilitate scaled collaboration. The latest update showed that six of the nine have been breached, heightening the risk of large-scale, potentially irreversible damage to life as we know it. To safeguard a stable, resilient and liveable planet, we must respect all nine, as they collectively define the safe operating space for humanity on Earth. Achieving this requires investment in science and holistic thinking on a planetary scale, which is a great opportunity to ensure we are also protecting human health across all dimensions, such as chemical pollution, freshwater use, biodiversity protection, ocean stability and more. It also requires us to listen to and learn from the wisdom of the original stewards of the planet: Indigenous peoples. You can learn more about the Planetary Health Check here. History offers us hope. Back in the 1970s, courageous scientists such as Sherwood Rowland and Mario Molina raised an alarm that CFCs, which were in everything at the time from deodorants to refrigerators, were destroying the ozone layer. Their alarm turned out to be an early warning that was at first dismissed and then attacked, before being proven to be the alarm that would steer us away from catastrophic consequences, as a result millions of cases of skin cancer were averted, eye cataracts prevented as well as the eventual destruction of ecosystems loss that could have led to agricultural system collapse, the list goes on. Fortunately, the world mobilised across political and other divides to globally secure and implement the Montreal Protocol that saved all our lives. Science was at the centre of this collective achievement. This included the importance of the longevity of investment in science that allowed the British Antarctic Survey to irrefutably prove the damage to the ozone layer, thanks to their meticulous tracking of atmospheric data since 1957. The group of scientists and others who mobilised behind them are true collective heroes. Their courage and actions, have allowed us to continue to live on this wondrous planet. This vibrant community, active since long before the protocol’s signing in 1987, continues to thrive, driven by dedicated leaders, rotating experts and collaborative institutions such as the Ozone Secretariat. The protocol stands as a powerful example of global cooperation to protect the planet, demonstrating that scientists, citizens, independent research institutions, governments, industry and the U.N. can work together to achieve environmental breakthroughs through diplomacy, trust and shared commitment. We can do this again. This is a planetary emergency, but also a moment of opportunity. Let us not be divided by political narratives, but united by our shared responsibility and grounded in modern and Indigenous people’s science. This commentary was written on behalf of the Planetary Guardians: Hindou Oumarou Ibrahim (Chair), Paul Polman, JM Santos, former president of Colombia, (Co Vice-Chairs) Xiye Bastida, Ralph Chami, Wade Davis, Sylvia Earle, Farwiza Farhan, Christiana Figueres, Jane Goodall, Dr Naoko Ishii, Hiro Mizuno, Sunita Narain, Carlos Nobre, Dr Mamphela Ramphele, Mary Robinson, Ayisha Siddiqa, David Suzuki.

With hotter nights and more humidity, India’s urban heat crisis is tightening its chokehold

From purchasing air conditioners and coolers to consuming copious amounts of lemon soda and coconut water, Delhiites are preparing themselves for a prolonged and scorching summer. Peak temperatures are not merely crossing the 40-degree-Celsius mark; most cities across India are becoming hotter overall. Moreover, forecasters at the India Meteorological Department (IMD) have predicted above-normal daytime and night-time temperatures throughout May and June. The ambient air temperatures in cities such as Delhi, Mumbai, Kolkata and Bengaluru have seen a marked increase over the past decade. Data indicates that during the summers of 2001-2010, land surface temperatures dropped during nighttime by 6.2-13.2 degrees Celsius on average from the daytime peak. Between 2014 and 2024, night-time cooling has reduced dramatically to just 1.5-6.2 degrees Celsius on average. “This essentially means that throughout the season, residents are experiencing warmer average temperatures. Nature’s natural cycle of cooling is now being disrupted,” said a senior official at the IMD who did not wish to be named. Daily average temperatures have been steadily rising over the past decade, according to the IMD. “Along with daytime temperatures, we are now recording high night-time temperatures and humidity levels,” IMD Director General M. Mohapatra told ThePrint. “This means that cities are not cooling at the necessary rate, leading to an uncomfortable accumulation of heat throughout the season.” Most parts of northwest, central and eastern India are also expected to experience higher than normal heatwave days. Data further reveals that cities are witnessing a rise in minimum temperatures and humidity levels during the summer months, which has intensified the overall discomfort and unease among residents. “Such trends stress the need for climate-resilient interventions. These trends have become the new normal in some cities,” Mohapatra said. High night-time temperatures and humidity The narrowing gap between maximum and minimum temperatures as the season progresses has emerged as the primary reason for prolonged spells of extreme heat. Rising minimum temperatures are worsening the situation. Mahesh Palawat, Vice President (Meteorology and Climate Change) at Skymet Weather—a private weather forecasting service—explained that after a high heat day, nighttime is when the atmosphere usually cools down. High daytime temperatures, which circulate closer to the surface, rise to allow the cooler night air to settle. This is how nature cools a region. But this cooling mechanism is being blocked by factors such as dense urbanisation and dwindling green spaces. “It is simple science. When warm air isn’t allowed to escape, it remains trapped near the surface. The next day, more warm air is added to this, until eventually the seasonal temperature becomes unbearable,” Palawat said. An analysis by the Centre for Science and Environment (CSE), a Delhi-based environmental think tank, showed that the annual mean land surface air temperature over India during 2023 was 0.65 degrees Celsius above the long-term average. The report highlighted that the decadal summer-time average ambient temperature has risen by approximately 0.5 degrees Celsius in Mumbai, Bengaluru and Chennai compared to 2001-2010. Kolkata’s decadal average also increased by 0.2 degrees Celsius. The report also noted that urban centres were not cooling at night. “When night-time temperatures remain high, people get little chance to recover from daytime heat,” Dr Dileep Mavalankar, former director of the Indian Institute of Public Health in Gandhinagar, told ThePrint. When nights remain consistently warm, the risk of heat-related mortality also increases, he warned. High relative humidity levels are compounding the summer’s discomfort. The CSE report indicated that average relative humidity significantly increased over the last 10 summers—between 2014 and 2024—compared to the 2001-2010 average. In Delhi, Mumbai, Kolkata, Hyderabad and Chennai, the decadal summer-time average relative humidity rose by five to ten percent. “This increase has worsened heat stress in warm-humid and moderate climate zones,” the report stated. Experts say these factors—often overlooked by weather monitoring agencies—reveal the actual impact of heat. Anumita Roychowdhury, executive director, Research and Advocacy at the CSE, told ThePrint that with summers becoming more dangerous, it is imperative that heat be monitored holistically to save lives and reduce damage on the ground. “Assessing the changing trends in heat, relative humidity and land surface temperature alongside day and night temperatures is necessary to develop a comprehensive heat management plan for urban centres,” Roychowdhury said, adding that the IMD’s heat recordings were not the most accurate representation of heat’s impact on the ground. The IMD has started issuing advisories that include what the day ‘feels like’. “The way weather trends are moving these days, temperature readings alone are insufficient. The daytime temperature might be 40 degrees Celsius, but when combined with factors such as high humidity and urban heat islands, it feels significantly more intense,” a senior IMD scientist said. Urban heat islands Data from the IMD over 10 years showed that peri-urban areas cool down by 12.2 degrees Celsius, while the city core cools down by only 8.5 degrees Celsius. This indicates that city centres are cooling 3.7 degrees Celsius less than surrounding areas. In Delhi, a direct correlation is observed between high heat stress and the increase in built-up area, which has risen from 31.4 percent in 2003 to 38.2 percent in 2022. Granular analysis of Delhi’s temperature trends also revealed that 80 percent of the city’s monitoring stations recorded higher temperatures than the representative station at Safdarjung. This indicates that a majority of the city is enduring a much harsher season than projected by the Met department. “Factors such as green cover and open spaces play a significant role in temperature readings. Safdarjung is also an area that is not as densely populated as many other pockets in Delhi. To provide a more accurate picture, the IMD could average readings from multiple observatories. This would give a more transparent reflection of the temperatures experienced by residents,” Palawat said.

These Bengaluru Volunteers Tackle the Mountain of Waste Left Behind After IPL Matches

The roar of the crowd. The crack of the bat. The thrill of a six soaring into the night sky. The Indian Premier League (IPL) is a spectacle like no other. But once the final ball is bowled and the excitement dies down, what is left behind tells a different story. We see piles of plastic bottles, crumpled paper cups, food wrappers, and disposable plates scattered across the streets outside the stadium. While the spotlight fades, a determined group steps in to make a change. Team Saahas, an environmental NGO based in Bengaluru, together with volunteers from the Solid Waste Management Round Table (SWMRT) Bengaluru, leads a movement to tackle this mounting waste problem. As most fans head home, these volunteers stay back, gathering waste, sorting recyclables, and doing the crucial work of restoring the space to what it was before the match. But their work goes far beyond just cleaning. These volunteers are here to shake us out of our apathy. They remind us through action that our waste is our responsibility and that real change begins with conscious steps. Each IPL match draws tens of thousands of spectators, and with them comes an avalanche of waste. In our pursuit of entertainment and convenience, we often overlook the environmental degradation and overflowing landfills. Would we toss garbage so carelessly if the stadium were our living room? This question helps us answer how we can tackle this problem. What can fans do? Fans can play a huge role in reducing waste during matches. Here are a few practical, impactful choices: 1. Carry a reusable water bottle (if permitted by venue regulations). 2. Avoid purchasing heavily packaged snacks; you can opt for food with minimal wrapping. 3. Use designated waste bins, and if you see an overflow, report it to the helpdesks. 4. Encourage friends and family to do the same. What should organisers implement? Event organisers have the power to shift behaviours at scale. Here is how they can lead the way: Advertisement 1. Deploy visible “Green Teams”, which can be volunteers who guide and educate fans on proper disposal. 2. Offer incentives for clean behaviour, like returning waste, which could earn fans discounts or freebies. 3. Install waste segregation stations every 100 metres, guaranteeing convenience and visibility. 4. Work with local authorities to enforce plastic bans and monitor compliance. Why stadium waste deserves attention Stadiums in India generate a massive amount of waste. A 2018 report by the Centre for Science and Environment (CSE) estimated that sporting venues can produce three to five tonnes of waste in a single day, depending on crowd size and event duration. Most of this comprises plastic bottles, disposable cutlery, food containers, and multi-layered packaging. India already struggles with its burgeoning waste problem. The country generates over 62 million tonnes of municipal solid waste annually, as reported by the Ministry of Housing and Urban Affairs. With the increasing frequency of large-scale urban events, the pressure on waste management infrastructure is mounting rapidly. There are rules in place. The Plastic Waste Management Rules (2016) and the 2022 nationwide ban on select single-use plastic items aim to curb consumption at source. But enforcement is often patchy. A 2023 audit by the Central Pollution Control Board (CPCB) revealed that compliance at public events is inconsistent, particularly where responsibility is left to local authorities. Even when bins are available, waste often ends up mixed and unusable due to improper disposal by vendors and attendees. This is where organisations like Saahas and SWMRT step in, but without systemic change, their efforts remain more reactive than preventative. Let’s leave behind more than memories Sport is powerful. It unites, excites, and inspires. But it should not come at the cost of our environment. As cricket fans, organisers, and citizens, we must take ownership of the spaces we share. The match may end in three hours, but the waste can last for decades. So next time you are cheering for your team, remember that the most meaningful win might not be on the scoreboard. It might be in the bin you used instead of the floor. Edited by Khushi Arora and Leila Badyari; Pictures courtesy Saahas

At 681, Haryana wheat burning cases hit 4-year low

Gurgaon: Haryana recorded 681 farm res between April 1 and May 4 — its lowest in four years. The drop marks a positive shi in the state's ght against crop residue burning (CRB), a major source of seasonal air pollution and soil degradation. The practice of burning wheat stubble, especially common in April and May aer the rabi harvest, is used to quickly clear elds for the next crop. In previous years, Haryana reported 2,459 res in 2022, 775 in 2023 and 1,157 in 2024 during the same period. Indian Agricultural Research Institute (IARI), which has shared the gures, attributes the consistent yearon-year decline to growing awareness among farmers, improved enforcement of regulations and the increased adoption of sustainable stubble management practices. According to experts, the wheat season also impacts air quality. Research associate at Centre for Science and Environment (CSE) Shubhansh Tiwari said, "Haryana is witnessing low farm res as many startups are now buying the residue from the farmers. The farmers are getting equipment to manage their farms and there is awareness as well." "I feel that in the paddy season it may continue. CRB is very critical as prolonged periods of stagnant air can trap pollutants, leading to persistent haze, reduced visibility and increased respiratory issues — particularly among vulnerable communities, " Tiwari said. The practice of CRB is a major concern, as it releases harmful pollutants into the atmosphere, aecting public health and the environment. Haryana agriculture department (Jhajjar) Mohit Kumar said public awareness campaigns which have been carried out over the years are "yielding results" to educate farmers and the general public about the negative consequences of CRB and the importance of adopting eco-friendly alternatives.

How Humidity Is Breaking Your Body’s Thermostat

Mumbai was not having an unusually hot day at 33.9 degrees Celsius if we only go by the mercury. But with 69% humidity, the impact felt on the human body was as good as 46 degrees. And this wasn’t even the hottest day of the season. In comparison, the ‘felt temperature’ in Rajasthan’s Barmer with the maximum temperature of 46.8°C but 9% humidity (April 30, 5.30 p.m) was a lower 43.6°C. As India grows warmer, it is also getting more humid, particularly on the coasts and the Northeast region which historically have higher humidity as compared to the plains. It is therefore essential to also monitor and study the impact of humidity on heat outcomes and health for hundreds of millions of Indians. New research shows that the combined effect of temperature higher than 32 degrees and humidity beyond 60% is hazardous for the human body, especially among outdoor workers with sustained exposure. Many stations in Konkan, Goa, Gujarat, Tamil Nadu, Kerala, Odisha, West Bengal are surpassing this limit on the daily in summer. What’s more is that the research warns that at temperatures above 32°C, each 10% increase in relative humidity resulted in a 22% increase in physiological strain on participants. Humid heat inhibits the body’s ability to cool down through its natural mechanism of sweating. And humidity has increased across India at the rate of 0.79% per decade during the period of 1969 to 2012. “Humidity is an almost forgotten factor when it comes to Indian settings. Everybody is talking about heat,” said Vidhya Venugopal, faculty of public health at Sri Ramachandra Institute of Higher Education and Research, Chennai. “The kind of heat one experiences in Rajasthan is very different from Gujarat, Tamil Nadu. There are differences even within a state. How your body reacts to 20% humidity is different from 60% humidity.” “When you sweat so much, there is cellular dehydration and electrolyte imbalance. We must pay attention to the humidity factor in our approach to extreme heat,” said Venugopal, whose research area is extreme heat and health. High humidity levels coinciding with high temperatures are likely to create lethal weather conditions and imperil the lives of millions across large parts of the subcontinent, as IndiaSpend reported in August 2017, based on research published in the scientific journal Science Advances. Climate change will make such conditions more frequent as the 21st century comes to a close. IndiaSpend wrote to the Union Ministry of Health on what steps it is taking to issue advisories to people and various stakeholders to protect from or mitigate the impact of humid heat. We will update this story when we receive a response. Perspiration nation As has been the trend for a few years now, warmer temperatures set over India as early as February this year, obscuring the spring. The India Meteorological Department (IMD) has been issuing heatwave alerts right from March. The IMD measures heat throughout the day for hundreds of weather stations which is marked by the day’s maximum temperature. The same is done for minimum temperature at the end of every night. Each weather station has a ‘normal’, and the departure from this normal shows how much hotter or cooler it is than usual. All weather stations also record relative humidity , which is the measure of how much water vapour is contained in the air as compared to how much it can hold. This is expressed in percentage. However, when issuing information on extreme heat or record-breaking heat, only temperatures are taken into consideration. The threshold for declaration of a heatwave is also dependent on the same, but there are lower thresholds for coastal locations as compared to the plains. Due to high humidity, there might be a reason to re-draft these guidelines. In coastal areas, a heatwave is declared if the temperature crosses 37°C for two consecutive days in at least two stations. This threshold is 45°C for a station in the plains. However, if one considers a maximum temperature of 36°C, just one degree lower than the criteria, and factor in 60% humidity, the ‘felt temperature’ or ‘heat index’ as per this calculator is 48.1 degrees, higher than the ‘mark’ for a severe heatwave. In other words, the human body will experience thermal discomfort high enough to be categorised into a ‘severe heat wave’ and yet, the station will not even record a ‘heatwave’. (It must be noted that relative humidity varies as per the time of the day, location and other factors whereas maximum temperature is one value at one time of the day). Declaration of a heatwave means that various stakeholders from the Union ministries to the concerned local authorities can take measures to prepare for extreme heat outcomes. This includes taking care of those most vulnerable to heat (infants, elderly, people with chronic diseases), issuing alerts and advisories to people. In case of a red alert, there are chances of a heat stroke and extreme care is needed for the most vulnerable. Our survival depends on our bodies staying at a consistent temperature. Normally, our core temperature--from the top of the head to mid-chest, encompassing the brain, lungs and chest--is regulated at 37°C, and our skin at 35°C. Sweating helps us shed excess heat--sweat beads cool the skin, and evaporation of sweat gets rid of heat, restoring the equilibrium. This process of thermoregulation occurs efficiently only when ambient air is favourable for us. Air can hold a limited quantity of water until it saturates. In dry air without much water content, your sweat evaporates quickly, causing cooling. In humid air that has much moisture already, sweat does not evaporate as easily, leading to overheating of the body. Physical labour--such as on farms, where 48.8% of Indians work--becomes unsafe in such conditions, and can prove fatal, as IndiaSpend reported in July 2021. And this is not in the future. India lost around 259 billion hours of labour annually between 2001 and 2020 due to the impacts of humid heat, as IndiaSpend reported in January 2022 based on a study from researchers at Duke University. The loss of these productive hours cost India $624 billion or about 7% of its 2017 gross domestic product. Felt temperature is the thermal discomfort the human body feels and is a combination of maximum temperature and relative humidity. If we add solar radiation and wind speed to it, it gives us a ‘wet bulb globe temperature’. There are discussions globally on whether the WBGT might be the most accurate depiction of temperatures. Either way, meteorologists around the world are now talking about extreme heat not just in temperature numbers but in terms of ‘heat stress’. IMD has been issuing a forecast for ‘hot and humid weather conditions’ for a few years now. For example, on April 17 it forecast that such weather is likely to prevail over Gujarat that day; and in Marathwada and central Maharashtra during April 17-21. ‘Hot and humid weather’ is when maximum temperatures remain 3°C above normal along with above-normal relative humidity. However, these alerts are different from the colour-coded alerts issued by IMD, such as yellow, orange and red to denote heatwaves in summer. “Humidity is more dynamic than temperature,” explained an IMD scientist who did not wish to be named. “Humidity cannot have a national mean because it changes throughout the day. As temperature rises, the air’s capacity to hold moisture also rises. You cannot have one figure for the entire day also. “For our experimental heat index, we are using temperature and humidity figures of 2.30 p.m. but for this heat index or wet bulb globe temperature to become the norm, data is not available in India. We need more studies and data on physiological response from India. It is a multiple stakeholder process beyond IMD,” they added. The officer was referring to an experimental heat index that IMD has been issuing for the last three years wherein it measures ‘apparent temperature’. Just like the calculations for ‘felt temperature’ used earlier, this heat index measures the heat stress the body is expected to feel and is a combination of air temperature and humidity. It is derived using a formula similar to the one being used in the USA but it is not validated across India. Senior IMD scientist R.K. Jenamani said that the IMD is trying a number of new things. “In order to look at different thresholds, heat index, we also need all-cause mortality data. But we have started giving hot and humid weather alerts. Everyone is considering humidity, it is definitely a parameter. We are starting a lot of new things. In our daily forecast, we are now forecasting relative humidity also,” said Jenamani. The scientist was referring to an annexure in the daily press communication wherein based on the day’s humidity, IMD has been forecasting the next day’s humidity levels across India as a percentage range. Stranded on a heat island The phrase ‘urban heat island effect’ has become ubiquitous in Indian cities. In simple terms, it is the warming effect felt in cities as compared to their nearby rural areas because of construction material used, concretisation, greenhouse gas emissions etc. trapping more heat within those cities. A 2024 report by Delhi-based Centre for Science and Environment analysed three factors that contribute to heat stress in six megacities of India during summer--air temperature, land surface temperature and relative humidity. Its findings showed that humidity had contributed to a significant increase in these cities’ heat stress. In Chennai, one of the hottest and most humid places in India, humidity was responsible for adding on average 6.3°C heat stress to the city. That is because Chennai’s summertime has registered 0.4 degrees increase in ambient temperature as decadal average, while its relative humidity has increased by 5% between 2001-10 and 2014-23. “There is direct co-relation between increase in built up area and increase in urban heat stress,” the CSE analysis on Chennai found, adding that the city’s built up area has increased from 30% in 2003 to about 74% in 2023, while green cover fell from 34% to 20% in the same time. Kolkata also had identical numbers but less of an urban heat island effect. In Mumbai, summertime has registered a 0.6°C increase in comparison while relative humidity has increased by 7% between 2001-10 and 2014-23. High humidity was responsible for adding, on average, 5°C of heat stress to the city. Mumbai’s built up area has increased from 38% in 2003 to 52% in 2023 while its green cover has decreased from 36% to 30% in the same time period. And across India, as we said, humidity increased at the rate of 0.79% per decade during the period of 1969=2012. Global warming has a role to play here as well. A 2011 research paper stated that “there is a direct influence of global warming on precipitation. Increased heating leads to greater evaporation and thus surface drying, thereby increasing the intensity and duration of drought. However, the water holding capacity of air increases by about 7% per 1°C warming, which leads to increased water vapor in the atmosphere.”

Winter PM2.5 Trends Paint A Bleak Picture For Mega Cities

Irrespective of their diverse geographic and climatic contexts, the megacities of India – Delhi, Mumbai, Kolkata, Bengaluru, Hyderabad and Chennai - have seen worsening PM2.5 levels during the winter of 2024-25 (October 1, 2024-January 31, 2025). The overall level and the peaking points of pollution have, however, varied across cities depending on the meteorological conditions of different climatic zones. This has emerged from a new analysis of real time PM2.5 data in these cities during the winter period. The analysis, done by Centre for Science and Environment (CSE), has evaluated pollution trends in peer megacities and provides insights into long-term seasonal variations and annual shifts in particulate pollution during winter. While Delhi, located in the land-locked Indo-Gangetic Plains (IGP) with adverse meteorology, has recorded the highest level of pollution during winter, Kolkata -- also at the tip of the IGP – ranks second. The megacities outside the IGP -- Mumbai, Chennai, Hyderabad and Bengaluru -- despite having more advantageous climatic conditions and natural ventilation, have also experienced increases in average PM2.5 concentrations. Other than Delhi and Chennai, all other megacities have recorded city-wide winter averages that are comparatively lower than the average of the past three winters; but the concentrations across different locations have been high, leading to high exposures. “The peaking of pollution during winter in any climatic zone is a sign of the underlying problem of persistent air pollution in these rapidly urbanising and motorising cities. The growing impact of local sources of pollution shows up in the pollution hotspots across these cities, increasing local exposures and risks,” says Anumita Roychowdhury, executive director, research and advocacy, CSE. “These cities need stringent action to curb pollution from all sources to meet the clean air standards. But urban centres like Delhi and Kolkata that face an additional challenge of adverse meteorology which enhances the concentrations, need even more stringent action to counter these effects,” Roychowdhury adds. According to Sharanjeet Kaur, programme officer with the Urban Lab at CSE, “While Delhi’s winter air quality often dominates public discourse, rising pollution levels in other megacities remain largely overlooked. Despite some improvement in seasonal pollution trends, winter pollution continues to remain high or has been rising locally.” The methodology behind the CSE analysis This is an assessment of annual and seasonal trends in PM2.5 concentrations for the period October 1 to January 31 in the years 2021-22, 2022-23, 2023-24, and 2024-25. Data points have been cleaned and data gaps addressed based on the USEPA method. The analysis has been done on the basis of real time data available from currently working air quality monitoring stations in Delhi, Kolkata, Mumbai, Chennai, Hyderabad and Bengaluru -- 115 continuous ambient air quality monitoring stations (CAAQMS) have been covered. Delhi (40), Kolkata (seven), Mumbai (31), Hyderabad (14), Bengaluru (14) and Chennai (nine) have more than one real time station, therefore city-wide averages have been used for comparative analysis: it is defined as average of all city stations that have been functional for the given study period. During this winter, Kolkata and Hyderabad were most polluted after Delhi, while Mumbai, Chennai and Bengaluru saw the fastest worsening of localised pollution levels: Delhi, with a winter average PM2.5 level of 175 microgramme per cubic metre (µg/m³) remains the most polluted megacity by a large margin during winter, even though the winter average has shown improvement over the previous winter. In the other five megacities, the average winter PM2.5 level was 65 µg/m³ in Kolkata; 52 µg/m³ in Hyderabad; 50 µg/m³ in Mumbai; 36 µg/m³ in Chennai; and 37 µg/m³ in Bengaluru. Kaur points out that winter averages cannot be directly compared with a 24-hour average or an annual average. She says: “Indicatively, daily standards for PM2.5 are 60 µg/m³ and annual standards are 40 µg/m³. But city average is not an adequate indicator for high exposures in these cities.” Longer-term trend in winter averages in mega cities: When compared to the three-year average, Delhi remained the worst performer, with average winter pollution levels continuing to rise, even though by just 1 per cent higher than the average of the last three years. Compared to the winter of 2021-22, Mumbai, Kolkata and Hyderabad show improvement with their winter PM2.5 levels dropping by 16 per cent, 14 per cent and 16 per cent respectively.

New construction waste rules push for producers’ accountability and recycling

New construction and demolition waste rules now require producers to take responsibility for their waste, pay penalties for violations, and report activities for monitoring through a central online system. Construction and associated waste generation have been increasing sharply, but previous regulations failed to address the waste-related challenges effectively. Experts express cautious optimism about the new rules but also point towards scope for improvement. India’s environment ministry has introduced Extended Producer Responsibility (EPR), mandatory recycling targets and other provisions to promote recycling and sustainable waste management in the construction and demolition (C&D) sector. Under the newly notified Environment (Construction and Demolition) Waste Management Rules, 2025, local or development authorities are now required to include waste recycling provisions in approvals for all construction projects. The rules mandate that EPR targets in construction, reconstruction and demolition projects be regulated through a waste management plan. “Every producer shall prepare a waste management plan in respect of each project which shall assess the quantum of waste from all streams in a construction, reconstruction and demolition project and submit it to the local authority for approval,” it said. The rules define the responsibilities of waste generators (or producers), requiring them to collect and segregate waste into separate material streams, store it safely, and ensure recycling or proper handover to authorised agencies or recyclers. They must also take necessary measures to prevent air pollution, avoid littering, and minimise public nuisance during waste collection, segregation and storage. “The revised rules mark an important shift by placing more responsibility on waste generators and encouraging private sector participation,” said Sree Kumar Kumaraswamy, Program Director, Clean Air Action, WRI India. “This creates opportunities for new business models in C&D waste management and enables data-driven planning through digital tools like the online portal.” When calculating EPR targets, debris such as cement concrete, bricks, plaster, stone, rubble, and ceramics will be considered. However, reusable or resalable materials, such as iron, wood, plastic, metal, and glass, will not be counted towards EPR targets and will be managed under prevailing regulations. The new rules also mandate the utilisation of processed C&D waste in certain construction activities. As per it, projects with a built-up area of 20,000 square metres or more and road construction projects must use processed waste. Local authorities are responsible for monitoring compliance. The rules also talk about waste storage facilities. Urban Local Bodies (ULBs) must identify and set up intermediate waste storage facilities and processing sites — locally or on a cluster basis — within one year. They are also responsible for establishing collection points, ensuring waste transport to registered recyclers. Non-compliance cases must be referred to the State or Union Territory Pollution Control Boards, as per the new rules. The rules also introduce provisions for environmental compensation. Producers, recyclers, storage operators, or developers will have to pay compensation based on the harm caused to the environment or public health if they fail to follow proper waste disposal and recycling rules. The Central Pollution Control Board (CPCB) will manage the compensation collected in a separate account. These funds will be used for collecting and recycling uncollected, legacy, or orphan waste, supporting research and development, incentivising recyclers, and aiding local bodies in managing waste effectively. The rules also talk about a central steering committee that will oversee the implementation of the rules. The CPCB Chairperson will chair it and include representatives from several ministries (Environment, Housing, Roads, Rural Development, etc.), NITI Aayog, Bureau of Indian Standards, Indian Roads Congress, recycling sector, real estate sector, and other expert bodies. The rules set clear EPR targets for waste recycling in reconstruction and demolition projects — 25% for 2025-26, rising to 100% from 2028-29 onwards. Targets for the utilisation of processed waste in construction begin at 5% in 2026-27 and increase to 25% by 2030-31 and beyond. Similar targets are set for road construction projects. Kumaraswamy said, “The mandated minimum targets for using recycled C&D waste in construction and infrastructure projects are especially promising. They can help create a reliable market, which may drive down costs over time and incentivise innovation in material recycling and reuse.” The new rules also talk about centralised interface-based online monitoring and compliance assessment. Appreciating this, Kumaraswamy said that it has a “strong potential to bring transparency to the entire C&D waste lifecycle — from generation to recycling” and, if implemented well, he added, “it can significantly strengthen compliance and data-driven decision-making, fostering a more accountable and efficient system. A growing challenge and limited progress so far The construction sector contributes 8% to India’s GDP and employs the second-largest workforce after agriculture. With ongoing urbanisation and rising aspirations, the sector is expected to grow. A joint report by think tanks Council on Energy, Environment and Water (CEEW), WRI India and RMI for the G20 Secretariat in December 2024 notes that India is already adding 700-900 million square metres of floor space annually, while the national highway network expanded by over 60% between 2014 and 2023. To meet future demands, India will need to develop 15 square kilometres of land every day until 2050, in addition to redeveloping old infrastructure. This rapid expansion is expected to increase construction and demolition (C&D) waste significantly. Estimates vary as per the report. In 2018, the Building Materials and Technology Promotion Council (BMTPC) estimated annual C&D waste to be 100 million tonnes, while the Ministry of Housing and Urban Affairs (MoHUA) projected 150-500 million tonnes in 2024. The Central Pollution Control Board (CPCB) estimates that total solid waste will reach 165 million tonnes annually by 2030. Policymakers have long recognised the scale of the challenge. A 2022 report by the MoHUA noted that India’s annual material consumption rose six-fold between 1970 and 2015 — from 1.18 billion to 7 billion tonnes — and is projected to reach 14.2 billion tonnes by 2030. In response, the Government of India introduced various regulations. The Municipal Solid Wastes (Management and Handling) Rules were notified in 2000, and in March 2016, the Ministry of Environment released dedicated Construction and Demolition Waste Management Rules. However, construction activity has surged over the past two decades, and experts say the problem of C&D waste has grown substantially. According to a 2023 report by the Centre for Science and Environment (CSE), a New Delhi-based think tank, the 2016 rules were poorly implemented and had several shortcomings. These included a lack of notification of bylaws by cities, inadequate identification of waste collection points, absence of mechanisms to promote recycled products, a weak market for recycled materials and poor institutional capacity within urban local bodies. The CEEW, WRI India and RMI report observed, “…in practise, a significant quantity of C&D waste is handled informally, either through backfilling, or illegal dumping in vulnerable areas. This has health and environmental impacts such as aggravating air pollution and GHG emissions, soil contamination, impact on climate and flooding.” “There has not been much success in the implementation of these rules,” said Bharati Chaturvedi of the Chintan Environmental Research and Action group, which works in the waste sector. According to Chaturvedi, one of the reasons why this type of waste is managed poorly is that it is not a profitable activity. “It is our job to make it a profitable and useful business, and we have not done that,” she said.