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India's farm insurance proves costly for most vulnerable

After years of low rainfall devastating soya bean crops on his central Indian farm, Dileep Patidar last year planted the pulse urad as it needs less water and he counted on the government's crop insurance scheme to cover him if it did not work out. The Indian government runs the world's largest agriculture crop insurance scheme, subsidising insurance to reduce farmers' premiums But an analysis by the Indian think tank, the Centre for Science and Environment (CSE), said farmers living in climate-vulnerable districts like Mandsaur faced higher premiums, had lower levels of insurance cover and received lower payouts compared to farmers in lower-risk districts. This undermines the purpose of a scheme that could be a crucial tool in building farmers' resilience, the analysis said. Climate change is increasingly impacting India's crops, with more than 4 million hectares affected by extreme weather events in 2024, nearly double the previous year, according to India's Atlas of Disasters, maintained by CSE. Just under half - 46 per cent- of India's 1.4 billion people are employed in agriculture, a sector that supports 70 per cent of rural households and generates 16 per cent of the country's GDP, according to Indian government data. Patidar's monsoon crops were insured, but he is frustrated at still waiting for a payout while he said farmers in neighbouring villages had already been compensated. "I checked my bank passbook and saw that around 10,000 rupees ($115) was deducted for the insurance premium, but to what end?" he asked. Launched in 2016, the farm insurance scheme aims to protect farmers' incomes by aiming to insure 50 per cent of all agricultural land by 2020, but by 2021 only 30 per cent was insured, according to the latest ofcial data. CSE Programme Director Amit Khurana said India's crop insurance scheme could be a vital safety net for climate-vulnerable farmers. But, he said, "farmers must perceive a benet in adopting it which means those vulnerable have to pay less, if at all, for better support". However, this is not currently the case. CSE analysed 2023 monsoon crop insurance data for 21.5 million farmers in agricultural districts classied by the government as vulnerable to very high and high climate change risk. insurance payouts. "From farmers' perspective, the main challenge with the insurance scheme remains the lack of transparency," said Donthi Narasimha Reddy, a public policy expert in the southern state of Telangana. Farmers often talk about not receiving any pay out after losing their crops, or the amount being too little to help, Reddy said. insurance payouts. "From farmers' perspective, the main challenge with the insurance scheme remains the lack of transparency," said Donthi Narasimha Reddy, a public policy expert in the southern state of Telangana. Farmers often talk about not receiving any pay out after losing their crops, or the amount being too little to help, Reddy said.

Hyderabad now hotter, Socio-Economic Outlook 2025 reveals

Hyderabad recorded temperatures about 1°C higher than the previous decade’s average in April 2024, indicating a rising trend of heat stress linked to the Urban Heat Island (UHI) phenomenon. The Socio-Economic Outlook 2025, tabled in the Assembly on Wednesday, explained that UHI occurs when urban areas experience significantly higher temperatures than nearby rural regions. This is caused by factors such as human activities, concentrated infrastructure, reduced green cover, heat-absorbing urban materials, limited surface water, poor airflow, increased energy consumption, and pollution. Telangana’s tropical climate, marked by hot and dry conditions, makes its urban areas especially vulnerable to the UHI effect. The Urban Heat Stress Tracker-Hyderabad report, published by the Centre for Science and Environment (CSE), highlights the growing intensity of UHI effects in Hyderabad and other urban areas in Telangana. The state government has introduced strategies to tackle the environmental and socio-economic challenges posed by urbanisation and climate change. Telangana’s Clean and Green Energy Policy 2025 aims to promote renewable energy adoption, energy efficiency, and sustainable urban development. The policy focuses on creating cooler, greener, and more climate-resilient cities. According to the Outlook report, these measures are expected to address the UHI effect directly or indirectly and improve urban climate resilience.

India warming: Surface air temperature up by 0.7°C, says Jitendra Singh

The surface air temperature of India rose 0.7 degree Celsius during 1901–2018 and the sea surface temperatures in the tropical Indian Ocean went up by 1°C between 1951 and 2015, minister for earth sciences Jitendra Singh has told Parliament, sharing the changes being brought by a warming planet. The minister also told Parliament on March 19 that global warming has led to increased monsoon variability and extreme climatic conditions. Surface air temperature refers to the temperature of the air near the earth's surface, typically measured at a height of 2 meters above the ground and is the temperature reported in daily weather reports. Sea surface temperature refers to the temperature of the uppermost layer of the ocean, typically measured in the top few millimeters (mm) to meters, and is a crucial indicator of ocean health and climate change. Concerns are mounting as for the first time, 2024 breached the 1.5 degree Celsius global warming threshold across the world. The minister said global warming has led to increased monsoon variability and extreme climatic conditions. Central and northern India and the western Himalayas have experienced a rise in extreme precipitation events. Northwest and central India have experienced moderate droughts and expansion in semiarid regions, the minister said. Coastal regions are at an increased risk of cyclone related disasters, Singh said. The Himalayan region has shown elevation-dependent warming, changes in western disturbances, snowfall patterns, retreating glaciers, and a rise in short-lived precipitation extremes, etc. “Based on published scientific studies, the sea level in the Indian Ocean was observed to be rising at a rate of about 1.7 mm per year during the last century (1900–2000) and even more rapidly in the north Indian Ocean at the rate of about 3.3 mm per year since 1993-2015,” the minister said. He was responding to a question by Bharatiya Janata Party (BJP) MP Sambit Patra on the changes in the weather cycle due to climate change and the adverse effects of global warming on India. Responding to a similar question by BJP MP Parshottam Khodabhai Rupala, the minister said the Indian Ocean has been warming rapidly over the past few decades. He added that the decaying phase of El Niño is the most influential mode contributing to more than 70–80 percent of observed heatwave days in the Indian Ocean basin. The earth sciences ministry, citing National Crime Record Bureau (NCRB) add, said 730 people died due to heatwaves in 2022, while the deaths in 2021 and 2020 were 374 and 530, respectively. India recorded the earliest heatwaves and warm nights this year, according to the Centre for Science and Environment. On February 25, Goa and Maharashtra recorded India’s first heatwave of the year, a first time for winter season (January–February). February 2025 was the hottest February in 125 years by the India Meteorological Department.

Tram tale of two cities continues — Kolkata-Melbourne Tramjatra set to begin on March 28

In 1996, with the Jyoti Basu-led left front government at the helm, few environment and tram enthusiasts from Kolkata and Melbourne initiated the Kolkata-Melbourne Tramjatra festival; officially to celebrate the tram lineage of the two cities, but, covertly, to fan support for the Kolkata streetcars as the then-state government dropped broad hints to close down the tram network in the city. Three decades down the line, with the Trinamool government announcing its decision to close down the city’s oldest public transport system, the same group of enthusiasts, in a last ditch effort to save trams, are going to organise another round of Tramjatra from March 28-31 to highlight the key role of trams as an environment-friendly transport. The regional climate security, particularly that of Kolkata and the Sunderbans — a world heritage site — will also be highlighted in the context of saving trams during the Sunderban Tramjatra, shared Mahadeb Shi, the co-curator of the programme and a filmmaker. “We do not know whether there will be another Tramjatra in the future. If trams are no longer in the city, then what will be the meaning of another Tramjatra? Hence it can be seen as a last-ditch effort to push the agenda of trams’ survival in this climate impacted world,” quipped the environmentalist. “The Sunderban Tramjatra will provide a platform to talk about both the climate threat faced by the Sunderbans and Kolkata, and the future of the tram,” observed Shi. The activist raised questions about the government’s effort to tag trams as heritage transport in Kolkata, while it has come back strongly as an effective public transport mode in more than 400 cities; and hoped that the festival will add weight to such crucial questions. “The Sunderban Tramjatra continues to help grow the friendship between Australia and India, West Bengal and Victoria, Kolkata and Melbourne — with colourful trams, informative tickets celebrating biodiversity, and strengthening the human-to-human connection,” opined Roberto D’Andrea, co-curator of the festival and a former tram conductor from Melbourne. Roberto has been the main driver behind the movement since he jumped aboard a Kolkata tram in 1995, got struck by the similarities with the trams back home, and forged the tram friendship. “The injustice of climate change is confronting,” said Mick Douglas, another co-curating artist of the festival and a professor at RMIT University in Melbourne. “While listening and learning from the Sunderbans and Kolkata situation, we are hoping to provoke global citizens to bear witness to the challenges here, and pressure societies to act justly and promptly with informed awareness. Art can change hearts and minds where credible science has been unable to,” said Douglas. A festival tram, highlighting the spirit of the Sunderbans, will run between Shyambazar and Gariahat via Esplanade from March 28 to 30, where the rides will be free and specially prepared tickets will be shared as souvenirs, informed the organisers. D’Andrea and others will engage in discussions with the passengers aboard about the issues under the scanner. In addition, there will be on-ground events like community workshops, cultural programmes and discussions amongst citizens to be held adjacent to the Esplanade Tram Terminus — which is being turned into a festival hub. Artists from the Sunderbans will be brought in to perform cultural and musical programmes. The four-day festival will conclude with a dialogue among experts and eminent citizens, focussing on the impending climate crisis in the Sunderbans and Kolkata, as well as the possible role of trams in the process, scheduled to be held on March 31, from 4.30pm to 9pm at ICCR Rabindranath Tagore Centre, Satyajit Ray Auditorium. “We are expecting a string of experts and citizens to participate in the programme, and plan to come up with a Kolkata declaration on the agenda if possible,” pointed out Shi. According to the environmentalist, the likes of environment researcher Anumita Roychowdhury from Delhi-based environment thinktank CSE; Bhargav Maitra, a transport expert and professor from IIT Kharagpur; former MP and bureaucrat Jawhar Sircar; eminent doctor and orator Kunal Sarkar; Sunderbans expert Tuhin Ghosh from Jadavpur University; environment activist Banani Kakkar, among others, have confirmed their participation. Sanjay Vashist, director of Climate Action Network South Asia, is also likely to join the panel discussion. The Sunderban Tramjatra project is supported by the Australian government through a cultural grant administered by the Centre for Australia India Relations, and RMIT University.

Hyderabad recorded its lowest winter

Hyderabad: If residents in many areas breathed easier in the recent winter in the city, there was a reason. Hyderabad recorded its lowest winter average of the highly dangerous Particulate Matter 2.5 (PM2.5) in four years, according to an analysis by the Centre for Science and Environment (CSE), New Delhi. The study, which covered the period from October 1, 2024, to January 31, 2025, also showed but pollution spikes in several industrial areas that overshadowed the improvement.

‘Hyderabad faced third worst winter pollution in country’

Hyderabad has been the third most polluted mega city among the country’s six during the winter months of 2024-25. It stands behind Delhi and Kolkata, despite being in an advantageous position - climate and ventilation wise, reveals a study carried out by the Centre for Science and Environment, Delhi. While the winter average PM2.5 (particulate matter equal to/thinner than 2.5 microns) level stood at 175 micrograms per cubic metre (µg/m³) for Delhi, the same for Kolkata was 65 µg/m³, and Hyderabad, 52 µg/m³. Chennai recorded the lowest average at 36 µg/m³, while Bengaluru, for all its traffic issues, had the next lowest at 37 µg/m³. The study obtained real time data from 115 continuous ambient air quality monitoring stations spread across the six cities - Delhi, Kolkata, Mumbai, Chennai, Bengaluru and Hyderabad - of which 14 were from the city. The study period was from October 1, 2024 to January 31, 2025. The Industrial Development Area of Pashamylaram was the most polluted location among all in the three south Indian mega cities, with a seasonal average of 62 µg/m³. It is followed by RVCE, Bengaluru, at 56 µg/m³, and Alandur in Chennai at 47 µg/m³ - both of which are the most polluted locations in the respective cities. On the brighter side, Hyderabad is one among the four mega cities other than Delhi and Chennai, which have recorded winter averages comparatively lower than the average of the past three winters. Hyderabad has also recorded the highest improvement in average peak levels, with a 51% drop in PM2.5 levels, down to 89 µg/m³ from 183 µg/m³ last year. These figures, however, do not indicate any amelioration in the conditions, as there are considerable variations within the city, marked by numerous locations with higher than average pollution levels, says the study by executive director, Research and Advocacy, Anumita Roychowdhury and programme officer with the Urban Lab at CSE, Sharanjeet Kaur While the city has recorded the lowest winter pollution in four years, in most locations, the PM2.5 levels were two to 39% higher than the annual averages, which showed strong seasonal build-up. Sanathnagar recorded the highest daily pollution peak at 182 µg/m³, while the monitoring stations at IIT-Hyderabad, Somajiguda and ICRISAT recorded the maximum spikes in PM2.5 levels. The stations installed at Nacharam TGIIC, Kokapet, and Sanathnagar recorded significant improvements in air quality compared to last year, the study said. One major red flag is the highest nitrogen dioxide concentration recorded at the Nehru Zoological Park in January this year, which had risen 2.9 times since October, 2024. Nitrogen dioxide pollution is resultant of fossil fuel combustion - indicative of vehicular pollution in the case of Zoo Park - and directly impacts respiratory health. Pashamylaram too recorded a 1.4 fold increase over the same period, the study noted.

Hyderabad Winter Pollution Levels Surpass Chennai and Bengaluru

Hyderabad air quality emerged as a significant concern, ranking as the third most polluted among six major Indian cities. This assessment stems from a comprehensive study by the Centre for Science and Environment (CSE), which analysed real-time data from 115 continuous ambient air quality monitoring stations across Delhi, Kolkata, Mumbai, Chennai, Bengaluru, and Hyderabad between October 1, 2024, and January 31, 2025. The findings revealed that Delhi recorded the highest average levels of fine particulate matter (PM2.5) at 175 micrograms per cubic metre, followed by Kolkata at 65 micrograms per cubic metre. Hyderabad’s average stood at 52 micrograms per cubic metre, surpassing Chennai’s 36 micrograms per cubic metre and Bengaluru’s 37 micrograms per cubic metre. Notably, the Industrial Development Area (IDA) of Pashamylaram emerged as the most polluted location within Hyderabad, with a seasonal average of 62 micrograms per cubic metre.Despite these concerning figures, there is a silver lining. Hyderabad, along with Delhi and Chennai, recorded winter averages lower than the average of the past three winters. The city also achieved the most significant improvement in average peak levels, with a 51% reduction in PM2.5 concentrations, decreasing from 183 micrograms per cubic metre in the previous year to 89 micrograms per cubic metre. However, these improvements do not present a complete picture. The study highlighted considerable variations within Hyderabad, with numerous locations experiencing pollution levels higher than the city’s average. This disparity underscores the need for targeted interventions and policies to address the specific challenges faced by different localities. The persistence of elevated pollution levels in certain areas calls for a comprehensive approach to urban planning and environmental management. Strategies such as promoting sustainable transportation, regulating industrial emissions, and enhancing green spaces are essential to improving air quality. Additionally, public awareness campaigns can play a crucial role in educating citizens about the sources and impacts of air pollution, fostering community involvement in mitigation efforts. In conclusion, while Hyderabad has made strides in improving air quality, significant challenges remain. Addressing these issues requires a collaborative effort from government authorities, industries, and residents to ensure a healthier and more sustainable urban environment.

Chemical Pollution: No place is safe in today’s world

In 2019, chemicals in the environment reportedly accounted for two million deaths worldwide. New chemicals are often released into the market before we have fully understood their impacts. As a result, there are gaps in our understanding of the scale and threat of the risks posed by them in our environment In 2019, chemicals in the environment reportedly accounted for two million deaths and 53 million disability-adjusted life years worldwide, says the State of India’s Environment 2025 report, quoting WHO data. The report published annually by Centre for Science and Environment (CSE) and Down To Earth magazine released at this year’s Anil Agarwal Dialogue. India’s G20 Sherpa Amitabh Kant, former deputy chairperson of the Planning Commission Montek Singh Ahluwalia, management and financial guru Raj Liberhan, and CSE director general Sunita Narain released the report Over 80 journalists and more than 20 subject experts from across India come together to discuss and understand the environmental issues and concerns that India faces Nimli (near Alwar), Rajasthan, February 27, 2025: “In the Anthropocene age, human-made chemicals are not only “forever”, but have also become “everywhere” pollutants. From high in the atmosphere to deep inside oceans, from soils and trees to uninhabited regions – they are everywhere”, according to the State of India’s Environment 2025. The Anil Agarwal Dialogue 2025was an annual conclave of journalists from India who write on environment and development issues. Over 80 journalists from across the country participated in this one-of-its-kind platform, organised every year by CSE at its facility, the Anil Agarwal Environment Training Institute, located in Nimli, Rajasthan. CSE director general Sunita Narain released the report along with India’s G20 Sherpa Amitabh Kant; former deputy chairperson of the Planning Commission Montek Singh Ahluwalia; and management and financial guru Raj Liberhan. Over three days, the media conclave touched upon a wide range of issues – from human-animal conflicts in India and the phenomena of urban heat islands and warm nights to India’s targets on renewable energy and the return of zoonotic diseases and outbreaks.

Delhi India's Most Polluted Megacity By Wide Margin: Report

Delhi remained India's most polluted megacity by a wide margin during the 2024-25 winter, with an average PM2.5 concentration of 175 micrograms per cubic metre, according to an analysis released on Tuesday. However, the Centre for Science and Environment analysis found that PM2.5 pollution in the national capital declined in the 2024-25 winter (October 1 to January 31) compared to the 2023-24 winter (189 micrograms per cubic metre). Kolkata was the second-most polluted megacity during the 2024-25 winter, with an average PM2.5 concentration of 65 micrograms per cubic metre. The analysis showed that PM2.5 levels declined in Bengaluru, Mumbai and Kolkata compared to the previous winter but remained the same in Chennai and Hyderabad. The average PM2.5 levels during the 2024-25 winter were 52 micrograms per cubic metre in Hyderabad, 50 in Mumbai, 37 in Bengaluru and 36 in Chennai.

CSE releases 2024-25 winter air pollution analysis for six megacities of India

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.

All six Indian megacities choked with dangerous PM 2.5 levels last winter, Delhi worst, shows CSE study

Last winter, all six megacities of the country recorded high average concentrations of fine particulate matter (PM 2.5), with Delhi continuing to be the most polluted, followed by Kolkata, according to a new analysis by the Delhi-based non-profit Centre for Science and Environment. The CSE’s Urban Labs assessed annual and seasonal trends in PM 2.5 concentrations for the October 1 to January 31 period between 2021-22 and 2024-25 using real-time data available from air quality monitoring stations across the six metro cities. In Delhi, the data showed, the average PM 2.5 concentration in the winter of 2024-25 was 175 µg/m³. Kolkata, Hyderabad and Mumbai were next: 65 ug/mn3; 52 ug/m3 and 50 ug/m3, respectively. Chennai saw 36 ug/m3 and Bengaluru 37 ug/m3. According to the CSE data, Delhi’s average PM 2.5 concentration was 1% higher than the average of the previous three winters, but 7% lower than the previous winter (188 ug/m3). However, the daily peak surged significantly. The Capital’s daily PM 2.5 level — 602 ug/m3, on November 18 last year — was the highest in the past four winters. In the winter of 2021-22, the daily peak was 505 ug/m3, but fell in the next two years to 400 and 364, respectively. “Even after five years of the National Clean Air Programme (NCAP), the megacities — despite investing substantial shares of the grant from the XVth Finance Commission for clean air action — are still struggling to meet clean air standards throughout the year…” said Anumita Roychowdhury, executive director, research and advocacy, CSE.

National capital’s air dirtiest among megacities during winter: Report

The megacities of India have witnessed rising pollution levels during 2024-25 winter, according to a new report. In an analysis by the Centre for Science and Environment (CSE), it is revealed that PM 2.5, a major pollutant, has peaked in Delhi, Mumbai, Kolkata, Bengaluru, Hyderabad and Chennai from October 1, 2024, and January 31, 2025. “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. Mumbai, Chennai, Hyderabad and Bengaluru, despite having more advantageous climatic conditions and natural ventilation, have also experienced increases in average PM2.5 concentrations,” the report said. Delhi’s average PM 2.5 concentration during winter increased by 1 per cent as compared to the average of previous three winters, reaching 174 micrograms per cubic metre, with peak pollution levels surging on November 18, 2024, to 602 micrograms per cubic metre. “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. National capital’s air dirtiest among megacities during winter: Report The megacities of India have witnessed rising pollution levels during 2024-25 winter, according to a new report. In an analysis by the Centre for Science and Environment (CSE), it is revealed that PM 2.5, a major pollutant, has peaked in... article_Author Tribune News Service New Delhi, Updated At : 04:45 AM Mar 19, 2025 IST fb twitter whatsapp Follow us Follow us Connect with us Connect with us featured-imgfeatured-img File photo Advertisement The megacities of India have witnessed rising pollution levels during 2024-25 winter, according to a new report. In an analysis by the Centre for Science and Environment (CSE), it is revealed that PM 2.5, a major pollutant, has peaked in Delhi, Mumbai, Kolkata, Bengaluru, Hyderabad and Chennai from October 1, 2024, and January 31, 2025. “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. Mumbai, Chennai, Hyderabad and Bengaluru, despite having more advantageous climatic conditions and natural ventilation, have also experienced increases in average PM2.5 concentrations,” the report said. Advertisement Delhi’s average PM 2.5 concentration during winter increased by 1 per cent as compared to the average of previous three winters, reaching 174 micrograms per cubic metre, with peak pollution levels surging on November 18, 2024, to 602 micrograms per cubic metre. “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. Read More Flowers Delhi India's healthcare in crisis due to dependence on private sector: RJD MP Manoj Jha' View More right-arrow Advertisement 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 PM 2.5 level of 175 micrograms 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. Kolkata was the second-most polluted megacity during the 2024-25 winter, with an average PM 2.5 concentration of 65 micrograms per cubic metre. In the other five megacities, the average winter PM 2.5 level was 52 micrograms per cubic metre in Hyderabad, 50 micrograms per cubic metre in Mumbai; 36 micrograms per cubic metre in Chennai; and 37 micrograms per cubic metre in Bengaluru. In terms of cleaner air, Mumbai had only 19 days of ‘good’ AQI, followed by Kolkata with just 11 - the lowest among megacities (excluding Delhi). In contrast, Hyderabad (21 days), Bengaluru (44 days) and Chennai (55 days) recorded higher numbers of ‘good’ AQI days.

Kol winter PM2.5 count better than Del’s, best since 2020-’21

Kolkata: Kolkata's air quality improved this winter with the average PM2.5 concentration dropping to 65 micrograms per cubic metre between Oct 2024 and Jan 2025 against 77 micrograms per cubic metre and 85 micrograms per cubic metre in the past two winters, but it still remained the second-most polluted mega city in the country after New Delhi. A new analysis by Centre for Science and Environment (CSE) found a rise in winter air pollution in all Indian mega cities — Delhi, Mumbai, Kolkata, Bengaluru, Hyderabad and Chennai — with the intensity of pollution varying due to differing meteorological conditions. Delhi, positioned in the landlocked Indo-Gangetic Plains, recorded the highest winter pollution levels, followed by Kolkata, at the tail end of the plains. The other cities benefited from more favourable climatic conditions but still experienced a rise in PM2.5 concentrations because of higher emissions, stagnant atmospheric conditions and reduced pollutant dispersion during winter. Kolkata's average PM 2.5 concentration of 65 micrograms per cubic metre was the lowest in four years, but localised pollution peaks were a cause for concern. This winter's peak — 135 micrograms per cubic metre on Nov 2 — was the same as that of the previous winter, but lower than the peaks of the previous two seasons. Among the seven monitoring stations, Ballygunge recorded the highest daily peak at 195 micrograms per cubic metre on Nov 2, indicating persistent localised pollution hotspots. Ballygunge also had the highest number of bad air days, recording 54 instances of ‘poor' and ‘very poor' AQI. Among the other station, Fort William had 29 ‘poor' and ‘very poor' days, Bidhannagar 24, Victoria 17, Rabindra Bharati University 15 and Jadavpur 13. Monitoring station data showed that PM2.5 concentrations during winter exceeded the annual average across all key locations in the city. Ballygunge recorded the highest winter average at 80 micrograms per cubic metre, a sharp increase from its annual average of 51 micrograms per cubic metre. Fort William and Bidhannagar also showed similar spikes, with winter averages of 71 micrograms per cubic metre and 67 micrograms per cubic metre respectively, compared to their annual levels of 49 micrograms per cubic metre and 46 micrograms per cubic metre. Even Rabindra Sarobar, which had the lowest annual average at 39 micrograms per cubic metre, saw its winter levels rise to 54 micrograms per cubic metre. CSE executive director (research & advocacy) Anumita Roychowdhury said the peaking of pollution during winter in any climatic zone signals the underlying issue of persistent air pollution in rapidly urbanising and motorising cities. "The growing impact of local pollution sources intensifies pollution hotspots across urban centres, increasing exposure risks," she said, adding that stricter measures were necessary to address pollution from all sources, especially in cities like Delhi and Kolkata, which face adverse meteorological conditions that increase pollution. "While Delhi's winter air quality often dominates public discourse, rising pollution levels in other megacities remain largely overlooked," said CSE Urban Lab programme officer Sharanjeet Kaur. "Despite some improvement in seasonal trends, winter pollution continues to be high, or is rising locally." Air quality trends indicate that pollution levels in Kolkata begin to rise sharply mid-Nov and persist until the end of Jan.

Pollution worsening in Indian metros

The national capital remained India’s most polluted megacity by a wide margin during the 2024-25 winter with an average PM2.5 concentration of 175 micrograms per cubic metre (µg/m³). However, a Centre for Science and Environment (CSE) analysis found that PM2.5 pollution in the national Capital declined in the 2024-25 winter (October 1 to January 31) compared to the 2023-24 winter (189 µg/m³). Kolkata was the second-most polluted megacity during the 2024-25 winter with an average PM2.5 concentration of 65 µg/m³. Irrespective of their diverse geographic and climatic contexts, 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. The analysis showed that PM2.5 levels declined in Bengaluru, Mumbai and Kolkata compared to the previous winter but remained the same in Chennai and Hyderabad. The average PM2.5 levels during the 2024-25 winter were 52 µg/m³ in Hyderabad, 50 in Mumbai, 37 in Bengaluru and 36 in Chennai. According to an analysis, Delhi with a winter average PM2.5 level of 175 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. Delhi’s average PM2.5 concentration during winter increased by 1 per cent compared to the average of previous three winters reaching 174 µg/m³, with peak pollution levels surging on November 18, 2024, to 602 µg/m³. 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. 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. “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,” the analysis said. Delhi recorded its highest daily PM2.5 level in four years, with pollution spiking to 602 µg/m³ on November 18, 2024 -- the steepest 24-hour average since 2021. This marks a 65 per cent increase from last winter’s peak and is 42 per cent higher than the city’s three-year average, highlighting a worsening pollution trend in the capital. CRRI Mathura Road saw a 20 per cent increase in winter pollution concentration, while Ashok Vihar, Vivek Vihar and Gwal Pahari recorded 11-13 per cent rises in PM2.5 levels. Anand Vihar remained the most polluted location in Delhi, recording a winter PM2.5 average of 227 µg/m³. In the NCR region, Loni in Ghaziabad emerged as the worst affected area, with a PM2.5 average of 153 µg/m³, followed by Gwal Pahari in Gurugram at 149 µg/m³. NO ? concentrations spiked sharply, especially in November-December, with Anand Vihar recording a 71 per cent increase from October to December. ITO registered the highest NO ? levels at 167 µg/m³ in December. 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. Delhi has recorded a 7 per cent reduction in pollution levels compared to the pervious winter, but 5 per cent higher than in 2021-22. Meanwhile, Bengaluru and Chennai have recorded an increase in PM2.5 levels compared to 2021-22, reflecting a worsening trend in air quality. Kolkata and Chennai showed little improvement, with Kolkata’s maximum peak level of PM2.5 stagnating at 135 µg/m³, while Chennai saw a slight reduction from 147 µg/m³ last winter to 119 µg/m³ this year. According to the analysis, in contrast, Hyderabad, Mumbai and Bengaluru recorded reductions in peak/maximum winter pollution levels. Hyderabad showed the most improvement in peak levels, with a 51 per cent drop in PM2.5 levels, down to 89 µg/m³ from 183 µg/m³ last year. Bengaluru followed with a 42 per cent decline, reducing peak levels to 67 µg/m³, while Chennai saw a 19 per cent improvement and Mumbai recorded a 12 per cent drop in its peak level, lowering its PM2.5 from 92 µg/m³ to 81 µg/m³. This winter’s peak daily pollution levels in Kolkata, Chennai and Hyderabad were lower than their previous winter peaks, but still fell under the “poor” AQI category. Kolkata’s winter peak stood at 135 µg/m³ registered on November 2, 2024; for Chennai, it stood at 119 µg/m³ registered on October 31, 2024; and for Hyderabad it stood at 89 µg/m³ registered on November 25, 2024. Air pollution trends differ across India’s megacities, with Delhi and Hyderabad experiencing their worst air quality in November, while other cities saw peak pollution in December and January. January emerged as the most polluted month for Kolkata, Bengaluru and Chennai, with air quality deteriorating further compared to previous months. Mumbai, on the other hand, recorded its worst pollution levels in December. The analysis further stated that Mumbai recorded its lowest winter PM2.5 average (49 µg/m³) in four years, a 24 per cent decline compared to previous winters. With a winter PM2.5 average of 80 µg/m³, Deonar was the most polluted, followed by Shivaji Nagar (76 µg/m³), Malad West (75 µg/m³), Sewri (71 µg/m³) and Borivali and Kandivali (69 µg/m³ each). “Kolkata recorded a seasonal PM2.5 average of 65 µg/m³ -- a 19 per cent decline compared to the previous three winters. Hyderabad’s seasonal PM2.5 average dropped to 52 µg/m³, marking a 5 per cent decline compared to previous winters. Bengaluru recorded a seasonal PM2.5 average of 37 µg/m³, marking a 7 per cent decline compared to the previous three winters. Chennai’s seasonal PM2.5 average stood at 36 µg/m³, showing 1.2 per cent increase compared to the previous three winters,” according to the analysis.