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Government-PCB push for smokeless 'chullahs'

The state environment department and the pollution control board plan to push a transition to smokeless chullahs in households to cut carbon emission, state environment minister Gulam Rabbani said at a programme on Monday. Smokeless chullahs run on fossil fuels like coal and kerosene but the emission is estimated to be 60 to 70 per cent less compared to conventional cooking modes. The chairman of the state pollution control board, Kalyan Rudra, said they would soon initiate a pilot study in several urban and rural areas with The Energy Research Institute (TERI) to assess in detail the impact of mass-scale use of smokeless chullahs on the overall emission status in those regions and would finalise the state’s strategy based on the findings. “We plan to give smokeless chullahs to all fossil fuel users in these areas and then see the impact,” said the official. “Domestic emission is a major cause of climate change in our state and we plan to aggressively pursue the transition to smokeless chullahs, which curb emissions to a large extent,” said minister Rabbani. Rabbani also spoke of achieving a “net zero status” on emission in Bengal. “Net zero” refers to the balance between the volume of greenhouse gases produced and the volume that is removed from the atmosphere. Greenhouse gases like carbon dioxide, methane and others warm up the atmosphere and trigger a range of climatic impacts, from severe heat waves to high-intensity cyclones. Environment department officials pointed out that the transition would require around ₹4,000 crore and they were exploring World Bank, global climate funds and corporate sources for funds. “According to our estimate, nearly 1.1 crore families in the state use fossil fuels, such as various types of coals and solid products derived from coal, for cooking. We will target these families (in the push for smokeless chullahs),” Rudra said, adding they had already arranged for smokeless chullahs for nearly 4,000 families. “Our initial study shows that nearly 60 to 70 per cent of the emission can be curtailed with smokeless chullahs.” In the Glasgow climate summit in 2021, India had announced that it would strive to achieve the “net zero” status by 2070. “Introducing mass-scale smokeless chullahs is a step in the right direction but we need to supplement it with gas ovens and then finally electric heaters,” said Anumita Roy Choudhury of the Centre for Science and Environment (CSE), which is playing a role in preparing a climate action plan for Bengal.

Air quality in summer stayed poor but govt yet to spell action plan

The Capital is yet to see a summer action plan against air pollution despite the city recording an air quality index in the “poor” or “very poor” category in 37 out of the last 102 days (nearly 36%) since March 1. The summer action plan was introduced by the Delhi government in each of the last two summers to tackle dust and other summer-related pollutants. Government officials said that there was a delay in announcing a new plan this year due to the recently held Lok Sabha elections and for which the model code of conduct was in place. However, this year’s plan is likely to be out soon, they added. HT looked at the Central Pollution Control Board’s (CPCB’s) air quality index (AQI) data from March 1 onwards, when temperature is high and dust becomes a significant pollutant, leading to a rise in the PM 10 concentration. Gases such as ozone, carbon monoxide and nitric oxide also become prominent pollutants at this time of the year, when meteorological conditions are otherwise favourable. Data showed that each of the four months of March, April, May and June (till June 10) have been worse than the corresponding period last year, recording a higher average AQI and more “poor” or “very poor” days during this period. The average AQI in March this year was 176 while it was 170 last March. It was 182 this April as against 180 last April. May recorded a significantly worse average AQI of 223, as compared to 171 last summer. In the first 10 days of June, the average AQI so far is 203, up from last year’s corresponding period, when it was 150. CPCB classifies an AQI between 0-50 as “good”, between 51 and 100 as “satisfactory”, between 101 and 200 as “moderate”, between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”. Data also showed that Delhi recorded “poor” or “very poor” air quality on 37 days this summer – five in March, seven in April, 20 in May and five so far this month. In comparison, the figure was 30 for the corresponding period, with the highest, 12, in April. The Delhi government told HT that Delhi’s environment minister Gopal Rai will hold a meeting with the forest and environment department on Tuesday to finalise a plan for this summer. “The delay was mostly on account of the recent elections. The model code of conduct was also in place. Now that it is lifted, the plan will be out soon,” a government official said on condition of anonymity. Last year, Rai had started holding meetings with the departments of the Delhi government from April onwards and a 14-point summer action plan was launched by Delhi chief minister Arvind Kejriwal on May 1. The plan had short-term, medium-term and long-term measures to tackle sources such as dust pollution, industrial pollution, open burning and solid waste management, with the government deploying 84 mechanised road sweepers, 609 water sprinklers, 185 anti-smog guns, along with patrolling teams – both during the day and night to keep a tab on pollution sources in Delhi. In 2022, the plan was introduced on April 12 and the 14-point plan focused on road dust and burning of waste, both in the open and at landfill sites. Prior to that, the government had only been releasing action plans for air pollution in the winter. “We discussed the problem of air pollution with the departments concerned and came to a conclusion that in order for the winter action plan to be effective, a constructive summer action plan is also required,” Rai had said. Anumita Roychowdhury, executive director, research and advocacy at the Centre for Science and Environment, said seasonal-specific action plans target the sources that are unique to that season, which in this case is mainly dust. “This helps to take emergency action to some extent. We need such plans in place, as this has been a difficult summer, particularly a dry one, in which dust and ozone can be prominent pollutants. At the same time, it is important that the government focuses on round-the-year action,” she said.

Agenda in the time of climate change

As you read this, India will have a new-old government for the next five years. In my view, the agenda for the next government is the old one, but with a fundamental difference. This must be India’s agenda for development in and for the age of climate change. There is also the fact that the list of priority action areas remains the same. We have unfinished business when it comes to virtually everything — from energy to water and sanitation to food and nutrition to, of course, health and education. We know that the last government had schemes in place and budgets allocated for all these issues. But we also know that ensuring the welfare and well-being of people is a work in progress. During this election, as journalists fanned out to listen to the opinions of voters, we heard that unemployment was a major concern; lack of clean drinking water and sanitation topped the agenda; the energy crisis was still wicked as the price of the liquefied petroleum gas cylinder was unaffordable and electricity unreliable. Farmers are still distressed. So, a lot of work still needs to be done, and in areas that the last government said it had checked off on its to-do list. This should not come as a surprise. India is a vast country, with a massive deficit in governance. The last mile for any government scheme is about making sure that it reaches people — not once but every time. This is now combined with the impact of climate change where every day some or the other part of the country is being battered by at least one extreme weather event. This has huge implications for development programmes — unseasonal rain and extreme weather lead to more drought, flood, and loss of livelihood, putting an additional strain on the resources of the government. This is why the future agenda must recognise that the imperative of development is about scale, speed, and imagination, which takes into account the need to do development differently. We need a new imagination in the design of development schemes. For long, governments have been caught between a welfare approach — which is often dismissed as a handout — and a capitalistic minimum-government approach. In my view, this age of climate risk needs a new narrative. The government needs to rework and re-engineer development so that it is inclusive, affordable and, so, sustainable. This means re-imagining the way we work in almost every sphere — from the supply of clean water, so that it is not resource- or capital-intensive, to the access to energy so that it is clean but, most importantly, affordable. This will require changes in design and then in delivery. We need a new development paradigm that can work for the planet, but for this, it needs to work for every last person. What is important to note is that in most cases, the government has schemes and budgets. What we need is to learn from what is working and what is not. We need transformational action; and for this we need to ensure implementation -- and as I said with drive and obsession. But for all this to be possible we need two next-generation reforms. And this then is the make-or-break agenda for the government in my view. One, we need to strengthen the ground-level institutions, where local people take part. We need participatory democracy to make development programmes work. It is now over 30 years since the country passed the 73rd and 74th amendments to the Constitution to empower people’s institutions — the Panchayati Raj in rural areas and the municipal system in urban India. We have also experimented with deepening democracy by strengthening Gram Sabhas or village assemblies. But all this is unfinished work. We have much more to do to give control over natural resources to village and city governments. We need them to manage funds and schemes; to create green jobs; and to invest in natural resources for livelihoods. We need to celebrate the noise of democracy. We also need to strengthen the institutions of governance for a new India. Over the past few years, most conventional institutions have been deliberately, or by sheer neglect, allowed to decay. But the fact is governance and regulation need institutions that can apply deterrence with accountability and have the ability to navigate inconvenient and tough decisions. Two, even more tomorrow than today, governance will need increased feedback and accountability. This needs tolerance for voices that differ. It is important to understand that alternative information is not dissent or targeted criticism. The more we learn about what is working and what is not, the more governance improves. Currently, most differing voices have been silenced. It is like an echo chamber where only cheerleaders thrive. In my view, this only makes a government poorer — they hear nothing and learn little. Rebuilding trust is the key — not just for schemes to succeed but also for societies to thrive. This has to be the agenda. This is the time for change; for society to build green because it is inclusive; to build growth, because it is sustainable. The writer is at the Centre for Science and Environment sunita@cseindia.org, X: @sunitanar

Action agenda for new government

New Delhi: A new government is preparing to take charge in the country, and we believe it is a time to recommit to an agenda of development -- one which is inclusive and affordable and hence, sustainable for all. And June 5 is the appropriate date to make that commitment once again, according to Sunita Narain, director general, Centre for Science and Environment (CSE) and editor of Down To Earth, in a new podcast and video released by CSE to mark the World Environment Day. “In my view, the agenda for the next government is the old one, but with a fundamental difference. This must be India’s agenda of development in and for the age of climate change. In this age of climate change, the list of priority action areas remains the same. We have unfinished business when it comes to virtually everything: from energy to sanitation, and from health to education. We know that the last government had schemes in place and budgets allocated for all these issues. But we also know that ensuring the welfare and well-being of people is a work in progress. A lot of work still needs to be done, and in areas that the last government said it had checked off in its to-do list.

Kolkata reeling under heat even at night – But why? Know the reason

The monsoon is still a few days away, but Kolkata residents are already experiencing a pressure cooker-like daytime climate with a high temperature of 37°C and a relative humidity of about 90%. The heat island effect keeps the city from cooling down sufficiently, even after sunset, so there is no reprieve from the oppressive heat at night. On Friday, the actual feel temperature in Kolkata was a blistering 50°C. According to a study conducted by the environmental NGO Centre for Science & Environment (CSE), Kolkata is not becoming as cold at night as it did in the first ten years of the century. “Increase in built-up area, loss of greenery, and reduction in water bodies have resulted in Kolkata losing its night-time cooling power,” said Avikal Sombanshi of CSE’s Urban Lab. According to experts, the impact of urban heat islands is greater at night than it is during the day. The core Kolkata areas, which stretch from Dum Dum in the north to Garia in the south, have the lowest nighttime land surface temperature (LST) decline, according to a CSE study. The average low temperature (LST) in the city core decreased from 32.5°C during the day to 25.8°C at night in 2018–2023, in the outer city from 31.6°C to 25°C, and in the periurban areas beyond Singur and Ashok Nagar in the north and Diamond Harbour and Kharagpur in the south from 30.7°C to 24.6°C.

Kolkata reeling under heat even at night – But why? Know the reason

The monsoon is still a few days away, but Kolkata residents are already experiencing a pressure cooker-like daytime climate with a high temperature of 37°C and a relative humidity of about 90%. The heat island effect keeps the city from cooling down sufficiently, even after sunset, so there is no reprieve from the oppressive heat at night. On Friday, the actual feel temperature in Kolkata was a blistering 50°C. According to a study conducted by the environmental NGO Centre for Science & Environment (CSE), Kolkata is not becoming as cold at night as it did in the first ten years of the century. “Increase in built-up area, loss of greenery, and reduction in water bodies have resulted in Kolkata losing its night-time cooling power,” said Avikal Sombanshi of CSE’s Urban Lab. According to experts, the impact of urban heat islands is greater at night than it is during the day. The core Kolkata areas, which stretch from Dum Dum in the north to Garia in the south, have the lowest nighttime land surface temperature (LST) decline, according to a CSE study. The average low temperature (LST) in the city core decreased from 32.5°C during the day to 25.8°C at night in 2018–2023, in the outer city from 31.6°C to 25°C, and in the periurban areas beyond Singur and Ashok Nagar in the north and Diamond Harbour and Kharagpur in the south from 30.7°C to 24.6°C.

Heat Stress Exposes Dangerous Trends in India’s Biggest Cities

Amid ongoing scorching summer, six mega cities across India are facing an unprecedented heat wave that is worsening the urban heat island effect. This has been revealed by a latest study done by New Delhi-based Centre for Science and Environment (CSE). The CSE study highlighted that heat stress is not just about rising temperatures. It is a deadly combination of air temperature, land surface temperature and relative humidity that leads to acute thermal discomfort and heat stress in cities. The CSE has tracked heat in six megacities—Bengaluru, Chennai, Delhi, Hyderabad, Kolkata and Mumbai. The time frame of the study is the summer of January 2001 till April 2024. “An unprecedented heat wave has been enveloping Indian cities, worsening the urban heat island effect, this summer. There are far deeper and longer term evidences on the nature of this changing trend that is impacting India’s biggest cities” the study said. Anumita Roychowdhury, executive director, research and advocacy at CSE, said in a statement that: “Assessing the changing trend in heat, relative humidity and land surface temperature along with day and night time temperatures is necessary to develop a comprehensive heat management plan for the urban centres. This is needed to implement emergency measures during heatwaves to protect public health, and also to develop longer term strategies to mitigate heat by increasing green areas and waterbodies, improving thermal comfort in buildings, and reducing waste heat from vehicles, air-conditioners and industries”. According to the study, cities in the warm-humid and moderate climate zones show an increase, while cities in composite and hot-dry climate zones indicate a decline. Ambient air temperature has changed by less than 0.5°C between 2001-10 and 2014-23. Decadal summer-time average ambient temperature has risen by about 0.5°C in Mumbai, Bengaluru and Chennai compared with 2001-10. Kolkata’s decadal average is also up by 0.2°C. Delhi and Hyderabad, two metros which are located in composite climate zones known for the driest and harshest summers, have registered lower decadal average compared with 2001-10, the study adds. Decadal summer-time average for Delhi is down by 0.6°C and for Hyderabad, by 0.9°C, compared with 2001-10. “Addressing the combination of high heat and humidity is particularly important as this can compromise the human body’s main cooling mechanism: sweating. The evaporation of sweat from skin cools our bodies, but higher humidity levels limit this natural cooling. As a result, people can suffer heat stress and illness, and the consequences can even be fatal even at much lower ambient temperatures. Interestingly, night time temperature is remaining elevated in cities,” Avikal Somvanshi, senior programme manager, Urban Lab, CSE said in a statement related to the study’s release. Relative humidity has increased in all zones. This increase has made heat stress worse in warm-humid and moderate climate zones, while it has nullified the fall in air temperatures in composite and hot-dry climate zones, especially during monsoons. Average relative humidity (RH) has significantly increased in the last 10 summers compared with the 2001-10 average, the study noted. Barring Bengaluru, decadal summer-time average RH has increased by 5-10% in the other five mega cities, it added. The CSE study said that given the rise of relative humidity during summers, the heat index (HI) has risen among mega cities. Chennai´s summer average heat index stood at 37.4°C (impact of humidity: 6.9°C) making it the hottest among the mega cities. Kolkata with a summer HI average of 36.5°C (impact of humidity: 6.4°C) and Mumbai with 34.3°C (impact of humidity: 5°C) were almost equally hot. Delhi’s summer HI average stood at 32.2°C (impact of humidity: 3.3°C) and Hyderabad’s at 29.3°C (impact of humidity: 1.2°C). Bengaluru was the least hot among the mega cities with a summer HI average of 26.9°C (impact of humidity: 0.8°C). The study noted that monsoons were more thermally uncomfortable in Delhi, Mumbai, Kolkata and Chennai with their heat index being higher than during pre-monsoon period. Besides, cities are not cooling down at night at the rate they used to during 2001-10: This phenomena has been observed across all climatic zones. During the summers of 2001-10, land surface temperatures used to drop by 6.2°C-13.2°C from the day-time peak. Hyderabad used to cool down at night the most, while Kolkata the least. Now, in the last 10 summers (2014-23), night-time cooling has reduced to 6.2°C-11.5°C. The study noted that night-time cooling was getting lesser in the past few years for all megacities compared with the mid-2010s. “Hot nights are as dangerous as mid-day peak temperatures. People get little chance to recover from day-time heat if temperatures remain high overnight. A study published in the Lancet Planetary Health has noted that the risk of death from excessively hot nights would increase nearly six-fold in future. This prediction is much higher than the mortality risk from daily average warming suggested by climate change models,” said Somvanshi. The study also noted a direct co-relation between increase in built-up area and increase in urban heat stress. All megacities have become more concretised in the last two decades; this has contributed to the rise in heat stress; increase in green cover can moderate day-time heat, but is not that ineffective in arresting night-time heat. In 2023, Kolkata had the highest percentage of its land under concrete and the lowest green cover among the megacities; Delhi has comparatively the least area under concrete and the maximum green cover, it said. Over the past two decades, built-up area in Chennai has doubled. Kolkata has registered an only 10 percentage points increase in its built-up area, making it the slowest as far as concretisation is concerned. Hyderabad has doubled its green cover in the past two decades—fastest among the megacities. However, green cover has declined in Mumbai, Kolkata and Chennai. The maximum decline was noted in Chennai, whose green cover shrank by almost 14 percentage points, the CSE study said. The technical summary of the Intergovernmental Panel on Climate Change (IPCC), Working Group-I, Sixth Assessment Report (AR6 WG-I) notes that the frequency and intensity of heat extremes and duration of heat waves have almost certainly increased since 1950, and will keep rising even if global warming is stabilized at 1.5°C. The CSE study recommended implementation of city-specific heat management plans to go beyond immediate emergency responses to help cope with specific heat events during summer and prevent heat lock-in. Key heat generators, such as concrete built surfaces, barren land and waste heat generators like vehicles, industries, and cooling devices should be brought under the ambit of the plan. Guidelines and action plans to reduce thermal load on buildings and enhance thermal comfort; manage waste heat must be adopted. It also called for ensuring reversal of land-use changes to expand green areas and waterbodies for stronger cooling effect. Among the other recommendations are and increase in shaded areas. “There should be tracking of annual and diurnal trends in temperature, humidity and overall heat index to inform planning and implementation. It is critical to develop emergency healthcare systems for heat-related disease burden, expand the shaded areas in cities, ensure availability of drinking water in public spaces, and reduce heat exposure for vulnerable and occupationally exposed groups in cities,” the study added.

Bicycle-sharing, infrastructure make cycling a popular choice in China

On a May morning, in the Jianguomen area in the heart of Beijing, a father was teaching his son how to ride a bicycle, a mother and son duo came and parked their bicycles at a designated area, and a college student locked his bike using his smartphone after reaching his destination. “I use shareable bicycles every morning to go to my college. It’s easy and cheaper compared to cabs and is also environmentally friendly,” said Zhang Yi Fei, 23. Mr. Zhang is not alone and this trend is not limited to Jianguomen. Across Beijing, people riding blue, yellow and green bicycles are hard to miss and one can see dozens of bikes, at times hundreds, parked outside metro stations. These shareable bicycles belonging to three different private companies have made cycling hassle-free and popular. One can unlock a bicycle by scanning a QR code using a mobile app, ride it and park it at a different stand and pay using the same app. For example, from Jianguomen metro station to Ritan Park, which is less than 2 km, there are at least five cycle stands. It is 1.5 yuan (around Rs. 17) for a 30-minute ride and you can also take unlimited monthly or annual passes for as little as 17 and 200 yuan, respectively Liu Daizong, East Asia Director of the Institute for Transportation and Development Policy (ITDP), an international organisation that works with governments to design and implement transport and urban development systems, said he cycles to and from work every day using shareable bicycles. “It takes me about 45 minutes to ride 10 km to work in the morning and it is one of the best ways to commute in Beijing and it is a good exercise, too. Increasing number of people are using cycles in Beijing and people’s mindset towards cycling is also changing,” Mr. Liu said. Infrastructure push The popularity of cycling is not just because of bicycle-sharing, but also due to the infrastructure provided for cyclists. In Beijing, there are separate bicycle lanes in most parts of the city. These lanes are marked on the main road by intermittent broad red stripes on the right side of the road or large white signs of cycle. The government has built a 6.5-km dedicated three-lane bicycle track in the northwest part of the city, which is 6 metres wide. About 3 km of this is an elevated bicycle lane that runs over the main roads. It connects the Huilongguan area, where housing is comparatively cheaper, with the Shangdi area, which hosts many technology companies. In another part of the city, there are separate traffic lights for cycles and they turn green before other vehicles get a green signal, making it easier for cyclists. Mr. Liu, of the ITDP, said it is being run on a pilot basis. Not just Beijing Cycle lanes are not limited to Beijing. In different cities of Fujian and Hainan, two coastal provinces in the southeast and south of China, bicycle-sharing is picking up and cycle lanes are seen. But there are problems, too. An increasing number of electric scooters/bikes use the cycle lanes and whoosh past cyclists at higher speeds. In Xiamen, a city in Fujian, cycle tracks were seen on the sidewalks and not on the main road like in Beijing. Sometimes the tracks were not marked separately on the sidewalks, leading to pedestrians, cycles, and electric bikes, sharing the same space. In Quanzhou, a smaller city of Fujian, there were cycle tracks on the road and shareable bicycles. But without a subway network like Beijing and Xiamen, very few people were seen using shareable bicycles in the city. Due to differences in social and economic backgrounds, there is a significant disparity in the levels of bicycle ridership and development between cities in northern and southern China, according to the ITDP. Bumpy ride Interestingly, China’s bicycle journey over the years has not been a smooth one. “In the 1960s, owning a bicycle means you were rich and it was like owning a car today,” said Mr. Liu. But by the 1980s, it would not be uncommon to see thousands of cyclists, rather than cars, crowd the streets of major cities during the rush hour commute, and China was often recognised as the ‘Kingdom of Bicycles’, according to the ITDP. “But in the early 1990s, the number of buses on the roads increased and in the later half of 1990s, the number of cars also grew. The government encouraged people to buy cars, as the government thought it would lead to economic progress. China was trying to adopt the U.S. model of economic development,” Mr. Liu said. A 2004 article published by the state-run China Daily, titled “China ends bicycle kingdom as embracing cars”, speaks about how more people were buying cars. Mr. Liu said that slowly the number of cycles fell and people started associating cars with economic progress and success, while cycles were seen as only for the poor. “In Beijing, cars started to drive on the bicycle lanes and no one was monitoring them. The overall experience of cycling became bad. In my hometown Nanjing, authorities put the cycle lane in the pedestrian way,” added Mr. Liu. But air pollution and traffic congestion became a problem in many cities. “When China hosted the Olympics in 2008, factories were shut down for a month in Beijing to show the world that the air was clean,” Mr. Liu said. After the Olympics, people started demanding permanent solutions and the government also started seriously looking for solutions. “After Xi Jinping became President in 2012, the government took many concrete steps and pumped in more money and cycles were seen as a solution to both the problems,” he added. But in the early 2010s, bicycle-sharing started becoming popular. By 2016, there were too many private companies providing shareable bicycles. Bicycles were dumped in the streets, and in 2017, the government stepped in to regulate them. “By the end of 2017, 90% of these private companies went bankrupt and what we are seeing now are the ones who survived and the second generation of shareable bicycles,” Mr. Liu said. Mr. Liu said people’s mindset is also changing and since COVID-19, more people have taken up cycling. Bicycles are also part of Mr. Xi’s “Healthy China 2030” policy. “China still needs more infrastructure for bicycles and can learn from cities such as Copenhagen and Paris. But China can also be a model for many other countries,” he said. Lessons for India In Delhi, there are hardly any bicycle lanes, an issue which has been highlighted over the years by urban planners and cyclists, and people rarely use bicycles for last mile connectivity. Anumita Roychowdhury, executive director of the Centre for Science and Environment (CSE), a research and advocacy organisation in Delhi, said that though the idea of bicycle sharing has taken root in many Indian cities, it is still in the initial stages. Ms. Roychowdhury said that in Delhi, cycle lanes are fragmented small stretches that make up just 1% of the total road network. “It is largely for beautification and doesn’t meet the requirements of a commuter,” she said. “In India, mostly those from lower income groups cycle. Not many people cycle by choice, as the roads are unsafe for cyclists. Safety is a key factor when you decide whether you should cycle or not,” she added. Ms. Roychowdhury said there are policies in Delhi and other cities for including cycles and pedestrians in urban planning, but those are not being implemented properly. “We talk about sustainable transport, but government agencies are focussing mostly only on the main carriageway, which is meant for vehicles and not for cycles and pedestrians.” She stressed that promoting cycles and walking is crucial for solving air pollution in Delhi and other Indian cities. “Prioritising walking and cycling are the most fundamental zero emission strategies. But because of the obsession with car-centric planning, investments for walking and cycling are not happening and the infrastructure for it is not developing,” she added.

Why is Kolkata not cooling down even at night? Blame it on the heat island effect

KOLKATA: With the monsoon still a few days away, Kolkatans are enduring a pressure cooker feel during day with relative humidity hovering around 90% and maximum temperature touching 37°C. There is no relief from the sweltering heat at night either as heat island effect is preventing the city from cooling down adequately even after sunset. The real feel temperature in Kolkata was a scorching 50°C on Friday. A study by environment NGO Centre for Science & Environment (CSE) has observed that Kolkata is not cooling down at night as it used to during the first decade of the century. “Increase in built-up area, loss of greenery and reduction in water bodies has resulted in Kolkata losing its night-time cooling power,” said Avikal Sombanshi of CSE’s Urban Lab. Experts say the effect of urban heat islands is stronger at night than during day. A CSE study has found that drop in night-time land surface temperature (LST) is the lowest in core Kolkata areas that extend from Dum Dum in the north to Garia in the south. The average LST between March 1 and Aug 30 for 2018 to 2023 dropped from 32.5°C during the day to 25.8°C at night in the city core, from 31.6°C to 25°C in the outer city and 30.7°C to 24.6°C in periurban areas beyond Singur and Ashok Nagar in the north and Diamond Harbour and Kharagpur in the south. Rise in built-up area and loss of green cover and water bodies have intensified the urban heat island effect in Kolkata. The city’s built-up area, that stood at 70% of total area in 2001, has increased to 80.1% in 2023, the highest among metros. Consequently, green cover has reduced to 15.2% of total area in 2001 to 14.5% in 2023, the lowest among metros. In the same period, water bodies has decreased from 5.1% of total area to just 1.9%. ‘Heat index in Kolkata higher during monsoon’ A study by environment NGO Centre for Science and Environment (CSE) says urban heat island effect can add up to 2°C to local warming, reducing the adaptive capacity of a city. “The combination of high heat and humidity can compromise the human body’s main cooling mechanism: sweating. The evaporation of sweat from the skin cools our bodies, but higher humidity levels limit the natural cooling. As a result, people can suffer heat stress and illness, and the consequences can be fatal even at much lower temperatures if humidity is so high,” said Avikal Sombanshi. In the last decade, Kolkata experienced the highest relative humidity among six megacities in India. The city had the highest relative humidity in 2020 and the lowest in 2023, but the ambient air temperature was highest in 2023 at 30.1°C. “The monsoon months are more thermally uncomfortable with their heat index being higher than the pre-monsoon period,” said Ranjneesh Sareen of CSE. “IMD trend analysis showed evidence of an increase in air moisture content over India during 1969-2007 with more than 90% stations showing increasing trends in specific humidity. Thus the current wave of heat and humidity is in line of the Sixth Assessment Report of Working Group-I (AR6WGI) of IPCC, which says that the frequency and intensity of heat extremes and duration of heat waves have increased since 1950 and this will keep increasing even if global warming stabilises at 1.5°C,” said CSE executive director Anumita Roychowdhury.

印度城市高温多人死亡：普通人有多难熬

印度城市高温多人死亡：普通人有多难熬 来源：三联生活周刊 5月下旬，印度北部遭受持续高温天气，5月29日德里市区录得创纪录的49.1摄氏度。极端高温造成印度211人身亡。印度气象学家的研究显示，城市建设带来的环境变化，正在抬高城市的体感温度，让更多人面临健康挑战。 停电的不眠夜 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。 《睡在我上铺的兄弟》剧照 从五月中旬开始，由于用电需求暴涨，跳闸断电成了常态，尤其是晚上家家户户打开空调的时候。“一到晚上睡觉的时候就疯狂停电，这谁受的了？白天哪怕50度，只要不在室外挨晒，我可以在室内工作，但是我不能晚上40度在室内睡觉。” 李梓硕所在的学生公寓没有窗户，靠空调通风换气，一旦空调停摆，热气就凝滞在房间和楼道里。“只剩下洗澡这种方式来降温，让水蒸发带走热量。”但是在一室一卫的房间里，“一洗澡，整个屋湿度直线飙升，没有电用不了排风扇，等于让房间更热了，没过多久又得去洗。”李梓硕算过，最多一晚上洗了8次澡。 一般来说，电力会在一小时左右恢复。但是29日这天，电迟迟不来。在天台上，李梓硕试着闭上眼睡一会儿，但没有凉风，暑热令人辗转反侧，“根本睡不着”。直到天上的云渐渐显出轮廓，李梓硕才意识到一整夜就这么熬过去了。等到早上10点，烈日当空，电力供应才终于恢复。这天李梓硕要准备一门课的期末答辩，但是通宵失眠让他感觉“很虚，恍惚和亢奋交替”。 当地时间5月29日，印度德里有气温监测站记录到49.1摄氏度高温。有一座监测站曾测出52.9摄氏度高温，但印度政府在6月1日澄清，该温度传感器出现故障。49.1摄氏度的高温打破了此前德里辖区的最高温纪录。1998年，德里的气温曾经达到过48.4度。 这场极端热浪还赶上印度五年一度的大选。6月1日，大选投票进入最后阶段，不少民众顶着酷热前往投票站排队，有人在队伍中晕倒。据《印度时报》报道，截至6月3日，印度全国已有211人疑似因中暑身亡，其中包括33名选举现场当值的工作人员。新闻网站ThePrint援引政府数据称，3月至5月，印度共有近2.5万人疑似中暑。 当地时间2024年5月22日，各地市民在酷暑下参与政选活动（图源｜视觉中国） 在德里做电子产品销售的李成，每周上6天班，要四处跑客户。他用“榨油”来形容白天呆在户外的感受。“下午12点到6点之间，温度基本都在 45 度左右，人像在炉子里，穿短袖露出的手臂直冒汗，但又不像汗，像被榨出来的油。”李成告诉本刊，他最近每天都要喝三五升的水，此外还要靠印度传统冷饮补充盐分和糖分。“那是一种柠檬水，加了很多玛萨拉（香料），咸咸的，虽然喝完胃有点不舒服，但是解渴，而且喝完有体力，不会像喝白水一样，喝完有虚脱的感觉。” 最热的那两天，李成出现了疑似中暑症状。“出差的地方没空调，两点半我准备睡觉，但睡不着，爬起来喝了四次水。尽管如此，一夜没有去过洗手间，水分全都出汗出掉了。我全身都被汗湿透，连整个枕头浸湿了。”第二天，李成觉得自己好像感冒了，吃了一天感冒药，“浑浑噩噩，到了有空调的地方才缓过气来。” 《我是余欢水》剧照 对于在读研究生李梓硕来说，白天只要避免户外运动，勉强能撑过去。他会坐公交车到有空调的高级商场去，找一家咖啡馆坐上一天，因为那是城中少数供电稳定的地方。经过德里街头，李梓硕发现面熟的几个流浪汉不再沿街乞讨，而是从早到晚都躺在地上，“感觉已经没有力气了”。街道清洁人员在恶劣天气下也难以持续工作，垃圾堆放在街道上两三天也没人移走，异味极为强烈。不过，李梓硕觉得今年蚊子格外少，“好像减少了90%”。 城市升温 德里不是突然一下子热起来的。位于印度北部的德里有超过2千万人口，范围涵盖首都区新德里，属于热带季风气候，初夏总会干燥炎热，直到季风来临的雨季才会好转。往年4到6月，德里的平均气温在38摄氏度左右，出现45摄氏度的高温也不出奇。所以，德里居民早就养成了一些应对高温的习惯，比如使用水和风扇组合成的“水空调”，食用高盐分的食物，以及推迟睡眠时间。 不过，今年比往年更难熬，不仅气温高，而且超40摄氏度的天数是往年同期的两倍，习惯了酷暑的德里居民也开始受不了。去年刚来德里上学的时候，李梓硕注意到，他的印度同学不像中国男生，再热也不会在宿舍脱掉上衣。但今年，“印度同学也都开始赤膊在宿舍走动了。” 据印度科学媒体《自然印度》报道，今年的极端高温，最直接原因是厄尔尼诺现象导致海洋温度上升，而来自孟加拉湾和阿拉伯海的潮湿海风被高压系统挡住。 不过，印度科学家发现，如果把时间拉长到近20年，印度城市温度整体升高与城市化的热岛效应也脱离不了干系——由于地表、建筑、植被和人类活动的不同，城市比周边地区更热。印度理工学院布巴内斯瓦尔分校的地球、海洋与气候科学学院副教授V·维诺杰(V. Vinoj )今年5月发表了一篇论文，指出热岛效应对于印度城市气温升高的作用，可能占到60%。 维诺杰和同事进行的这项研究，分析了2003年到2020年印度141座城市的温度变化。他们发现，城市的环境温度平均每十年升高0.5摄氏度，是全国平均值的2倍，而且城市的变暖幅度远大于它们周边的乡村。经济和人口规模处在第二梯队的新兴城市，因为发展速度快，气温受城市化影响也最明显，个别城市升温甚至100%来自热岛效应——在所处地域普遍降温的情况下，这座城市仍反向升温。 印度新德里遭热浪侵袭 民众“挤爆”市政水车取水（图源｜视觉中国） 事实上，影响人们体感的，还不单纯是气象站探测到的温度。印度研究机构科学与环境中心（CSE）的数据显示，印度大城市体感温度的上升，远远快于环境升温速度，这主要是因为空气更湿了，以及夜间温度降不下来。 CSE的报告称，比起10年前，2023年德里的夏季平均气温变化幅度不到1摄氏度，但体感温度增加了3.3摄氏度，湿度增加了8%。CSE高级研究员、城市环境学家阿维卡尔·索姆万什（Avikal Somvanshi）告诉本刊，湿度升高对于干热的印度北部来讲，不是好消息。“人体通过排出汗液、水分蒸发来达到降温的目的，但是当相对湿度较高时，水分的蒸发率就会降低，体感会更热。” 夜间高温则是另一个棘手问题。“以前德里市区入夜后可以下降13、14度，现在只会下降8、9度。”这意味着，夜晚温度也将保持在40度以上。索姆万什说，“比起工作状态，睡眠需要更低的温度。如果夜间温度过高，人体将无法从炎热白天的疲劳中恢复，如果连续三四天都是如此，身体健康会受到明显影响。” 索姆万什表示，科学家们对于印度北部的湿度为何增加尚不清楚，但可以肯定的是，夜间高温与城市的“混凝土化”有关。“德里的老房子，通常有更厚的墙壁，阻隔烈日。这些墙壁用泥土和石头建造，散热快，而且会有很多通风设计，能够让微风穿过房子。但是随着城市发展，越来越多建筑采用水泥、玻璃建造的外墙，而些材质不利于散热，到了晚上把热气锁在室内，室内比室外更热。空调虽然能把热气从室内带走，但是这会加剧室外的高温，那些没有空调的人就遭殃了。” 如何“降温” 气候变暖的大背景下，城市和乡村面临着不同挑战。索姆万什说，“尽管城市有更多的经济资源和基础设施，空调覆盖率也更高，但城市比乡村至少热上2到3度，有时甚至高出5、6度，而且城市人口要密集得多。此外，城市里的快递员、外卖员、维修工，他们受到酷热影响的风险，远远大于乡村里从事类似行业的人。” 根据世界银行2022年的数据，印度有大约5亿人居住在城市，占总人口36%，而这个比重还在增加。如何应对越来越常见的城市高温风险，成了印度科学家们关注的问题。 维诺杰在接受本刊采访时说，他希望自己的研究能提醒人们，虽然全球气候变化是个宏观问题，但是从改善城市的“小气候”入手，是切实可行的。“比起干预全球变暖，改变城市的局部温度，成本要低得多，而且对人们的生活影响更直观——水泥结构和绿地造成的温度差别是可计算的，把深色的建筑刷成白色，也能带来明显的降温效果。政策制定者能够很轻易地从数据中，量化这些措施带来的回报。” 印度新德里持续遭遇高温天气 民众拎“大盆小罐”排队接水（图源｜视觉中国） “过去许多年，印度在城市建设上喜欢赶时髦。我们会听到官员说伦敦是怎么建的、上海是怎么建的，我们也要建成那样。虽然看起来富丽堂皇，但是有些建筑形制其实不适合我们本地的气候。”索姆万什说，德里还有许多建筑在翻新和重建，在接下来的建设中，更多地考量气候和环境因素，是缓解城市高温的关键。 除了城市建设，公共政策也有很多调整的余地。索姆万什说，“我们的劳动法需要改变。如今印度的许多工作单位没有午休。但在最热的午后时间，专注工作几乎成了不可能的事。”据世界银行估计，印度近75%的劳动力，即3.8亿人，依赖于暴露在高温下的劳动，这些人面临着极高的健康风险，以及工作放缓带来的收入锐减。 当地时间2024年5月30日，印度瓦拉纳西，医生正在检查一名中暑患者。（图源｜视觉中国） 家在印度南部的学生，暑假通常选择回家避暑，但李梓硕的选项不多。当被问到接下来如何度过这个夏天，李梓硕回答：“最主要是忍”。 索姆万什说，对于普通人来讲，除非能换个地方生活，否则尝试从衣着、饮食和作息上，适应高温这种新常态，也许是眼下能做的事。 “气候变暖是一个不可逆的过程。即便我们遏制住恶化的趋势，也意味着今天我们面对的高温，恐怕还将持续。”

印度城市高温多人死亡：49度天气普通人有多难熬？

*本文为「三联生活周刊」原创内容 5月下旬，印度北部遭受持续高温天气，5月29日德里市区录得创纪录的49.1摄氏度。极端高温造成印度211人身亡。印度气象学家的研究显示，城市建设带来的环境变化，正在抬高城市的体感温度，让更多人面临健康挑战。 记者｜覃思 编辑｜徐菁菁 停电的不眠夜 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。 《睡在我上铺的兄弟》剧照 从五月中旬开始，由于用电需求暴涨，跳闸断电成了常态，尤其是晚上家家户户打开空调的时候。“一到晚上睡觉的时候就疯狂停电，这谁受的了？白天哪怕50度，只要不在室外挨晒，我可以在室内工作，但是我不能晚上40度在室内睡觉。” 李梓硕所在的学生公寓没有窗户，靠空调通风换气，一旦空调停摆，热气就凝滞在房间和楼道里。“只剩下洗澡这种方式来降温，让水蒸发带走热量。”但是在一室一卫的房间里，“一洗澡，整个屋湿度直线飙升，没有电用不了排风扇，等于让房间更热了，没过多久又得去洗。”李梓硕算过，最多一晚上洗了8次澡。 一般来说，电力会在一小时左右恢复。但是29日这天，电迟迟不来。在天台上，李梓硕试着闭上眼睡一会儿，但没有凉风，暑热令人辗转反侧，“根本睡不着”。直到天上的云渐渐显出轮廓，李梓硕才意识到一整夜就这么熬过去了。等到早上10点，烈日当空，电力供应才终于恢复。这天李梓硕要准备一门课的期末答辩，但是通宵失眠让他感觉“很虚，恍惚和亢奋交替”。 当地时间5月29日，印度德里有气温监测站记录到49.1摄氏度高温。有一座监测站曾测出52.9摄氏度高温，但印度政府在6月1日澄清，该温度传感器出现故障。49.1摄氏度的高温打破了此前德里辖区的最高温纪录。1998年，德里的气温曾经达到过48.4度。 这场极端热浪还赶上印度五年一度的大选。6月1日，大选投票进入最后阶段，不少民众顶着酷热前往投票站排队，有人在队伍中晕倒。据《印度时报》报道，截至6月3日，印度全国已有211人疑似因中暑身亡，其中包括33名选举现场当值的工作人员。新闻网站ThePrint援引政府数据称，3月至5月，印度共有近2.5万人疑似中暑。 当地时间2024年5月22日，各地市民在酷暑下参与政选活动（图源｜视觉中国） 在德里做电子产品销售的李成，每周上6天班，要四处跑客户。他用“榨油”来形容白天呆在户外的感受。“下午12点到6点之间，温度基本都在 45 度左右，人像在炉子里，穿短袖露出的手臂直冒汗，但又不像汗，像被榨出来的油。”李成告诉本刊，他最近每天都要喝三五升的水，此外还要靠印度传统冷饮补充盐分和糖分。“那是一种柠檬水，加了很多玛萨拉（香料），咸咸的，虽然喝完胃有点不舒服，但是解渴，而且喝完有体力，不会像喝白水一样，喝完有虚脱的感觉。” 最热的那两天，李成出现了疑似中暑症状。“出差的地方没空调，两点半我准备睡觉，但睡不着，爬起来喝了四次水。尽管如此，一夜没有去过洗手间，水分全都出汗出掉了。我全身都被汗湿透，连整个枕头浸湿了。”第二天，李成觉得自己好像感冒了，吃了一天感冒药，“浑浑噩噩，到了有空调的地方才缓过气来。” 《我是余欢水》剧照 对于在读研究生李梓硕来说，白天只要避免户外运动，勉强能撑过去。他会坐公交车到有空调的高级商场去，找一家咖啡馆坐上一天，因为那是城中少数供电稳定的地方。经过德里街头，李梓硕发现面熟的几个流浪汉不再沿街乞讨，而是从早到晚都躺在地上，“感觉已经没有力气了”。街道清洁人员在恶劣天气下也难以持续工作，垃圾堆放在街道上两三天也没人移走，异味极为强烈。不过，李梓硕觉得今年蚊子格外少，“好像减少了90%”。 城市升温 德里不是突然一下子热起来的。位于印度北部的德里有超过2千万人口，范围涵盖首都区新德里，属于热带季风气候，初夏总会干燥炎热，直到季风来临的雨季才会好转。往年4到6月，德里的平均气温在38摄氏度左右，出现45摄氏度的高温也不出奇。所以，德里居民早就养成了一些应对高温的习惯，比如使用水和风扇组合成的“水空调”，食用高盐分的食物，以及推迟睡眠时间。 不过，今年比往年更难熬，不仅气温高，而且超40摄氏度的天数是往年同期的两倍，习惯了酷暑的德里居民也开始受不了。去年刚来德里上学的时候，李梓硕注意到，他的印度同学不像中国男生，再热也不会在宿舍脱掉上衣。但今年，“印度同学也都开始赤膊在宿舍走动了。” 据印度科学媒体《自然印度》报道，今年的极端高温，最直接原因是厄尔尼诺现象导致海洋温度上升，而来自孟加拉湾和阿拉伯海的潮湿海风被高压系统挡住。 不过，印度科学家发现，如果把时间拉长到近20年，印度城市温度整体升高与城市化的热岛效应也脱离不了干系——由于地表、建筑、植被和人类活动的不同，城市比周边地区更热。印度理工学院布巴内斯瓦尔分校的地球、海洋与气候科学学院副教授V·维诺杰(V. Vinoj )今年5月发表了一篇论文，指出热岛效应对于印度城市气温升高的作用，可能占到60%。 维诺杰和同事进行的这项研究，分析了2003年到2020年印度141座城市的温度变化。他们发现，城市的环境温度平均每十年升高0.5摄氏度，是全国平均值的2倍，而且城市的变暖幅度远大于它们周边的乡村。经济和人口规模处在第二梯队的新兴城市，因为发展速度快，气温受城市化影响也最明显，个别城市升温甚至100%来自热岛效应——在所处地域普遍降温的情况下，这座城市仍反向升温。 印度新德里遭热浪侵袭 民众“挤爆”市政水车取水（图源｜视觉中国） 事实上，影响人们体感的，还不单纯是气象站探测到的温度。印度研究机构科学与环境中心（CSE）的数据显示，印度大城市体感温度的上升，远远快于环境升温速度，这主要是因为空气更湿了，以及夜间温度降不下来。 CSE的报告称，比起10年前，2023年德里的夏季平均气温变化幅度不到1摄氏度，但体感温度增加了3.3摄氏度，湿度增加了8%。CSE高级研究员、城市环境学家阿维卡尔·索姆万什（Avikal Somvanshi）告诉本刊，湿度升高对于干热的印度北部来讲，不是好消息。“人体通过排出汗液、水分蒸发来达到降温的目的，但是当相对湿度较高时，水分的蒸发率就会降低，体感会更热。” 夜间高温则是另一个棘手问题。“以前德里市区入夜后可以下降13、14度，现在只会下降8、9度。”这意味着，夜晚温度也将保持在40度以上。索姆万什说，“比起工作状态，睡眠需要更低的温度。如果夜间温度过高，人体将无法从炎热白天的疲劳中恢复，如果连续三四天都是如此，身体健康会受到明显影响。” 索姆万什表示，科学家们对于印度北部的湿度为何增加尚不清楚，但可以肯定的是，夜间高温与城市的“混凝土化”有关。“德里的老房子，通常有更厚的墙壁，阻隔烈日。这些墙壁用泥土和石头建造，散热快，而且会有很多通风设计，能够让微风穿过房子。但是随着城市发展，越来越多建筑采用水泥、玻璃建造的外墙，而些材质不利于散热，到了晚上把热气锁在室内，室内比室外更热。空调虽然能把热气从室内带走，但是这会加剧室外的高温，那些没有空调的人就遭殃了。” 如何“降温” 气候变暖的大背景下，城市和乡村面临着不同挑战。索姆万什说，“尽管城市有更多的经济资源和基础设施，空调覆盖率也更高，但城市比乡村至少热上2到3度，有时甚至高出5、6度，而且城市人口要密集得多。此外，城市里的快递员、外卖员、维修工，他们受到酷热影响的风险，远远大于乡村里从事类似行业的人。” 根据世界银行2022年的数据，印度有大约5亿人居住在城市，占总人口36%，而这个比重还在增加。如何应对越来越常见的城市高温风险，成了印度科学家们关注的问题。 维诺杰在接受本刊采访时说，他希望自己的研究能提醒人们，虽然全球气候变化是个宏观问题，但是从改善城市的“小气候”入手，是切实可行的。“比起干预全球变暖，改变城市的局部温度，成本要低得多，而且对人们的生活影响更直观——水泥结构和绿地造成的温度差别是可计算的，把深色的建筑刷成白色，也能带来明显的降温效果。政策制定者能够很轻易地从数据中，量化这些措施带来的回报。” 印度新德里持续遭遇高温天气 民众拎“大盆小罐”排队接水（图源｜视觉中国） “过去许多年，印度在城市建设上喜欢赶时髦。我们会听到官员说伦敦是怎么建的、上海是怎么建的，我们也要建成那样。虽然看起来富丽堂皇，但是有些建筑形制其实不适合我们本地的气候。”索姆万什说，德里还有许多建筑在翻新和重建，在接下来的建设中，更多地考量气候和环境因素，是缓解城市高温的关键。 除了城市建设，公共政策也有很多调整的余地。索姆万什说，“我们的劳动法需要改变。如今印度的许多工作单位没有午休。但在最热的午后时间，专注工作几乎成了不可能的事。”据世界银行估计，印度近75%的劳动力，即3.8亿人，依赖于暴露在高温下的劳动，这些人面临着极高的健康风险，以及工作放缓带来的收入锐减。 当地时间2024年5月30日，印度瓦拉纳西，医生正在检查一名中暑患者。（图源｜视觉中国） 家在印度南部的学生，暑假通常选择回家避暑，但李梓硕的选项不多。当被问到接下来如何度过这个夏天，李梓硕回答：“最主要是忍”。 索姆万什说，对于普通人来讲，除非能换个地方生活，否则尝试从衣着、饮食和作息上，适应高温这种新常态，也许是眼下能做的事。 “气候变暖是一个不可逆的过程。即便我们遏制住恶化的趋势，也意味着今天我们面对的高温，恐怕还将持续。” “点赞”“在看”，让更多人看到

印度城市高温多人死亡：49度天气普通人有多难熬？

5月下旬，印度北部遭受持续高温天气，5月29日德里市区录得创纪录的49.1摄氏度。极端高温造成印度211人身亡。印度气象学家的研究显示，城市建设带来的环境变化，正在抬高城市的体感温度，让更多人面临健康挑战。 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。 《睡在我上铺的兄弟》剧照 从五月中旬开始，由于用电需求暴涨，跳闸断电成了常态，尤其是晚上家家户户打开空调的时候。“一到晚上睡觉的时候就疯狂停电，这谁受的了？白天哪怕50度，只要不在室外挨晒，我可以在室内工作，但是我不能晚上40度在室内睡觉。” 李梓硕所在的学生公寓没有窗户，靠空调通风换气，一旦空调停摆，热气就凝滞在房间和楼道里。“只剩下洗澡这种方式来降温，让水蒸发带走热量。”但是在一室一卫的房间里，“一洗澡，整个屋湿度直线飙升，没有电用不了排风扇，等于让房间更热了，没过多久又得去洗。”李梓硕算过，最多一晚上洗了8次澡。 一般来说，电力会在一小时左右恢复。但是29日这天，电迟迟不来。在天台上，李梓硕试着闭上眼睡一会儿，但没有凉风，暑热令人辗转反侧，“根本睡不着”。直到天上的云渐渐显出轮廓，李梓硕才意识到一整夜就这么熬过去了。等到早上10点，烈日当空，电力供应才终于恢复。这天李梓硕要准备一门课的期末答辩，但是通宵失眠让他感觉“很虚，恍惚和亢奋交替”。 当地时间5月29日，印度德里有气温监测站记录到49.1摄氏度高温。有一座监测站曾测出52.9摄氏度高温，但印度政府在6月1日澄清，该温度传感器出现故障。49.1摄氏度的高温打破了此前德里辖区的最高温纪录。1998年，德里的气温曾经达到过48.4度。 这场极端热浪还赶上印度五年一度的大选。6月1日，大选投票进入最后阶段，不少民众顶着酷热前往投票站排队，有人在队伍中晕倒。据《印度时报》报道，截至6月3日，印度全国已有211人疑似因中暑身亡，其中包括33名选举现场当值的工作人员。新闻网站ThePrint援引政府数据称，3月至5月，印度共有近2.5万人疑似中暑。 当地时间2024年5月22日，各地市民在酷暑下参与政选活动（图源｜视觉中国） 在德里做电子产品销售的李成，每周上6天班，要四处跑客户。他用“榨油”来形容白天呆在户外的感受。“下午12点到6点之间，温度基本都在 45 度左右，人像在炉子里，穿短袖露出的手臂直冒汗，但又不像汗，像被榨出来的油。”李成告诉本刊，他最近每天都要喝三五升的水，此外还要靠印度传统冷饮补充盐分和糖分。“那是一种柠檬水，加了很多玛萨拉（香料），咸咸的，虽然喝完胃有点不舒服，但是解渴，而且喝完有体力，不会像喝白水一样，喝完有虚脱的感觉。” 最热的那两天，李成出现了疑似中暑症状。“出差的地方没空调，两点半我准备睡觉，但睡不着，爬起来喝了四次水。尽管如此，一夜没有去过洗手间，水分全都出汗出掉了。我全身都被汗湿透，连整个枕头浸湿了。”第二天，李成觉得自己好像感冒了，吃了一天感冒药，“浑浑噩噩，到了有空调的地方才缓过气来。” 《我是余欢水》剧照 对于在读研究生李梓硕来说，白天只要避免户外运动，勉强能撑过去。他会坐公交车到有空调的高级商场去，找一家咖啡馆坐上一天，因为那是城中少数供电稳定的地方。经过德里街头，李梓硕发现面熟的几个流浪汉不再沿街乞讨，而是从早到晚都躺在地上，“感觉已经没有力气了”。街道清洁人员在恶劣天气下也难以持续工作，垃圾堆放在街道上两三天也没人移走，异味极为强烈。不过，李梓硕觉得今年蚊子格外少，“好像减少了90%”。 城市升温 德里不是突然一下子热起来的。位于印度北部的德里有超过2千万人口，范围涵盖首都区新德里，属于热带季风气候，初夏总会干燥炎热，直到季风来临的雨季才会好转。往年4到6月，德里的平均气温在38摄氏度左右，出现45摄氏度的高温也不出奇。所以，德里居民早就养成了一些应对高温的习惯，比如使用水和风扇组合成的“水空调”，食用高盐分的食物，以及推迟睡眠时间。 不过，今年比往年更难熬，不仅气温高，而且超40摄氏度的天数是往年同期的两倍，习惯了酷暑的德里居民也开始受不了。去年刚来德里上学的时候，李梓硕注意到，他的印度同学不像中国男生，再热也不会在宿舍脱掉上衣。但今年，“印度同学也都开始赤膊在宿舍走动了。” 据印度科学媒体《自然印度》报道，今年的极端高温，最直接原因是厄尔尼诺现象导致海洋温度上升，而来自孟加拉湾和阿拉伯海的潮湿海风被高压系统挡住。 不过，印度科学家发现，如果把时间拉长到近20年，印度城市温度整体升高与城市化的热岛效应也脱离不了干系——由于地表、建筑、植被和人类活动的不同，城市比周边地区更热。印度理工学院布巴内斯瓦尔分校的地球、海洋与气候科学学院副教授V·维诺杰(V. Vinoj )今年5月发表了一篇论文，指出热岛效应对于印度城市气温升高的作用，可能占到60%。 维诺杰和同事进行的这项研究，分析了2003年到2020年印度141座城市的温度变化。他们发现，城市的环境温度平均每十年升高0.5摄氏度，是全国平均值的2倍，而且城市的变暖幅度远大于它们周边的乡村。经济和人口规模处在第二梯队的新兴城市，因为发展速度快，气温受城市化影响也最明显，个别城市升温甚至100%来自热岛效应——在所处地域普遍降温的情况下，这座城市仍反向升温。 印度新德里遭热浪侵袭 民众“挤爆”市政水车取水（图源｜视觉中国） 事实上，影响人们体感的，还不单纯是气象站探测到的温度。印度研究机构科学与环境中心（CSE）的数据显示，印度大城市体感温度的上升，远远快于环境升温速度，这主要是因为空气更湿了，以及夜间温度降不下来。 CSE的报告称，比起10年前，2023年德里的夏季平均气温变化幅度不到1摄氏度，但体感温度增加了3.3摄氏度，湿度增加了8%。CSE高级研究员、城市环境学家阿维卡尔·索姆万什（Avikal Somvanshi）告诉本刊，湿度升高对于干热的印度北部来讲，不是好消息。“人体通过排出汗液、水分蒸发来达到降温的目的，但是当相对湿度较高时，水分的蒸发率就会降低，体感会更热。” 夜间高温则是另一个棘手问题。“以前德里市区入夜后可以下降13、14度，现在只会下降8、9度。”这意味着，夜晚温度也将保持在40度以上。索姆万什说，“比起工作状态，睡眠需要更低的温度。如果夜间温度过高，人体将无法从炎热白天的疲劳中恢复，如果连续三四天都是如此，身体健康会受到明显影响。” 索姆万什表示，科学家们对于印度北部的湿度为何增加尚不清楚，但可以肯定的是，夜间高温与城市的“混凝土化”有关。“德里的老房子，通常有更厚的墙壁，阻隔烈日。这些墙壁用泥土和石头建造，散热快，而且会有很多通风设计，能够让微风穿过房子。但是随着城市发展，越来越多建筑采用水泥、玻璃建造的外墙，而些材质不利于散热，到了晚上把热气锁在室内，室内比室外更热。空调虽然能把热气从室内带走，但是这会加剧室外的高温，那些没有空调的人就遭殃了。” 如何“降温” 气候变暖的大背景下，城市和乡村面临着不同挑战。索姆万什说，“尽管城市有更多的经济资源和基础设施，空调覆盖率也更高，但城市比乡村至少热上2到3度，有时甚至高出5、6度，而且城市人口要密集得多。此外，城市里的快递员、外卖员、维修工，他们受到酷热影响的风险，远远大于乡村里从事类似行业的人。” 根据世界银行2022年的数据，印度有大约5亿人居住在城市，占总人口36%，而这个比重还在增加。如何应对越来越常见的城市高温风险，成了印度科学家们关注的问题。 维诺杰在接受本刊采访时说，他希望自己的研究能提醒人们，虽然全球气候变化是个宏观问题，但是从改善城市的“小气候”入手，是切实可行的。“比起干预全球变暖，改变城市的局部温度，成本要低得多，而且对人们的生活影响更直观——水泥结构和绿地造成的温度差别是可计算的，把深色的建筑刷成白色，也能带来明显的降温效果。政策制定者能够很轻易地从数据中，量化这些措施带来的回报。” 印度新德里持续遭遇高温天气 民众拎“大盆小罐”排队接水（图源｜视觉中国） “过去许多年，印度在城市建设上喜欢赶时髦。我们会听到官员说伦敦是怎么建的、上海是怎么建的，我们也要建成那样。虽然看起来富丽堂皇，但是有些建筑形制其实不适合我们本地的气候。”索姆万什说，德里还有许多建筑在翻新和重建，在接下来的建设中，更多地考量气候和环境因素，是缓解城市高温的关键。 除了城市建设，公共政策也有很多调整的余地。索姆万什说，“我们的劳动法需要改变。如今印度的许多工作单位没有午休。但在最热的午后时间，专注工作几乎成了不可能的事。”据世界银行估计，印度近75%的劳动力，即3.8亿人，依赖于暴露在高温下的劳动，这些人面临着极高的健康风险，以及工作放缓带来的收入锐减。 当地时间2024年5月30日，印度瓦拉纳西，医生正在检查一名中暑患者。（图源｜视觉中国） 家在印度南部的学生，暑假通常选择回家避暑，但李梓硕的选项不多。当被问到接下来如何度过这个夏天，李梓硕回答：“最主要是忍”。 索姆万什说，对于普通人来讲，除非能换个地方生活，否则尝试从衣着、饮食和作息上，适应高温这种新常态，也许是眼下能做的事。 “气候变暖是一个不可逆的过程。即便我们遏制住恶化的趋势，也意味着今天我们面对的高温，恐怕还将持续。” “点赞”“在看”，让更多人看到 排版：初初 / 审核：杨逸

印度现50℃高温,已有211人被热死!首都居民:没法住(图)

每年的夏天，印度都伴随着高温，从3月持续到9月，高温天气将持续半年。但没有一个夏天，像今年这样难熬。 43°C，45°C，48°C，49.9°C，每一天都在刷新历史最高温度，这是印度有史以来最热的一个夏天。如果持续下去，气温将达到人类生存的极限。 在这个常住人口2900 多万的印度首都里，缺水情况非常严重，许多地方一滴水都没有了。印度人民正在渡劫。 01 印度最热一天 印度首都新德里，一辆水车驶入拥挤的街区，人群爆发了一阵骚动。数十名居民疯狂追赶水车，挥舞着水桶、瓶子和软管，有些甚至跳到水车顶上，誓要取完最后一滴水。 当天，新德里气温飙升至 49 ℃，这是有记录以来新德里最热的一天。 每天早上，住在维维卡南德营地贫困飞地的社会卫生工作者特里皮（Tripti）都要提着水桶和水壶站在烈日下，焦急等待运水车的到来。 特里皮说：“为了打几桶水，我们必须排2-3小时的队。但气温还在不断升高，这无疑是雪上加霜。天气越来越热，需要的水越来越多，但供应量却在不断减少。我们承受着高温的痛苦，几乎无法活下去。” 炎热是新德里的常客。在这里，夏天常常是闷热的，富人们待在家里吹空调，而穷人只能聚集在风扇下，用湿抹布降温。 5月份的热浪席卷了印度北部的大部分地区，近一周的气温常常超过45 ℃，数百万居民表示难以忍受。因为从事户外建筑或劳动工作，有一些人无法为自己降温，几乎要失去生命。 5月29日，印度德里地区蒙盖什布尔气温监测站记录到52.9℃高温，创下德里地区最高气温纪录。随后官方表示，52.9℃的高温数字有误，实际最高温度为49.9℃。 专家和居民一致认为，因为印度首当其冲地受到气候危机的影响，所以今年夏季的印度气温远远高于正常水平。 热岛效应 但除了气候危机的影响，城市“热岛效应”也在加剧持续高温天气。 印度环境学家Avikal Somvanshi 表示：“二十年前，印度早晚温差约为 12 摄氏度或更高，但现在的新德里不可能再有这么大的昼夜温差。” 他表示，新德里生活着太多的人，人们无限压缩绿化面积建造混凝土建筑，来缓解拥挤不堪的空间。 但这样的钢铁森林，加剧了城市热岛效应。 由于城市建筑和道路使用了大量的混凝土、沥青等材料这些材料的热容量大，吸热能力强导致热量积累。 其次，城市中的绿地面积相对较小，植被覆盖不足以通过蒸发和光合作用有效降温。 所以在夏季高峰期，这座城市的昼夜温差，不会超过 6 到 7 摄氏度。 《柳叶刀》发表的研究显示，夜晚炎热的日子，人们的死亡风险提高了 50%。 6月3日消息，过去24小时内，印度奥里萨邦至少有45人死于可能与炎热有关的疾病。截至目前，印度全国因炎热死亡人数上升至211人。 此外，印度媒体还透露，目前中暑和因中暑死亡人数上报有滞后性，实际死亡人数可能远远超过官方政府公布数据。 持续多日的高温还赶上印度大选。5月25日和6月1日，印度大选分别举行第六阶段和第七阶段的投票，据媒体报道，北方邦6月1日投票期间有至少33名选举工作人员因中暑而死亡，死者包括安保和卫生保洁人员。 03 贫富同此凉热 此外，由于数百万富人使用空调，新德里各地长时间停电，导致电力需求达到历史新高，情况更加恶化。 热浪影响了电力变压器，甚至有电力变压器因高温起火。 新德里消防局局长表示，他每天能接到200多个火灾电话，这是过去十年来的最高水平。 5 岁的尼廷-辛格（Nitin Singh）是一名律师，居住在拉杰帕特纳加尔（Lajpat Nagar）社区，他讲述了每天停电给他和年幼的孩子以及 81 岁患病的父亲带来的毁灭性影响。他说，自从高温来袭，新德里已变得 “无法居住”。 “我家有三台空调，但停电让我束手无策，”辛格说， “昨晚停电了两个小时，我为生病的父亲和孩子们在酒店开了一间房。我和妻子在家里的阳台上过了大半夜，但好几个小时难以入睡。” 37 岁的穆罕默德-阿什拉夫-汗（Mohammad Ashraf Khan）在奥克拉（Okhla）地区经营着一家空调出租店，他说，自从气温超过 45 摄氏度后，他的电话都快被打出火来了。通常他每个季节出租 80 台空调，但今年的需求增加到 130 台。 “今年关于空调过热和故障的投诉越来越多，”他说，“极端高温使普通空调也无法满足降温需要。” 04 明天会好吗？ 然而在印度，空调终究是一种奢侈品。 一名在新德里工厂工作的 40 岁农民工，死于高温。上周三，他的体温超出正常水平 5 ℃，随后死亡。 他的医生告诉媒体：“他住在一个没有冷风机或风扇的房间里，因为发高烧......他的体温飙升到 41.5 ℃以上。” 在新德里南部的一个居民区，尼莎-阿加瓦尔（Nisha Aggarwal）还在遵守一个古老的传统，在自家门外的人行道上放置装满水的大陶罐，让路人解渴。普通夏天，她家的保安每天只用给水壶加一次水，但 “过去两周天气太热了，他每天都要给水壶加好几次水”，她说。 新德里政府也表示，它们已成立了“酷暑作战室”，将向缺水地区派遣水罐车。 保安普罗比尔·拉姆 (Probir Ram) 还在烈日下工作。虽然他要求在闷热的保安室里装一个饮水机，但遭到了雇主的拒绝。拉姆浑身大汗，衬衫湿透了，看上去十分痛苦。 他叹了口气说： “我知道高温还会持续下去，但像我这样人，只会最早一批死去。除此之外，我们还有什么办法呢？” 高温 居民 印度

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停电的不眠夜 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏 后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了 天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分 散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是 因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。

印度城市高温多人死亡：普通人有多难熬

5月下旬，印度北部遭受持续高温天气，5月29日德里市区录得创纪录的49.1摄氏度。极端高温造成印度211人身亡。印度气象学家的研究显示，城市建设带来的环境变化，正在抬高城市的体感温度，让更多人面临健康挑战。 停电的不眠夜 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。 从五月中旬开始，由于用电需求暴涨，跳闸断电成了常态，尤其是晚上家家户户打开空调的时候。“一到晚上睡觉的时候就疯狂停电，这谁受的了？白天哪怕50度，只要不在室外挨晒，我可以在室内工作，但是我不能晚上40度在室内睡觉。” 李梓硕所在的学生公寓没有窗户，靠空调通风换气，一旦空调停摆，热气就凝滞在房间和楼道里。“只剩下洗澡这种方式来降温，让水蒸发带走热量。”但是在一室一卫的房间里，“一洗澡，整个屋湿度直线飙升，没有电用不了排风扇，等于让房间更热了，没过多久又得去洗。”李梓硕算过，最多一晚上洗了8次澡。 一般来说，电力会在一小时左右恢复。但是29日这天，电迟迟不来。在天台上，李梓硕试着闭上眼睡一会儿，但没有凉风，暑热令人辗转反侧，“根本睡不着”。直到天上的云渐渐显出轮廓，李梓硕才意识到一整夜就这么熬过去了。等到早上10点，烈日当空，电力供应才终于恢复。这天李梓硕要准备一门课的期末答辩，但是通宵失眠让他感觉“很虚，恍惚和亢奋交替”。 当地时间5月29日，印度德里有气温监测站记录到49.1摄氏度高温。有一座监测站曾测出52.9摄氏度高温，但印度政府在6月1日澄清，该温度传感器出现故障。49.1摄氏度的高温打破了此前德里辖区的最高温纪录。1998年，德里的气温曾经达到过48.4度。 这场极端热浪还赶上印度五年一度的大选。6月1日，大选投票进入最后阶段，不少民众顶着酷热前往投票站排队，有人在队伍中晕倒。据《印度时报》报道，截至6月3日，印度全国已有211人疑似因中暑身亡，其中包括33名选举现场当值的工作人员。新闻网站ThePrint援引政府数据称，3月至5月，印度共有近2.5万人疑似中暑。 当地时间2024年5月22日，各地市民在酷暑下参与政选活动（图源｜视觉中国） 在德里做电子产品销售的李成，每周上6天班，要四处跑客户。他用“榨油”来形容白天呆在户外的感受。“下午12点到6点之间，温度基本都在 45 度左右，人像在炉子里，穿短袖露出的手臂直冒汗，但又不像汗，像被榨出来的油。”李成告诉本刊，他最近每天都要喝三五升的水，此外还要靠印度传统冷饮补充盐分和糖分。“那是一种柠檬水，加了很多玛萨拉（香料），咸咸的，虽然喝完胃有点不舒服，但是解渴，而且喝完有体力，不会像喝白水一样，喝完有虚脱的感觉。” 最热的那两天，李成出现了疑似中暑症状。“出差的地方没空调，两点半我准备睡觉，但睡不着，爬起来喝了四次水。尽管如此，一夜没有去过洗手间，水分全都出汗出掉了。我全身都被汗湿透，连整个枕头浸湿了。”第二天，李成觉得自己好像感冒了，吃了一天感冒药，“浑浑噩噩，到了有空调的地方才缓过气来。” 对于在读研究生李梓硕来说，白天只要避免户外运动，勉强能撑过去。他会坐公交车到有空调的高级商场去，找一家咖啡馆坐上一天，因为那是城中少数供电稳定的地方。经过德里街头，李梓硕发现面熟的几个流浪汉不再沿街乞讨，而是从早到晚都躺在地上，“感觉已经没有力气了”。街道清洁人员在恶劣天气下也难以持续工作，垃圾堆放在街道上两三天也没人移走，异味极为强烈。不过，李梓硕觉得今年蚊子格外少，“好像减少了90%”。 城市升温 德里不是突然一下子热起来的。位于印度北部的德里有超过2千万人口，范围涵盖首都区新德里，属于热带季风气候，初夏总会干燥炎热，直到季风来临的雨季才会好转。往年4到6月，德里的平均气温在38摄氏度左右，出现45摄氏度的高温也不出奇。所以，德里居民早就养成了一些应对高温的习惯，比如使用水和风扇组合成的“水空调”，食用高盐分的食物，以及推迟睡眠时间。 不过，今年比往年更难熬，不仅气温高，而且超40摄氏度的天数是往年同期的两倍，习惯了酷暑的德里居民也开始受不了。去年刚来德里上学的时候，李梓硕注意到，他的印度同学不像中国男生，再热也不会在宿舍脱掉上衣。但今年，“印度同学也都开始赤膊在宿舍走动了。” 据印度科学媒体《自然印度》报道，今年的极端高温，最直接原因是厄尔尼诺现象导致海洋温度上升，而来自孟加拉湾和阿拉伯海的潮湿海风被高压系统挡住。 不过，印度科学家发现，如果把时间拉长到近20年，印度城市温度整体升高与城市化的热岛效应也脱离不了干系——由于地表、建筑、植被和人类活动的不同，城市比周边地区更热。印度理工学院布巴内斯瓦尔分校的地球、海洋与气候科学学院副教授V·维诺杰(V. Vinoj )今年5月发表了一篇论文，指出热岛效应对于印度城市气温升高的作用，可能占到60%。 维诺杰和同事进行的这项研究，分析了2003年到2020年印度141座城市的温度变化。他们发现，城市的环境温度平均每十年升高0.5摄氏度，是全国平均值的2倍，而且城市的变暖幅度远大于它们周边的乡村。经济和人口规模处在第二梯队的新兴城市，因为发展速度快，气温受城市化影响也最明显，个别城市升温甚至100%来自热岛效应——在所处地域普遍降温的情况下，这座城市仍反向升温。 印度新德里遭热浪侵袭 民众“挤爆”市政水车取水（图源｜视觉中国） 事实上，影响人们体感的，还不单纯是气象站探测到的温度。印度研究机构科学与环境中心（CSE）的数据显示，印度大城市体感温度的上升，远远快于环境升温速度，这主要是因为空气更湿了，以及夜间温度降不下来。 CSE的报告称，比起10年前，2023年德里的夏季平均气温变化幅度不到1摄氏度，但体感温度增加了3.3摄氏度，湿度增加了8%。CSE高级研究员、城市环境学家阿维卡尔·索姆万什（Avikal Somvanshi）告诉本刊，湿度升高对于干热的印度北部来讲，不是好消息。“人体通过排出汗液、水分蒸发来达到降温的目的，但是当相对湿度较高时，水分的蒸发率就会降低，体感会更热。” 夜间高温则是另一个棘手问题。“以前德里市区入夜后可以下降13、14度，现在只会下降8、9度。”这意味着，夜晚温度也将保持在40度以上。索姆万什说，“比起工作状态，睡眠需要更低的温度。如果夜间温度过高，人体将无法从炎热白天的疲劳中恢复，如果连续三四天都是如此，身体健康会受到明显影响。” 索姆万什表示，科学家们对于印度北部的湿度为何增加尚不清楚，但可以肯定的是，夜间高温与城市的“混凝土化”有关。“德里的老房子，通常有更厚的墙壁，阻隔烈日。这些墙壁用泥土和石头建造，散热快，而且会有很多通风设计，能够让微风穿过房子。但是随着城市发展，越来越多建筑采用水泥、玻璃建造的外墙，而些材质不利于散热，到了晚上把热气锁在室内，室内比室外更热。空调虽然能把热气从室内带走，但是这会加剧室外的高温，那些没有空调的人就遭殃了。” 如何“降温” 气候变暖的大背景下，城市和乡村面临着不同挑战。索姆万什说，“尽管城市有更多的经济资源和基础设施，空调覆盖率也更高，但城市比乡村至少热上2到3度，有时甚至高出5、6度，而且城市人口要密集得多。此外，城市里的快递员、外卖员、维修工，他们受到酷热影响的风险，远远大于乡村里从事类似行业的人。” 根据世界银行2022年的数据，印度有大约5亿人居住在城市，占总人口36%，而这个比重还在增加。如何应对越来越常见的城市高温风险，成了印度科学家们关注的问题。 维诺杰在接受本刊采访时说，他希望自己的研究能提醒人们，虽然全球气候变化是个宏观问题，但是从改善城市的“小气候”入手，是切实可行的。“比起干预全球变暖，改变城市的局部温度，成本要低得多，而且对人们的生活影响更直观——水泥结构和绿地造成的温度差别是可计算的，把深色的建筑刷成白色，也能带来明显的降温效果。政策制定者能够很轻易地从数据中，量化这些措施带来的回报。” 印度新德里持续遭遇高温天气 民众拎“大盆小罐”排队接水（图源｜视觉中国） “过去许多年，印度在城市建设上喜欢赶时髦。我们会听到官员说伦敦是怎么建的、上海是怎么建的，我们也要建成那样。虽然看起来富丽堂皇，但是有些建筑形制其实不适合我们本地的气候。”索姆万什说，德里还有许多建筑在翻新和重建，在接下来的建设中，更多地考量气候和环境因素，是缓解城市高温的关键。 除了城市建设，公共政策也有很多调整的余地。索姆万什说，“我们的劳动法需要改变。如今印度的许多工作单位没有午休。但在最热的午后时间，专注工作几乎成了不可能的事。”据世界银行估计，印度近75%的劳动力，即3.8亿人，依赖于暴露在高温下的劳动，这些人面临着极高的健康风险，以及工作放缓带来的收入锐减。 当地时间2024年5月30日，印度瓦拉纳西，医生正在检查一名中暑患者。（图源｜视觉中国） 家在印度南部的学生，暑假通常选择回家避暑，但李梓硕的选项不多。当被问到接下来如何度过这个夏天，李梓硕回答：“最主要是忍”。 索姆万什说，对于普通人来讲，除非能换个地方生活，否则尝试从衣着、饮食和作息上，适应高温这种新常态，也许是眼下能做的事。 “气候变暖是一个不可逆的过程。即便我们遏制住恶化的趋势，也意味着今天我们面对的高温，恐怕还将持续。”

印度城市高温多人死亡：49度天气普通人有多难熬？

5月下旬，印度北部遭受持续高温天气，5月29日德里市区录得创纪录的49.1摄氏度。极端高温造成印度211人身亡。印度气象学家的研究显示，城市建设带来的环境变化，正在抬高城市的体感温度，让更多人面临健康挑战。 5月29日星期三夜晚，印度德里市区有史以来最热的一天，留学生李梓硕经历了入夏后最漫长的一次停电。 停电是从凌晨12点开始的。等待来电的李梓硕，跟住在隔壁的同学一起爬楼梯上了天台。午夜，室外温度仍高达40度，但和室内相比，那里至少不闷。两人用聊天分散着停电带来的烦躁。恰逢期末考试周，同学告诉李梓硕，他一共有7门考试，但是因为天热，连续一周没能睡好觉，头疼，已经考砸了一科。 从五月中旬开始，由于用电需求暴涨，跳闸断电成了常态，尤其是晚上家家户户打开空调的时候。“一到晚上睡觉的时候就疯狂停电，这谁受的了？白天哪怕50度，只要不在室外挨晒，我可以在室内工作，但是我不能晚上40度在室内睡觉。” 李梓硕所在的学生公寓没有窗户，靠空调通风换气，一旦空调停摆，热气就凝滞在房间和楼道里。“只剩下洗澡这种方式来降温，让水蒸发带走热量。”但是在一室一卫的房间里，“一洗澡，整个屋湿度直线飙升，没有电用不了排风扇，等于让房间更热了，没过多久又得去洗。”李梓硕算过，最多一晚上洗了8次澡。 一般来说，电力会在一小时左右恢复。但是29日这天，电迟迟不来。在天台上，李梓硕试着闭上眼睡一会儿，但没有凉风，暑热令人辗转反侧，“根本睡不着”。直到天上的云渐渐显出轮廓，李梓硕才意识到一整夜就这么熬过去了。等到早上10点，烈日当空，电力供应才终于恢复。这天李梓硕要准备一门课的期末答辩，但是通宵失眠让他感觉“很虚，恍惚和亢奋交替”。 当地时间5月29日，印度德里有气温监测站记录到49.1摄氏度高温。有一座监测站曾测出52.9摄氏度高温，但印度政府在6月1日澄清，该温度传感器出现故障。49.1摄氏度的高温打破了此前德里辖区的最高温纪录。1998年，德里的气温曾经达到过48.4度。 这场极端热浪还赶上印度五年一度的大选。6月1日，大选投票进入最后阶段，不少民众顶着酷热前往投票站排队，有人在队伍中晕倒。据《印度时报》报道，截至6月3日，印度全国已有211人疑似因中暑身亡，其中包括33名选举现场当值的工作人员。新闻网站ThePrint援引政府数据称，3月至5月，印度共有近2.5万人疑似中暑。 当地时间2024年5月22日，各地市民在酷暑下参与政选活动（图源｜视觉中国） 在德里做电子产品销售的李成，每周上6天班，要四处跑客户。他用“榨油”来形容白天呆在户外的感受。“下午12点到6点之间，温度基本都在 45 度左右，人像在炉子里，穿短袖露出的手臂直冒汗，但又不像汗，像被榨出来的油。”李成告诉本刊，他最近每天都要喝三五升的水，此外还要靠印度传统冷饮补充盐分和糖分。“那是一种柠檬水，加了很多玛萨拉（香料），咸咸的，虽然喝完胃有点不舒服，但是解渴，而且喝完有体力，不会像喝白水一样，喝完有虚脱的感觉。” 最热的那两天，李成出现了疑似中暑症状。“出差的地方没空调，两点半我准备睡觉，但睡不着，爬起来喝了四次水。尽管如此，一夜没有去过洗手间，水分全都出汗出掉了。我全身都被汗湿透，连整个枕头浸湿了。”第二天，李成觉得自己好像感冒了，吃了一天感冒药，“浑浑噩噩，到了有空调的地方才缓过气来。” 《我是余欢水》剧照 对于在读研究生李梓硕来说，白天只要避免户外运动，勉强能撑过去。他会坐公交车到有空调的高级商场去，找一家咖啡馆坐上一天，因为那是城中少数供电稳定的地方。经过德里街头，李梓硕发现面熟的几个流浪汉不再沿街乞讨，而是从早到晚都躺在地上，“感觉已经没有力气了”。街道清洁人员在恶劣天气下也难以持续工作，垃圾堆放在街道上两三天也没人移走，异味极为强烈。不过，李梓硕觉得今年蚊子格外少，“好像减少了90%”。 城市升温 德里不是突然一下子热起来的。位于印度北部的德里有超过2千万人口，范围涵盖首都区新德里，属于热带季风气候，初夏总会干燥炎热，直到季风来临的雨季才会好转。往年4到6月，德里的平均气温在38摄氏度左右，出现45摄氏度的高温也不出奇。所以，德里居民早就养成了一些应对高温的习惯，比如使用水和风扇组合成的“水空调”，食用高盐分的食物，以及推迟睡眠时间。 不过，今年比往年更难熬，不仅气温高，而且超40摄氏度的天数是往年同期的两倍，习惯了酷暑的德里居民也开始受不了。去年刚来德里上学的时候，李梓硕注意到，他的印度同学不像中国男生，再热也不会在宿舍脱掉上衣。但今年，“印度同学也都开始赤膊在宿舍走动了。” 据印度科学媒体《自然印度》报道，今年的极端高温，最直接原因是厄尔尼诺现象导致海洋温度上升，而来自孟加拉湾和阿拉伯海的潮湿海风被高压系统挡住。 不过，印度科学家发现，如果把时间拉长到近20年，印度城市温度整体升高与城市化的热岛效应也脱离不了干系——由于地表、建筑、植被和人类活动的不同，城市比周边地区更热。印度理工学院布巴内斯瓦尔分校的地球、海洋与气候科学学院副教授V·维诺杰(V. Vinoj )今年5月发表了一篇论文，指出热岛效应对于印度城市气温升高的作用，可能占到60%。 维诺杰和同事进行的这项研究，分析了2003年到2020年印度141座城市的温度变化。他们发现，城市的环境温度平均每十年升高0.5摄氏度，是全国平均值的2倍，而且城市的变暖幅度远大于它们周边的乡村。经济和人口规模处在第二梯队的新兴城市，因为发展速度快，气温受城市化影响也最明显，个别城市升温甚至100%来自热岛效应——在所处地域普遍降温的情况下，这座城市仍反向升温。 印度新德里遭热浪侵袭 民众“挤爆”市政水车取水（图源｜视觉中国） 事实上，影响人们体感的，还不单纯是气象站探测到的温度。印度研究机构科学与环境中心（CSE）的数据显示，印度大城市体感温度的上升，远远快于环境升温速度，这主要是因为空气更湿了，以及夜间温度降不下来。 CSE的报告称，比起10年前，2023年德里的夏季平均气温变化幅度不到1摄氏度，但体感温度增加了3.3摄氏度，湿度增加了8%。CSE高级研究员、城市环境学家阿维卡尔·索姆万什（Avikal Somvanshi）告诉本刊，湿度升高对于干热的印度北部来讲，不是好消息。“人体通过排出汗液、水分蒸发来达到降温的目的，但是当相对湿度较高时，水分的蒸发率就会降低，体感会更热。” 夜间高温则是另一个棘手问题。“以前德里市区入夜后可以下降13、14度，现在只会下降8、9度。”这意味着，夜晚温度也将保持在40度以上。索姆万什说，“比起工作状态，睡眠需要更低的温度。如果夜间温度过高，人体将无法从炎热白天的疲劳中恢复，如果连续三四天都是如此，身体健康会受到明显影响。” 索姆万什表示，科学家们对于印度北部的湿度为何增加尚不清楚，但可以肯定的是，夜间高温与城市的“混凝土化”有关。“德里的老房子，通常有更厚的墙壁，阻隔烈日。这些墙壁用泥土和石头建造，散热快，而且会有很多通风设计，能够让微风穿过房子。但是随着城市发展，越来越多建筑采用水泥、玻璃建造的外墙，而些材质不利于散热，到了晚上把热气锁在室内，室内比室外更热。空调虽然能把热气从室内带走，但是这会加剧室外的高温，那些没有空调的人就遭殃了。” 如何“降温” 气候变暖的大背景下，城市和乡村面临着不同挑战。索姆万什说，“尽管城市有更多的经济资源和基础设施，空调覆盖率也更高，但城市比乡村至少热上2到3度，有时甚至高出5、6度，而且城市人口要密集得多。此外，城市里的快递员、外卖员、维修工，他们受到酷热影响的风险，远远大于乡村里从事类似行业的人。” 根据世界银行2022年的数据，印度有大约5亿人居住在城市，占总人口36%，而这个比重还在增加。如何应对越来越常见的城市高温风险，成了印度科学家们关注的问题。 维诺杰在接受本刊采访时说，他希望自己的研究能提醒人们，虽然全球气候变化是个宏观问题，但是从改善城市的“小气候”入手，是切实可行的。“比起干预全球变暖，改变城市的局部温度，成本要低得多，而且对人们的生活影响更直观——水泥结构和绿地造成的温度差别是可计算的，把深色的建筑刷成白色，也能带来明显的降温效果。政策制定者能够很轻易地从数据中，量化这些措施带来的回报。” 印度新德里持续遭遇高温天气 民众拎“大盆小罐”排队接水（图源｜视觉中国） “过去许多年，印度在城市建设上喜欢赶时髦。我们会听到官员说伦敦是怎么建的、上海是怎么建的，我们也要建成那样。虽然看起来富丽堂皇，但是有些建筑形制其实不适合我们本地的气候。”索姆万什说，德里还有许多建筑在翻新和重建，在接下来的建设中，更多地考量气候和环境因素，是缓解城市高温的关键。 除了城市建设，公共政策也有很多调整的余地。索姆万什说，“我们的劳动法需要改变。如今印度的许多工作单位没有午休。但在最热的午后时间，专注工作几乎成了不可能的事。”据世界银行估计，印度近75%的劳动力，即3.8亿人，依赖于暴露在高温下的劳动，这些人面临着极高的健康风险，以及工作放缓带来的收入锐减。 当地时间2024年5月30日，印度瓦拉纳西，医生正在检查一名中暑患者。（图源｜视觉中国） 家在印度南部的学生，暑假通常选择回家避暑，但李梓硕的选项不多。当被问到接下来如何度过这个夏天，李梓硕回答：“最主要是忍”。 索姆万什说，对于普通人来讲，除非能换个地方生活，否则尝试从衣着、饮食和作息上，适应高温这种新常态，也许是眼下能做的事。 “气候变暖是一个不可逆的过程。即便我们遏制住恶化的趋势，也意味着今天我们面对的高温，恐怕还将持续。”