{
  "$type": "site.standard.document",
  "bskyPostRef": {
    "cid": "bafyreiatiplvatnvwxx4hqpl5sbifvxstv27gntncqo23zqpnke76cxgti",
    "uri": "at://did:plc:qdzcgmgri7npfs46puqpnnjo/app.bsky.feed.post/3mnjaaaoax4i2"
  },
  "coverImage": {
    "$type": "blob",
    "ref": {
      "$link": "bafkreigpqziq3ilwuzsh7hlhs2jyjvetxp3y2jtmmuop3a3ukasvtul2ce"
    },
    "mimeType": "image/webp",
    "size": 55744
  },
  "path": "/news/2005340/worsening-urban-heat-could-trigger-public-health-meltdown-expert-warns",
  "publishedAt": "2026-06-05T03:44:00.000Z",
  "site": "https://www.dawn.com",
  "tags": [
    "Newspaper"
  ],
  "textContent": "**• Cites 2026 study that finds Karachi has highest urban-rural temperature difference\n• Says emergency response not enough, the city must reduce heat at its source\n• Links pollution, dense construction, traffic, and tree loss to growing health risks**\n\nKARACHI: Highlighting the multiple environmental challenges Karachi faces, a senior community health sciences expert has called for urgent actions at both the government and individual levels to tackle the growing urban heat problem that’s silently damaging public health and productivity.\n\nResponding to _Dawn_ ’s queries about Karachi’s challenges on the eve of World Environment Day, Prof Zafar Fatmi, Head of Environmental Occupational Health and Climate Change at the Department of Community Health Sciences, Aga Khan University, said that the city’s urban heat effect appears to be becoming more intense.\n\n“This is not only because of global climate change, but also because of how the city is growing, how people move through it, how much pollution they breathe, and how little protection many people have while working and living outdoors,” shared Prof Fatmi, who has done several studies on subjects related to community health.\n\nHe explained that more concrete, more roads, high-density construction, traffic congestion, loss of trees, and fewer open spaces are making the city absorb and retain more heat.\n\nReferring to studies conducted from Karachi, he said that they showed that urban heat island effects are present, with higher night-time land surface temperatures in urban areas, and recent work has identified heatwave vulnerability in the city’s dense urban zones.\n\n“A 2026 multi-city Pakistan study also found that Karachi has the highest urban-rural temperature difference among major cities studied, around 4.5°C, and linked vegetation loss with higher land surface temperature.\n\n“This means Karachi is not only experiencing hotter weather; it is also being built in a way that makes heat worse. In our own microscale urban heat work in Karachi [a 2024 study], we found that delivery riders and rickshaw drivers experienced temperatures much higher than the city’s recorded average,” he said.\n\nThe study published two years ago showed that in summer, exposure was about 5.5°C higher under direct sun and 1.8°C higher even in shade compared with the city average.\n\n“This tells us something very important: the heat people face on the street is often different from the official temperature. The real exposure is what people feel at traffic signals, bus stops, roadside markets, construction sites, school routes, and while travelling for work.”\n\nResponding to a question about warning signs of growing intensity of urban heat, Pro Fatmi said that they are already visible; nights are not cooling adequately, outdoor workers feel exhausted earlier in the day and people complain of dehydration, headache, dizziness, poor sleep, fatigue, and fainting.\n\n“Those with heart disease, lung disease, hypertension, diabetes, kidney disease, and old age are at greater risk. Children, pregnant women, traffic police, vendors, construction workers, delivery riders, rickshaw drivers, and people living in poorly ventilated homes are particularly vulnerable.”\n\nUnderscoring the need for urgent action, he said that when ordinary places such as bus stops, traffic signals, roadside shops, and school routes become heat-risk zones, it is a sign that urban heat is no longer an occasional discomfort; it is becoming a public-health exposure.\n\nThe problem, he points out, becomes more serious when heat combines with air pollution. Karachi’s residents do not experience heat and pollution separately.\n\n“They breathe polluted air in hot, congested, dusty, and traffic-heavy conditions. Heat increases dehydration, breathing rate, and pressure on the heart, while air pollution affects the lungs, blood vessels, and cardiovascular system.”\n\nAccording to Prof Fatmi, research from hundreds of cities has shown that high temperatures can modify the health effects of air pollutants, including particulate matter, nitrogen dioxide, and ozone.\n\n“Other studies also suggest that combined exposure to heat and particulate pollution can increase mortality risk more than either exposure alone. For Karachi, this means air pollution control and heat planning should not be treated as separate issues.”\n\nReplying to a question whether there is a link between rising temperature, urban heat and infections, he explained that higher temperatures can create conditions in which some pathogens, mosquitoes, and contamination risks grow more easily, especially where water, sanitation, waste, and drainage systems are weak.\n\n“Food spoils faster. Stored water becomes unsafe more easily. Stagnant water can support mosquito breeding. Climate research shows that warming temperatures and changing rainfall patterns are affecting vector-borne diseases, while water-borne and food-borne infections can also increase where heat is combined with poor sanitation and unsafe water.”\n\nIn Karachi, therefore, he says, the risk is not heat alone; it is heat plus poor drainage, unsafe water storage, waste accumulation, crowding, and weak municipal services.\n\nOn the actions required at both individual and state levels, he said that people should avoid unnecessary outdoor exposure during peak heat, drink safe water frequently, use shade, cover the head, avoid heavy exertion during the hottest hours, and check on children, elderly people, pregnant women, and people with chronic diseases.\n\n“People should recognise early danger signs such as dizziness, confusion, fainting, severe weakness, very hot skin, or inability to drink water. Outdoor workers need shaded rest areas, drinking water, and adjusted work hours. These should be treated as basic occupational protections, not as charity.”\n\nAt the government level, he says, Karachi needs a serious heat-health action plan. “This should include simple public alerts in Urdu and local languages, shaded bus stops, public drinking-water points, cooling spaces, school guidance during heatwaves, emergency preparedness in hospitals, and legal protection for outdoor workers during extreme heat.”\n\nHowever, he emphasises that emergency response alone is not enough and that the city must also reduce heat at its source; protecting mature trees, expanding green and blue spaces, reducing unnecessary concrete, improving public transport, controlling dust and vehicle emissions, stopping waste burning, using cooler building and road materials, and making heat assessment mandatory for major roads, buildings, and infrastructure projects.\n\n“A climate-resilient Karachi will require health, planning, transport, environment, labour, and municipal authorities to work together. Otherwise, heat will continue to quietly damage health, productivity, and dignity, especially among the poor and those who work outdoors.”\n\n_Published in Dawn, June 5th, 2026_",
  "title": "Worsening urban heat could trigger public health meltdown, expert warns"
}