By Sudha Ramen
The week I sat down to write this piece from the UK, the country could not cope with its own weather. Having spent most of my life with the long summers of India, and now living through one in England, I find myself writing this essay less as speculation but as a lived experience. From my window in Oxford, I watched a society improvise its way through heat it was never designed or built for. England and Wales were living through the second record-breaking heatwave in a single summer — the first time since 1911 that two consecutive months had each broken a temperature record — and a rare Red extreme-heat warning hung over a band of the country stretching from London to Swansea.1 The June record fell, and then fell again: 36.7°C in a Somerset village one afternoon, 36.9°C in a Suffolk two days later, the hottest June day the United Kingdom has ever measured.1 Though not the hottest ever which remains the 40.3°C recorded in July 2022 — but a June that was never seen before.2
In Oxford and across the UK, most schools and nurseries closed, and popular libraries in Oxford shut their doors.3 In supermarkets from Oxfordshire to Sussex, the refrigeration simply gave out; staff drew curtains and sheets across the chilled aisles and taped up apologetic notes as the milk, meat and dairy were cordoned off behind them.4 Trains were ordered to reduce speed so the rails would not buckle; on one day alone some 2,600 services were cancelled or delayed.3 London’s ambulance crews answered 8,869 emergency calls in a single day — the busiest day in the service’s history, busier than the peak of the pandemic — and declared a critical incident overnight.5 And when the heat finally broke, it came in a different form, as thunderstorms and lightning that grounded and delayed hundreds of flights at Heathrow and Gatwick, some by close to six hours.6 Heat does not only bake; it destabilises into violence on its way out.
On the pavement in front of my residence, a man stood for a long while in the thin strip of shade thrown by an extended building sunshade, waiting for a breath of moving air that never arrived on the afternoon of a heatwave day.
Four and a half thousand miles away, in India, that same restlessness plays out every summer, only louder. In Mumbai, when the power fails, families spill out of their homes and walk towards the water. They go to Marine Drive and to the long grey beaches that line the Arabian Sea, hoping the sea will give some cool breeze. They get only a little respite, as the sea itself now runs a heavy fever.
These two scenes — a hushed English street and a crowded Indian shore — are the same story told by the media across two nations. Heat is no longer a seasonal effect; it has become a condition we now live with. And it does not treat us equally.
The same sun, but two unequal summers
In India, heat has quietly become a tax on the economy itself. The International Labour Organization estimates that, by 2030, the productivity lost to heat stress worldwide will be equivalent to 80 million full-time jobs — and India alone may account for around 34 million of them, because so much of its workforce labours outdoors or in buildings with no cooling.7 The World Bank has warned that lost labour hours could put up to 4.5 per cent of India’s GDP at risk by the end of this decade.8 The Lancet Countdown recorded roughly 167 billion potential labour hours lost to heat exposure in India in a single recent year, the burden falling heaviest on agriculture, and noted a 55 per cent rise in heat-related deaths there between the early 2000s and the early 2020s.9
The United Kingdom’s relationship with heat is not a recent phenomenon, but the intensity with which it now comes certainly is. This is a country built for cool — homes designed to trap warmth, offices with windows that barely open, a workforce that stays mostly indoors. So when the heat comes, it shakes every home. In the 2022 heatwave London first crossed 40°C; this year the capital broke its all-time May record at 35.1°C, before June broke its own record.2,10
In Britain the heat reached deep into ordinary life precisely because society let it: the school sent the children home, the supermarket sealed its aisles, the library locked up, the train stayed in the depot. A closed shop on a scorching afternoon, in the United Kingdom, simply stays closed with an apologetic note. In urban India it is almost unthinkable. The street vendor does not pull down the shutter, because the shutter coming down means no income that day, and for the daily-wage worker, the construction labourer, the delivery rider and the small unorganised business, there is no cushion under a lost day. So the work continues under the same scorching sun — the roadside stall stays open, the cement is still mixed, the parcel is still delivered — because the fear of going hungry is sharper than the fear of heatstroke. The same thermometer reading produces a shuttered street in one city and a crowded, sweltering one in the other. This is why we cannot measure the heat distress of two cities from two different geographies and two different economies on the same scale.
Thirty-five degrees in London is genuinely intolerable — its houses were built to hold warmth in, with little ventilation and almost no provision for cooling — yet the city manages to sustain it, partly because of passive cooling built into its very town planning: the parks and commons, the street trees, the rivers, ponds and canals that its councils maintain all year round, not as a heat measure but as ordinary urban fabric. India’s cities, by contrast, have been growing greyer and less green, and cooling tends to be spoken of only in the hot months — the year-round work that green and blue spaces quietly do, from cleaning the air to holding water to cooling the night, is undervalued the rest of the time.
There is a deeper asymmetry here, and it makes the divide worth understanding. The cost of maintaining passive cooling — the trees, the parks, the water bodies, the cool building design — does not fall on the individual. It rests with landowners, real-estate developers, institutions, and above all local bodies, and so it demands collective will, and often political will, to fund and sustain. Active cooling requires none of this collective effort. The air conditioner is a private purchase with a private bill, a decision one household can make alone. Faced with that choice, it is no wonder so many reach for the easy, individual fix. But when a whole city reaches for it at once, the grid is overloaded, the power fails — and the cooling that felt so private and so reliable vanishes for everyone at once, sending people back out into the streets and down to the shore in search of the older, passive cooling that was never protected. The heat divide between these two countries is less about temperature than about perspective and planning.
Heat is not felt the same way by everyone, even within a single country. The main reason is access to cooling, which comes in two forms. Active cooling — air conditioners, refrigerators, cold stores — needs reliable power and money. Passive cooling — shade, ventilation, light-coloured “cool” roofs, trees, parks and water — is what design and nature provide for free. The gap between the two is the divide that matters.
Both cities sort their people along that line, and those below the midpoint suffer the most. In London, extreme heat hits the most deprived communities hardest, and a severe heatwave sharpens that inequality into danger.10 In India the gap is even wider. Informal workers, the majority of the workforce, have no cooled workplaces and can lose up to 40 per cent of their income in a bad heatwave because the body cannot keep working.8 For them, air conditioning is not a rationed comfort; it is a world that remains largely out of reach.
Even the oldest passive cooling is failing. When the grid goes down, the coastal family’s last resort is the sea breeze — but the sea is warming. India’s ocean-information service reported in May that roughly a third of the Arabian Sea had entered marine-heatwave stress.11 A hotter sea returns warmer, more humid air, and humid heat is the more dangerous kind: sweat cannot evaporate, so those who go to the shore for relief mostly return more dehydrated.
A University of Oxford study this June ranked 205 cities of over a million people by heat risk and placed more than 95 per cent of the highest-risk cities in South and Southeast Asia and Sub-Saharan Africa — Ahmedabad second in the world, Nagpur fourth, Madurai seventh, fourteen Indian cities in the top fifty.12 What drives the risk, the authors stressed, is not heat itself but the absence of cooling and green buffers, and they warned against treating air conditioning as the answer. Geography deals these cities a poor hand; unplanned grey development and the loss of green cover make it far worse.
The heat is also set to rise. Forecasters now put the odds of an El Niño this summer at around 80 per cent, climbing above 90 per cent by autumn.13,14 El Niño raises global temperatures and warms the seas, so even the coast people flee to offers less relief.
A situation of a public-health emergency
Heat, a silent disaster until now, has moved to the mainstage as the number of victims grows across geographies. Across 854 European cities in the summer of 2025, scientists estimated that human-caused climate change was responsible for roughly two-thirds of about 24,400 heat deaths, with London among the hardest-hit cities; a closer study of one early-summer heatwave put the climate-driven toll at an additional 235 deaths in Paris and well over a hundred in London.15,16 Much of that urban toll traces to the heat-island effect, where concrete and asphalt hold the warmth long into the night.17 India’s count of heat victims stays lower not because the heat is milder, but because it is under-reported — heat is usually logged under a co-morbidity rather than named as the cause. When heat kills the elderly in a Paris apartment, an outdoor worker in Mumbai, and a roadside sleeper in London in the same season, it stops being a weather story and becomes a public-health emergency.
A call for collective action: break the silos
The heat divide is now a core subject at the major climate forums, and the response is beginning to take shape. London Climate Action Week, happening as I write, has placed sustainable, city-led cooling at the centre of its agenda, treating extreme heat as an economic and energy-security risk and not only an environmental one.18 Its discussions converge on a few points: that cooling should be treated as essential infrastructure, alongside water and energy; that the world cannot air-condition its way out, since most of the cooling needed can come from cheaper passive and low-energy measures; that action must be local, because it is councils that decide which street gets trees and which settlement gets a shelter; and that heat is, above all, an equity problem, falling first on the low-income, the elderly, the outdoor worker and the badly housed.18
That thinking is now backed by institutions, each within its sector. The UNEP-led Cool Coalition, with the COP30 Presidency, runs the Beat the Heat drive, which brings together more than 230 cities across 40-plus countries — 44 of them Indian — to assess heat risk and expand passive and nature-based cooling.19 Under the linked Global Cooling Pledge, more than 70 countries have committed to cut cooling emissions while widening access, and India is redirecting around US$1.5 billion of its disaster-mitigation fund towards passive cooling.19 On the health side, the WMO and WHO, with the United States’ NOAA, run the Global Heat Health Information Network, which links scientists, doctors and city officials so that heat-health knowledge is shared rather than rebuilt city by city.20 A South Asia hub is being set up in India with the India Meteorological Department to turn forecasts into early warnings, and the WHO has folded heat into its One Health approach.21 Many of these efforts have gained momentum since the UN Secretary-General’s Call to Action on Extreme Heat in 2024.
The common inference is simple: heat cannot be fought in silos. It belongs to no single department or agency, and the response must be community-led, interagency and anchored by local governments.
What it takes to keep a city cool
If the work must be shared, the question is what should be shared, at what level, and by whom. The science and economics of these cooling strategies are already well understood. The first principle is simple: cool passively before cooling actively. Passive cooling is cheaper and fairer. It also does not fail when the power does.
The base layer is shade and green cover, treated as infrastructure rather than greenwash. This means street trees, shaded bus stops and markets, and parks within walking distance of every housing community. It also includes reflective cool roofs over informal settlements. There, a coat of white paint can lower an indoor temperature by several degrees. Then come cool zones — integrated blue-green infrastructure, suited to local conditions, that anyone can use. Public shelters, libraries and halls should stay open through the hottest hours. Night shelters are needed for those with no access to cooling at home. Clean public drinking water should be available at street corners along the routes that vendors, riders and walkers use most. Rest and water breaks should be written into the rules of schools and worksites, with work shifted away from the worst of the afternoon — extended into the night where needed, within the labour codes and laws.
Alongside this physical infrastructure comes the human: heat-health literacy. People need to know that heatstroke is a medical emergency. They should know that above 40°C a fan can heat rather than cool. An air conditioner set near 27°C with a fan uses far less power. Windows are best opened to the night air and shut against the day. Thirst and urine colour are early warnings of dehydration.22 This basic awareness should be as routine as a fire drill.
Local governments are the nodal point for most of these levers, and the Heat Action Plan is their main tool. A good plan does more than issue warnings or publish data; it should also list potential actions. It should set out concrete measures — cool roofs, shade, water points, adjusted work hours — and assign each to a department with a budget, along with monitoring and public reporting. The bigger step is to fold these measures into the city’s master plan and development plans, so that cooling is built into how the city grows rather than added each summer. Most of that growth is in cities that already exist, so the work cannot wait for green-field land. It must come through retrofitting — greening built-up wards, painting existing roofs, and opening cool spaces in buildings that are already there.
None of this works at a single level. It must run from the individual and the household up through institutions, communities, city departments and government. Each owns a part, and it works only when all of them act together. Heat Action Plans and cool-roof programmes in India and elsewhere have already shown as much.
Shared vision for a cooler future
The man at the bus shelter in London and the family on the Mumbai shore want the same thing: a patch of shade, some moving air, a cool place that does not depend on the power supply or the size of a wallet. What separates them is not the heat but the cooling they can reach. That is the heat divide, and it is the one that must be closed at the earliest.
It will not close on its own. As the planet keeps warming, the heat will keep accumulating, and the divide will widen with it — those who can buy their way to cool will stay cool, and those who cannot will fall further behind. Left alone, that gap has the potential to explode into a public-health and social crisis far larger than the one we see today.
So, the call is plain. Plant the trees, paint the roofs, open the cool rooms, keep the water flowing, and write all of it into how cities are planned and run — making it systemic, not a seasonal response. The next record will come, and it will come soon. The test is whether, by then, the two sides of the divide have moved closer together, or drifted further apart.
Also Read – How IAS Dr. Abhishek Saini is Transforming Child Nutrition Through Community Participation in Meghalaya
