Cities across Western Europe have been hotter than much of the Middle East this week. The worst European heatwave in history has pushed temperatures as high as 44.3 degrees Celsius in France—its hottest ever day—and broken records in half of Europe’s 850 cities with over 50,000 residents.

Rare red heat alerts have been issued across swathes of France, Britain, Spain and Italy, with the heatwave now moving north and east towards Germany, Poland and the Balkans. More than 50 French departments have registered temperatures above 40℃ (104°F), including Paris. The UK announced its hottest ever June day of 36.9℃, while Spain has reached 42℃ and Italy 41℃.

These maps can be viewed and downloaded as clearer images in PDF format here.

Humidity levels mean the “real feel” is frequently several degrees warmer, leaving tens of millions of people suffering heat in the low 40 degrees in countries utterly unprepared for such temperatures: buildings and cities are not designed to keep cool and only 20 percent of homes have air conditioning. “Tropical nights”, when the temperature does not drop below 20 degrees, or 30 degrees in parts of France, give no relief.

Hundreds of deaths have already been reported. The real toll will not be known for some time but will be in the tens of thousands. Conditions are comparable to the June 2022 heatwave which caused an estimated 70,000 deaths. Another 60,000 were killed in the summer heatwave of 2024. Longer-term negative health impacts will follow the spike in air pollution which accompanies extreme heat. These are disasters on a massive scale.

Most exposed are young children, the elderly, and outdoor workers. Over 1.6 million children in the UK, including 70,000 babies, are living in overheated homes—exceptionally dangerous for children under 5 who are less able to regulate their temperatures. During the 2022 heatwave, deaths in old-age nursing homes increased by over a third.

Among the few heatwave deaths reported in detail during the 2022 and 2024 heatwaves were 51-year-old Montse Aguilar, a Barcelona street cleaner who collapsed with dizziness and pain and hit her head; 50-year-old David Azevedo, a French construction worker who suffered a heart attack; and 54-year-old agricultural worker Dalvir Singh, originally from India, who died in the field where he worked in Italy.

Safiullah, an Afghan gardener in Paris, told France24, “I have no choice. My social circumstances, my professional circumstances, mean I have to keep working, whatever the conditions.” Darren, a bus driver in the UK, told the BBC, “You’ve got the sun beating down, magnified by the glass, and the bus is 20 years old with no air conditioning, it’s unbearable.”

The General Confederation of Labour union in France denounced “barely tolerable” conditions and the Trades Union Congress in Britain reiterated its call for a legal maximum working temperature. But these statements are for the record only. Barring a few agreements with employers about additional breaks, or a cynical call from French teaching unions for members to take strike action on their own initiative, no union in Europe has taken any proactive action to defend its members’ safety.

Every aspect of society is under strain. French medics reported a 20 percent spike in emergency department visits and hospital admissions, reaching “saturation” in Paris. Rates of cardiac arrest have quadrupled, increasing substantially among younger people. UK hospitals are declaring critical incidents as medical machines, cooling and IT systems fail. The scandal of “corridor care” has been made a deathtrap.

Over 1,800 schools are closed in France, with a further 8,000 shortening their hours; roughly 1,000 have done the same in the UK. Train services have been cancelled or disrupted across both countries as the tracks and power lines overheat. Broken or absent air conditioning means many are avoided anyway.

Energy generation is also affected, even as demand from air conditioning and refrigeration units spikes, sending electricity prices soaring. Five UK gas plants reported they were reducing output due to the impact of the weather on their operations. In France, nuclear reactors have been taken offline or had their output reduced as rivers connected to their cooling systems overheated. More than 68,000 homes were left without power in the west of the country after a transformer was damaged.

The cause of the heatwave is an “Omega block”: a horseshoe-shaped band of low pressure around the affected area is dragging in hot air from Africa in the south and trapping it in a “heat dome”. The high pressure also interferes with cloud formation, allowing the sun to beat down.

Climate change increases the severity of these events. According to initial research by France’s Institute Pierre-Simon Laplace, global heating has made the current heatwave 2-4°C worse than would have been the case in the second half of the 20th century. This was confirmed by findings from the World Weather Attribution consortium.

Rising global temperatures are also increasing the frequency of heatwaves on the continent, which is heating twice as fast as the global average increase. Spain, for example, suffered 129 days of heatwave from 1975-2000 and 329 days since the turn of the century. In the UK, the likelihood of 40℃ temperatures has tripled since 2000.

The world is on the threshold of breaching the limit targeted by the 2015 Paris Agreement of 1.5℃ heating above the pre-industrial average. It is projected to reach 2.8℃ by the end of the century based on current policies, which would mean drastically worse conditions than those now seen in Europe. Scientists at the University of Reading recently predicted the UK will see 45℃ (113°F) heat within the next 30 years, overheating 90 percent of homes.

By its nature, the crisis is global. A 2025 Lancet Countdown report revealed that worldwide heat-related deaths had risen 60 percent from an estimated 335,000 a year in 1990-99 to 546,000 annually in 2012–2021.

Earlier this year, a heatwave in India and Pakistan saw temperatures in the high 40 degrees. Official records of deaths are woefully inadequate, but a study released this month from the University of California, Berkeley estimated a day of extreme heat is associated with 3,400 excess deaths—and five consecutive days with 30,000.

The victims are overwhelmingly the most exploited workers, with differences in building density and materials, tree cover and green space, and access to cooling creating a 5.6°C temperature difference between the richest and poorest parts of Mumbai. Economic losses, estimated at $194 billion dollars for the country’s 2024 heatwave, are taken in large part directly out of the wages of India’s 200 million informal workers.

Every day’s delay in ending CO₂ emissions and providing funds to adapt to the warming which has already taken place worsens these outcomes. But the most recent figures show just $2.1 trillion of annual climate finance was made available in 2025, versus the $7.8 trillion needed globally between 2025-2030, according to the Climate Policy Initiative. This rises to $9 trillion in the subsequent five years.

According to the United Nations, an additional $365 billion a year is needed to help developing countries adapt to climate change, of which a pathetic $26 billion is provided.

All initiatives run up against the two fundamental features of an economy run on a capitalist basis: production for private profit, and competition between companies and countries.

Capitalist enterprises are loathe to abandon to their rivals the potential fortunes represented by fossil fuels and their associated industries. According to Oxfam, just six of the world’s largest fossil fuel companies are projected to make profits of $96 billion in 2026—that is $3,000 a second.

The fruits are enjoyed by the world’s richest 10 percent (with an average wealth of PPP$1 million), and particularly the richest 1 percent (average wealth $6 million), whose overall ownership-based emissions—shares etc.—account for 77 percent and 44 percent of total emissions respectively.

Burning fossil fuels to fill the pockets of the rich increasingly means burning human beings to death for profit—another way the capitalist system spitting out wars, pandemics and deaths of despair is toxic to human life.

Society cannot afford the greed of the oligarchy, which must be expropriated. It cannot afford the anarchy of the market, which must be replaced with democratic planning. The only means of accomplishing this is a world socialist revolution carried out by the international working class.