If that excess mortality occurs during a summer week, it is readily linked to the weather. Models take into account age, region, temperature, humidity, long-term mortality trends and known risks to elderly or sick people. Researchers then estimate, or more precisely attribute, how many of those deaths were probably caused by heat. And just like that, additional deaths become heat deaths.

The real danger begins when these figures enter public debate. “More people died than expected” becomes “heat killed them”. “A model estimates” becomes “climate change claims lives”. A statistical approximation becomes a political number.

According to Politico, France reported 2,025 additional deaths during the week from 22 to 28 June, Belgium 1,747 between 18 June and 1 July and Germany 6,800 during the same week as France. The Netherlands recorded a further 480 deaths, while Spain cited 812 heat-related deaths.

When the Numbers Become Political

This is particularly clear in Britain. Imperial College estimated that more than 2,700 people had died from heat in England and Wales across May and June, including 2,200 between 18 and 28 June. At the peak of the June heatwave, the toll was said to have reached 440 deaths a day. More than 40% of those deaths, it claimed, would not have occurred without man-made warming.

Professor Carl Heneghan and Dr Tom Jefferson of the University of Oxford’s Center for Evidence-Based Medicine examined the official figures from the Office for National Statistics more closely. They found no dramatic spike. Mortality during the heatwave remained within the normal range seen in previous years.

Heneghan distilled the issue into one crucial distinction. Models explore what might have happened. Surveillance shows what actually happened. When the two diverge, the data should be scrutinized rather than the model accepted at face value.

That scrutiny is precisely what is missing from alarmist public messaging. The number is large, it comes from a respected institution and it supports the climate narrative. So the media repeat it.

A Model Is Not a Death Certificate

Heat can, of course, aggravate existing illnesses. A heart patient may die during a heatwave because the heat places additional strain on the body. An elderly person may become dehydrated. In care homes, inadequate supervision, a lack of cooling and poorly adjusted medication can prove fatal.

But that is not the same as an accurate count. If someone dies of heart failure on a hot day, the medical cause of death is not automatically “heat”. If more people die than expected during a particular week, they do not automatically become climate deaths. If a model attributes some of those deaths to temperature, it remains an attribution.

Did They Die From Heat or With Heat?

Germany shows how badly this method can misplace responsibility. If elderly patients are left in hospitals without air conditioning while temperatures outside reach 40C, they are not victims of a climate catastrophe. They are victims of political inaction, outdated buildings and failures within the health care system. To count such cases later as heat deaths is to shift the blame.

The inclusion of drowning deaths is even more absurd. The German Life-Saving Association reported at least 99 drownings in Germany in June, the highest figure since the exceptionally hot summer of 2003. The hot weather drew more people to lakes, rivers and public swimming pools. They died by drowning, not from heat.

Yet such distinctions can easily disappear inside statistical models. The Robert Koch Institute estimates heat-related mortality using total deaths by calendar week, state and age group. The calculation does not distinguish between individual causes of death. Someone who drowns during a hot week is therefore counted in the same overall mortality data as a heart patient in an overheated care home.

The method cannot distinguish between such cases with any precision. It takes the excess deaths, overlays temperature curves and calculates a heat-related share. This is where the parallel with Covid becomes obvious.

During the pandemic, Germany argued over whether people had died “from” or “with” Covid. A positive test could be enough for a death to appear in the Covid statistics, even when the actual cause was different. Today, the formula is no longer a positive test but a “hot week”. The thermometer has replaced the PCR test.

Show Us the Deaths

The Oxford researchers are therefore calling for something very simple: better data. Deaths should be published as promptly as possible by the actual date of death and broken down by age, region and cause.

Only then would it be possible to determine whether the claimed heat deaths are borne out by the figures. Anyone claiming thousands of deaths must show them, not merely estimate them.

People die from heart failure, respiratory illness, old age, poor care or a combination of many causes. The statistics recast those deaths as heat deaths. Politicians then recast them as climate deaths. What remains is a number that nobody can substantiate case by case, but that everyone is expected to repeat.