A historic heatwave is rolling east across Europe – after more than a week baking France, Belgium and the Netherlands, it is now reaching Germany, Poland and the Czech Republic.It has all become wearily familiar. This is my fifth year working as a journalist in France, and I’ve covered a major heatwave in all but one of them.Each year the peak climbs higher – 39 degrees Celsius (102 degrees Fahrenheit), even 40 – numbers once unthinkable in Paris, a city where, unlike in China or the United States, air conditioners (AC) remain a household rarity.With every heatwave, the same scene plays out across Paris and the rest of France: people scrambling for a fan, an air conditioner, anything that might cool a room enough to let them sleep.For years I reported on that frenzy as the calm one, watching from the comfort of an air-conditioned office. This year, I became one of them. A new job had turned my flat into my office – which, naturally, had no AC.The challenge was getting my hands on one. As in previous years, people rushed to buy as soon as the heatwave was announced. When I went to my local Darty – one of France’s big electronics and appliance chains – on June 19, I found only an empty shelf. Same story at a second branch.