For a brief moment in the middle of last month, London was hotter than Cairo. Temperatures reached 40C, the hottest this country has ever seen. Ice creams melted. Train tracks expanded. The nation wilted.
These temperatures would have come as no great shock to the experts. Heatwaves like July’s will become increasingly common, and it will be cities that suffer the most; because of the “urban heat island” effect, they are often up to 10 degrees hotter than rural areas.
