Heatwaves are becoming the norm. This is what Britain will look like in the year 2052 | Bill McGuire

People sleep outside because their houses are too hot to inhabit, water is scarce and supermarkets are for the wealthy

If you think the temperature uncomfortable today, let me take you to the last day of July 2052, the rays of the climbing sun reveal a city still sweltering in the residual heat of the day before. From the air, London resembles a colossal refugee camp. Streets, gardens and parks are teeming with tents and cobbled-together shelters, within which the city’s residents have spent another uncomfortable night away from the heat traps that their houses and flats have become. After six days when the temperature peaked at about 40C, another scorcher is on the way.

Half-hearted attempts to upgrade insulation across the country’s housing stock ran out of steam and cash decades earlier, and most homes still have few barriers to the infiltrating heat. Almost all the country’s electricity is now from renewables, which has brought the cost down, but the relentless onslaught of extreme weather has driven an ever-deepening economic depression across the world. Many now have air conditioning, but can’t afford to run it.