Great Smog of London
1952 CE.
Shown on the map at 51.517°, 0.117°.
The Great Smog was a severe air pollution event that affected London, England, in December 1952. A period of unusually cold weather, combined with an anticyclone and windless conditions, collected airborne pollutants—mostly arising from the use of coal—to form a thick layer of smog over the city. It lasted from Friday, 5 December, to Tuesday, 9 December 1952, then dispersed quickly when the weather changed. The smog caused major disruption by reducing visibility and even penetrating indoor areas, far more severely than previous smog events, called "pea-soupers". Government medical reports in the weeks following the event estimated that up to 4,000 people had died as a direct result of the smog and 100,000 more were made ill by the smog's effects on the human respiratory tract. More recent research suggests that the total number of fatalities was considerably greater, with estimates of between 10,000 and 12,000 deaths. London's poor air quality had been a problem since at least the 13th century. The diarist John Evelyn had written about "the inconveniencie of the aer and smoak of London [sic]" in Fumifugium, the first book written about air pollution, in 1661.
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