Today in History: Remembering the Great Killer Smog of London

M.C. Millman

Londoners heating their homes and businesses during the frigid winter of 1952 never imagined their burning coal would contribute to the worst air pollution event in the history of the United Kingdom.

Innocent, clear skies over the British capital on the morning of December 5 brought quite the chill along with it. Londoners began their day, as usual, stoking coal fireplaces to warm up. 

The smoke pouring from the coal fireplaces wasn't entirely to blame for the hazy air pollution. According to National Geographic, coal-fired power plants for heat and electricity contributed to the pollution, as did diesel-powered buses for public transportation. These factors, combined with the weather, all contributed to the Great Smog of London.

Typically, smoke and other air pollutants disperse into the atmosphere. However, at this point, an anticyclone was hanging over London. This high-pressure weather system caused an inversion, trapping the cold air at ground level. According to the Met Office, the anticyclone ultimately trapped the particles and gases from factory chimneys and the pollution driven by winds from other industrial areas on the continent. 

The pollutants caused the fog to take on a yellow hue, known as a "pea-souper". Aside from underground transportation, all travel and shipping came to a standstill because visibility was severely limited. According to Britannica, many people abandoned their cars on the road, and pedestrians could barely see even their feet when walking. Indoor concerts and plays had to be canceled because it was so difficult to see the stage even indoors. Press reports claimed that cattle were asphyxiated by the smog. 

The fog took five days to clear, but not without devastating the area. The Registrar General published that about 4,000 died from the smog. Still, according to Britannica, the estimate is closer to 12,000 when accounting for the long-lasting effects of the smog. The fog caused long-term breathing problems in many people.

After the smoke cleared, there was a dire need to limit the amount of air pollution. It took four years, but several laws were enacted, including the Clean Air Acts of 1956 and 1968. These acts established smoke-free areas around the city, required urban residents and factories to convert to smokeless fuels, and banned the emissions of black smoke. 

Homeowners were given grants for switching to different heating sources, like natural gas, oil, and electricity. 

Although there was another smog crisis in 1962, it wasn't of the same magnitude. According to Britannica, the Clean Air Act helped improve public health in Britain and is generally considered a significant event in the history of environmentalism.

Photo Criedt: Flickr