London, long a major population center in the United Kingdom, had suffered from air pollution since at least the 1200s. The fog that regularly blanketed the city was part of its identity. But the morning of December 5, 1952 began with clear skies, though it was quite cold. As usual, coal fires throughout the city, in homes and business, were lit to combat the cold weather. These fires, combined with a weather phenomenon, soon caused the worst air pollution event in the history of Great Britain.
On the previous day, December 4th, a high-pressure system had stalled over London. This caused a temperature inversion that trapped the polluted air of the city below a layer of warm air. There was no breeze to disperse the pollution, and it didn’t take long for the pollutants from the city’s coal fires, factory smokestacks, and diesel engines to create a “pea soup” fog that blanketed all of London by the afternoon of December 5th. The incident later came to be known as the Great Smog of 1952.
The yellow-brown smog made the whole city smell of rotten eggs because it was full of sulfur particles. It was incredibly dense, and people reported not being able to see their feet as they walked. For nearly 5 days flights were grounded and trains could not run. People abandoned their cars in the streets because they could not see to drive them. A black film coated buildings and sidewalks, and anyone brave enough to go outside would find their clothes and skin blackened by soot and grime. The smog even got inside buildings, and move theaters temporarily closed because moviegoers could not see the screen through the smog.
The stagnant pollution also caused severe health problems for the very young, the elderly, and people with pre-existing breathing problems. So many people died from lung ailments from December 5th through the 9th that funeral homes began running out of coffins. East London’s death rate increased nine-fold during the crisis. It is now believed that up to 12,000 people may have died from the Great Smog, either during the event or from lingering health effects afterward.
Finally, on December 9th, winds from the west blew into London, pushing the sulfurous polluted clouds out of the city. Though the government did not do much to help London’s citizens during the Great Smog, there were some in Parliament who felt something needed to be done to prevent such a disaster from occurring again.
In 1956, Parliament passed the Clean Air Act, which restricted coal-burning in cities and gave out grants to help people convert from coal heating systems to cleaner methods. The city of London also began to transition to oil, electricity, and natural gas for heating, though the full conversion took many years, during which time several other less severe smog attacks occurred. But London has never since had a pollution crisis like the Great Smog of 1952.