How an Extreme Combination of Fog and Air Pollution Brought London to a Standstill and Resulted in Thousands of Fatalities

At first, the headlines were calm. “Fog blanketed London all today,” the Evening Standard reported dispassionately on Friday, December 5, 1952. “London’s fog grew worse in places this evening.”

Londoners, after all, were used to dense fogs, sometimes so thick that they called them “pea-soupers.”

But this fog was unprecedented. By the second day, it had “reduced visibility in some places almost to nil,” the Daily Telegraph wrote. Car traffic slowed to a “walking pace,” thugs emerged from the fog to steal women’s handbags, and a disoriented mallard flew into a pedestrian.

When the Great Smog of 1952 finally lifted on December 9, 4,000 people were dead from the effects of the extreme pollution, according to government reports. Retrospective assessments estimate that the number of fatalities could be almost triple that.

The extreme darkness and lethality of the Great Smog would haunt Londoners for years, delivering both lingering health effects and legislation that would transform air pollution for decades to come.

What it was like during London's Great Smog of 1952 - archive video

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T.S. Eliot wrote about “the yellow fog that rubs its back upon the window-panes,” the witches in Macbeth spoke of “the fog and filthy air,” and a British man even coined the term “smog” in 1905 to describe the atmospheric mixing of smoke and fog over the British Isles. But in the years before 1952, pea-soupers had become rarer in London, largely due to urban air quality improvements as factories moved out of the city in the wake of World War II.

As the winter of 1952 set in, though, the government sold low-smoke, black anthracite coal abroad to finance its war debts. As a result, Londoners had to burn cheaper, lower-quality coal, colloquially known as “nutty slack.”

“It took enormous amounts of nutty slack to heat the average home,” Kate Winkler Dawson wrote in Death in the Air. “The cheaper brown coal was inefficient and much dirtier to burn, which created more smoke and more pollution.”

Then came the perfect storm. On December 5, as cold weather in London prompted residents to burn more cheap coal, a high-pressure wind system known as an anticyclone settled over the city, trapping cold air beneath warm air. Pollution from coal fires, diesel buses and factories could not travel up to the atmosphere, instead hovering in a deadly, stagnant smog.

“It’s like you were blind,” Stan Cribb, a mortician who lived through the Great Smog, told NPR.

Bus routes stopped running, and drivers abandoned their cars on the streets in the thousands. Accidents strained ambulances, which took five or six times as long to get to hospitals.

Finally, after five days, the fog lifted. Initial reports of the death toll put the number around 160.

The science of smog - Kim Preshoff

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But in the coming weeks, scrutiny of the initial estimates arose. Florists ran out of flowers, and undertakers ran out of coffins, signaling extreme mortality rates.

Public health officials, politicians and activists began to investigate the causes and effects of the smog to prevent another deadly episode. Speaking to the House of Commons in May 1953, Norman Dodds, a member of Parliament from Dartford, Kent, said he was “amazed at the number of people whom I met who were suffering from chest trouble from which they did not suffer before the fogs of last winter.”

Dodds suggested that 6,000 more people died in Greater London in December 1952 than December 1951, a shocking increase he attributed to poor air quality. A similar smog four years earlier in Donora, Pennsylvania, reportedly killed only 20 people. “America usually does things in a bigger way than we do,” Dodds said, “but I wonder what they are thinking about 6,000 English people dying in Greater London alone.”

While the government’s response was sluggish at first, the Clean Air Act of 1956, passed in response to the Great Smog, heavily regulated the burning of coal and established smoke-free urban areas throughout England.

It was a major piece of environmental legislation. “The act was truly revolutionary, representing a major global milestone in environmental protection,” correspondent Jon Excell later wrote for the BBC. “In the years that followed, a host of other industrial nations were inspired to follow suit.”

Out of the smoke and soot that once blanketed London, new conceptions of public health and environmentalism emerged. The Great Smog of 1952 was, thankfully, the last of its kind in Britain to date.

Eli Wizevich | | READ MORE

Eli Wizevich is a history correspondent for Smithsonian. He studied history at the University of Chicago and previously wrote for the El Paso Times.