Coal Emissions Found in the Mysterious, Deadly 1952 London ‘Killer Fog’

Another killer mystery in London has been solved.

The mystery of the Great Smog of London in 1952, which lead to over 12,000 people dying, has been solved. As a result, a better understanding of air chemistry could be used to fight the air pollution crisis in China, and it could lend insight to the U.S.’s climate change debate.

In December 1952, London was visited by a dense fog for five days which left 150,000 hospitalized. Over 12,000 people — and thousands of animals — perished from the fog.

This event – regarded as the worst air pollution event in European history – has been solved by an international team of scientists from China, the U.S. and the U.K. They recreated the deadly fog in a laboratory with atmospheric measurements from the insanely polluted cities of Beijing and Xi’an.

According to the results, Renyi Zhang, atmospheric scientist from Texas A&M University and lead author of the study, said the fog contained sulfate and sulfuric acid particles facilitated by nitrogen dioxide that evaporated. And while sulfate is formed only with ammonia in play, the particles were formed from burning coal, as was the nitrogen dioxide component.

Fortunately, in China, the haze isn’t as dangerous. Ammonia mainly comes from fertilizer and automobile use. Although the country receives sulfuric dioxide and nitrogen dioxide emissions from power plants, the haze is chemically comprised of smaller particles and is neutral – not acidic – without the ammonia largely in play.

Zhang advises on Live Science, “Reduction in emissions for nitrogen oxides and ammonia is likely effective in disrupting this sulfate-formation process.”

With this new information, China has a better idea to improve their air quality and perhaps the U.S. will see this hard evidence as further reasoning to care about protection from climate change.