THE GREAT LONDON SMOG
OF 1952

The Great Smog of '52 or "Big Smoke" was a severe air-pollution event that affected London during December 1952. A thick layer of smog hung over the city from Friday, December 5th to Tuesday, December 9th, 1952, and then dispersed quickly after a change of weather. An estimated 12,000 people died due to this event alone.

Although it caused major disruption due to the effect on visibility, and even penetrated indoor areas, it was not thought to be a significant event at the time, with London having experienced many smog events in the past, so-called "pea soupers". Government medical reports in the following weeks estimated that up until 8 December 4,000 people had died prematurely and 100,000 more were made ill because of the smog's effects on the human respiratory tract. More recent research suggests that the total number of fatalities was considerably greater, at about 12,000.

It is known to be the worst air-pollution disaster in the history of the United Kingdom.

CAUSES

Coal Usage

Vehicle Exhaust

Weather

Post-war domestic coal tended to be of a relatively low-grade, sulfurous variety which increased the amount of sulfur dioxide in the smoke. There were also numerous coal-fired power stations in the Greater London area, all of which added to the pollution.

Additionally, there were pollution and smoke from vehicle exhaust (particularly from diesel-fuelled buses, which had replaced the recently abandoned electric tram system) and from other industrial and commercial sources.

On December 4th, 1952, an anticyclone settled over a windless London, causing a temperature inversion with cold, stagnant air trapped under a layer of warm air. The resultant fog, mixed with chimney smoke, particulates such as those from vehicle exhausts, and other pollutants such as sulfur dioxide, formed a persistent smog, which blanketed the capital the following day. The presence of tarry particles of soot gave the smog its yellow-black colour, hence the nickname "peasouper". The absence of significant wind prevented its dispersal and allowed an unprecedented accumulation of pollutants.

IMPACT

There was no panic, as London was renowned for its fog. In the weeks that ensued, however, statistics compiled by medical services found that the fog had killed 4,000 people. Most of the victims were very young or elderly, or had pre-existing respiratory problems. Most of the deaths were caused by respiratory tract infections from hypoxia and as a result of mechanical obstruction of the air passages by pus arising from lung infections caused by the smog. The lung infections were mainly bronchopneumonia or acute purulent bronchitis superimposed upon chronic bronchitis. More recent research suggests that the number of fatalities was considerably greater, at about 12,000.

Even today, MILLIONS OF PEOPLE around the world die as a result of air pollution.

In just 2012, the World Health Organization estimated 7 million pre-mature deaths (1/8 of global deaths) were related to air pollution.

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