On the 5th of December, 1952, an unusually heavy fog descended on London in the UK. It remained
in place for five days, bringing the capital to a standstill... and yet it caused no panic.
Fog was a common phenomenon within London and, as dramatic as this fog was, it was thought
of as just another example of typically British weather. It wouldn't be until much later that the
true cost of the great smog of 1952 was realized. London is an incredibly densely populated city.
With so many people and so much industry concentrated in one place
it has always suffered from poorer air quality than other cities in the UK.
Even in Victorian times the city was infamous for its foggy streets. Writers at the time referred
to these fogs as "pea soupers" - an allusion to the colour and density of the fog being similar
to that of soup. There was some improvement in London's air quality as the city entered the
1900s, but by 1952 pollution was still very much a problem. At that time coal was still a common
power source with numerous coal burning power plants situated within the boundaries of London.
Coal was also an important domestic fuel: Londoners had been burning a great deal of it
to heat their homes during the particularly cold winter of 1952. With the Second World War having
concluded less than a decade ago resources were still a little thin on the ground. Most people,
therefore, were reduced to burning low quality coal which didn't combust very cleanly.
The sum of all these factors was that London produced a huge amount of air pollution.
Weather conditions on the 5th of December, 1952, conspired to trap this pollution within the city,
a complete lack of wind combined with a zone of high atmospheric pressure effectively
pushing the warm air rising from chimneys and smokestacks straight back down to street level.
The byproducts of domestic fireplaces and factories all over the city
quickly formed a foggy blanket thick enough to cover all but the tallest of buildings.
The fog was severe on the first day, and it got worse with each day that passed,
with factories continuing to belch pollution into the atmosphere at an astonishing rate. A million
kilograms (or 1,000 metric tonnes) of smoke and two million kilograms or (2,000 metric tonnes)
of carbon dioxide, for example, were released each and every day, swamping the city. Londoners
were used to fog, but this was on another level. This fog was extremely thick and dense,
restricting visibility to just a few strides. In some places it had a yellowish or greenish hue,
and many reported that it stank of rotten eggs - something which led people to don masks or other
face coverings whenever they had to venture outside. Despite the noxious appearance of the
fog, few people were worried about air quality. Visibility was a much more pressing issue. The
city's transport networks seized up. Barely any planes could take off or land, and the
vast majority of flights were diverted to other airports. Buses and other forms of above-ground
public transit were cancelled, as drivers simply couldn't see far enough to safely complete their
routes. This left the London Underground as the only available means of public transport
for millions of Londoners. Private transport was equally affected. Roads became blocked by multiple
accidents, and even those roads that were still moving were doing so with agonizing slowness.
While the fog caused travel chaos, it also represented an opportunity for thieves.
With almost zero visibility and police unable to get around, crime skyrocketed. There were
hundreds of reports of robberies and muggings, with the thieves getting away under cover of the
fog. In addition to this wave of opportunistic crime most ordinary activities came to a halt:
sporting fixtures were called off when it became apparent that the spectators could not
see the players, the players could not see one another, and nobody at all could see the ball.
Workers were sent home from their offices or could not make it into work in the first place.
Schools were closed and even theater performances were affected: several were cancelled when fog
seeped in through windows and doors and filled the auditorium. Personal accounts from those
who were alive at the time gave some idea of what it must have been like to navigate
London during the smog. People recall feeling their way along hedges on their way to school
and holding hands with their friends so as not to become separated. Elsewhere commuters were
escorted through the streets by policemen bearing torches, or else used the light glinting off
overhead electric trolley lines to find their way. When (or if) people arrived at their destinations
many found their clothes blackened with soot, and couldn't stop coughing for days.
Some people reported taking lamps out into the street and still seeing nothing. Around the
Isle of Dogs many people noted that the fog was too thick for them to even see their own feet.
Doctors found themselves in high demand... but at the same time struggled to complete house calls
because of the fog. Given that the Underground was the only remaining viable way to get around
queues for tickets stretched into the thousands. For five days London endured the Great Smog...
and then, as the weather changed, the fog cleared away. The city - which had been trapped in a
perpetual twilight for five long days - started moving again. Roads cleared, bus services resumed,
and Londoners returned to work after one of the strangest weekends that many had ever experienced.
It took some time before the real impact of the fog was known. Respiratory illness
is a quiet killer, and in this case those it killed were mostly the sick or the elderly.
Doctors in hospitals across the capital noted that they'd experienced an unusually
high level of mortality during the fog and doubtless made an association between the two.
The average Londoner, however, had no reason to think that the
smog was anything other than just some very severe inclement weather.
Months would pass before the wave of deaths and respiratory illnesses was noticed...
and even once it had been noticed the impact was extremely difficult to gauge. Many of those who
were affected didn't pass away during the fog, but instead had their lives massively
shortened. Someone who died prematurely from respiratory illness a year after the Great Smog,
for example, might not have been counted as part of the death toll. Even so the most conservative
estimates as to the number of deaths state that at least 4,000 people were killed by the smog.
The smog and the chaos it caused were a wake up call for many. Hundreds of those who endured it
noted that the experience changed their attitude towards the environment. It certainly moved air
quality up the political agenda, and in 1956 the Clean Air Act was introduced.
This legislation made mandatory the use of smokeless fuels in built up areas, and also
limited the amount of air pollution factories were allowed to disperse into the atmosphere.
While the act itself has been updated and replaced several times over the years many
of its principles have remained in place to this day. As a consequence the air quality in London
has significantly improved. The most visible and odorous pollutants have been cracked down
on particularly hard, leaving the city looking and smelling far better than it might have done
70 years ago. It is unlikely that there will ever be another incident like the Great Smog of 1952.
However, the problem of air pollution in the city has not been resolved. By some estimates almost
4,000 londoners die prematurely each year as a result of air pollution.
That's the same number as were killed by the Great Smog. In contrast to the Great Smog,
though, these deaths occur year on year and are considered largely unremarkable. The Great Smog of
London was dramatic and terrifying for those who endured it, but the dramatic nature of it was what
opened the door to such decisive and meaningful change in the aftermath. Politicians and lawmakers
couldn't ignore the issue of air pollution when they could both see and smell it in their streets.
Given that another smog is unlikely to hit the city today the issue of air pollution
is one which still looms large but which, at the same time, has become very easy to ignore.