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.
