London Fog

The infamous pea soup fog of London dates back as far as the thirteenth century when the budding metropolis was prompted to enact the first environmental legislation targeted at reducing air pollution from coal smoke. Over the ensuing centuries, the dense combination of smoke and fog- later termed smog- only grew worse. By the eighteenth century, coal was the primary source of heat in every home and business in the city.

The Industrial Revolution quickly ushered in a burgeoning crisis. As more and more factories turned to coal-power, air pollution sky-rocketed in the late eighteenth and nineteenth centuries. Water vapor mingled with coal fire particulate created a dense atmospheric layer that hung low in the city as pressure systems kept the air stagnant. The thick smog would regularly reduce visibility for days at a time until changing wind patterns could clear the city. Fog-related deaths were not uncommon and long-term exposure to smog-laden air led to chronic lung illnesses.

It wasn’t until the Great Smog of London in December of 1952 that Parliament finally made significant changes to improve air quality. The dense smoke was trapped in a low pressure weather system for days on end and was so thick, pedestrians were unable to see their feet. Traffic was severely disrupted, livestock suffocated, and even indoor activities were hampered by reduced visibility as the smog permeated dwellings and commercial establishments.

The impact to commerce combined with the high death toll led Parliament to enact the Clean Air Act four years later. The monumental legislation was a major milestone in environmental reform and contributed to the improved air quality in modern day London.