London’s killer smog
For some 300 years, coal-burning in London transformed the city's frequent fogs into sickening smogs. The Victorian taste for dark wallpaper was in part a clever way to disguise soot, and Dickens wrote of snowflake-sized soot particles. Still, nobody anticipated the disaster of December 4-8,1952, when a smog of epic proportions settled in beneath a stagnant dome of high pressure. By Friday, the smog's second day, it was hard to see across the street through the yellowish muck, and within the next two days the visibility had dropped to as low as 0.3m/1ft. Since this wasn't precisely a weather disaster, there were no warnings per se on radio or TV; many Londoners made things worse by going home and stoking up their stoves. London's daily fatality rate jumped from the usual 300 to nearly 1000, mostly due to respiratory failures. In total the unnamed onslaught either caused or hastened some 4000 deaths.
A similar smog attack in Donora, Pennsylvania, four years earlier had killed 20 people and sickened hundreds. London cleaned up its act in a hurry with bans on black smoke and a shift toward smokeless fuels; the last major London smog was in 1962. The city's present-day air isn't exactly pristine, but central London now gets as much as 50 percent more winter sunshine than it did when coal was king.