Weather Extremes in Modern Times

Abstract

In 1816, Against A foreboding climatic background, Mary Shelley wrote Frankenstein. She might well have begun: “It was a dark and stormy decade …” During the previous year, much of the world had been shrouded by the great ashen veil cast across the skies by the massive Tambora volcanic eruption in April 1815. Europe’s 1815– 1816 was a cold, gloomy, and tumultuous time. Crops failed and tem­peratures fell. Bonaparte was consigned to the rocky island of St. Helena, Beethoven entered his more radical and introspective late period, and minor autocratic monarchies around the continent came under increasing political siege as democratic impulses stirred. This chapter examines some of the shorter- term climate shifts and extreme weather events that have occurred over the last two centuries. The disrupted weather following the Tambora eruption, for example, shows how small changes in temperature and rainfall can have major consequences, including failed harvests and epidemic outbreaks. In mid- nineteenth- century Ireland, the failure of the potato crop in wet and relatively warm conditions contributed to food insecurity that devastated the local population. Unusual weather extremes in late- nineteenth- century China, including a period of cooling, facilitated the Third Pandemic of bubonic plague, which spread rapidly through populations already under stress due to harvest failures, conflict, and political turmoil. Such events may intensify in the coming decades as the Earth’s average temperature rises and climatic cycles are disrupted and become more variable. Additionally, the consequences for human population health are amplified by social and political mismanagement and turmoil. We can expect climate change to act as a “force multiplier,” exacerbating many of the world’s health problems. From the mid- nineteenth century, the northern hemisphere’s Little Ice Age receded as solar activity regained its twelfth- century peak level. The depths of the cold had been reached around 1700 C.E., and the cool­ing influence of the Siberian High was now receding. The almost year- round ice and snow in northern Europe during those super- chilled earlier times were long gone, and the snowbound, though increasingly grimy, White Christmases of early- 1800s Dickensian London were waning.