The Year Without a Summer

The Year Without a Summer, also known as the Poverty Year and Eighteen hundred and froze to death, was 1816, in which severe summer climate abnormalities destroyed crops in Northern Europe, the American Northeast and eastern Canada[1][2].

It is now generally thought that the aberrations occurred because of the 5 April–15 April 1815 volcanic eruptions of Mount Tambora on the island of Sumbawa in the Dutch East Indies (in today's Indonesia) which ejected over a million and a half metric tons – or 400 km³[3] – of dust into the upper atmosphere. As is common following a massive volcanic eruption, temperatures fell worldwide owing to less sunlight passing through the atmosphere.

Description

The unusual climate aberrations of 1816 had the greatest effect on the American northeast, the Canadian Maritimes and northern Europe. Typically, the late spring and summer of the northeastern U.S. are relatively stable: temperatures average about 68–77°F (20–25°C), and rarely fall below 41°F (5°C). Summer snow is an extreme rarity, though May flurries sometimes occur.

In May of 1816, however, frost killed off most of the crops that had been planted, and in June two large snowstorms resulted in many human deaths as well. In July and August, lake and river ice were observed as far south as Pennsylvania. Rapid, dramatic temperature swings were common, with temperatures sometimes reverting from normal or above-normal summer temperatures as high as 95°F (35°C) to near-freezing within hours. Even though farmers south of New England did succeed in bringing some crops to maturity, maize (corn) and other grain prices rose dramatically. Oats, for example, rose from 12¢ a bushel the previous year to 92¢ a bushel.

Effects

Many historians cite the year without a summer as a primary motivation for the rapid settlement of what is now the American Midwest. Many New Englanders were wiped out by the year, and tens of thousands struck out for the richer soil and better growing conditions of the Upper Midwest (then the Northwest Territory). (A specific instance of this was when the family of Joseph Smith, eventual founder of the Church of Jesus Christ of Latter-day Saints, moved from Sharon, Vermont to Palmyra, New York in far western New York state after several crop failures.) While crops had been poor for several years, the final blow came in 1815 with the eruption of Tambora.

The eruption of Tambora also caused Hungary to experience brown snow. Italy experienced something similar, with red snow falling throughout the year. The cause of this is believed to have been volcanic ash in the atmosphere.

Europe, still recuperating from the Napoleonic Wars, suffered from food shortages. Food riots broke out in Britain and France and grain warehouses were looted. The violence was worst in landlocked Switzerland, where famine caused the government to declare a national emergency.

Huge storms, abnormal rainfall and floodings of the major rivers of Europe (including the Rhine) are attributed to the event, as was the frost setting in during August 1816.

The lack of food inspired Karl Freiherr von Drais to research new ways of horseless transportation which led to the invention of the velocipede and the Draisine, a forerunner of the modern bicycle.

In July 1816 "incessant rainfall" during that "wet, ungenial summer" forced Mary Shelley, John William Polidori and their friends to stay indoors for much of their Swiss holiday, leading Shelley to write Frankenstein, or The Modern Prometheus and Polidori to write The Vampyre. High levels of ash in the atmosphere led to unusually spectacular sunsets during this period, a feature celebrated in the paintings of J. M. W. Turner. (A similar phenomenon was observed after the 1883 Krakatoa eruption, and on the West Coast of the United States following the 1991 eruption of Mount Pinatubo in the Philippines.)

A BBC documentary using figures compiled in Switzerland estimated that fatality rates in 1816 were twice that of average years, giving an approximate European fatality total of 200,000 deaths.

Causal theories

At the time, no one knew what had caused the aberrant conditions of 1816. One scapegoat was Benjamin Franklin, whose experiments with lightning and electricity were said to have altered the weather. Later, sunspot activity or simple chance were suggested as possible causes.

It was American climatologist William Humphreys who first suggested, in 1920, that the year without a summer may have been caused by volcanic activity. His explanation was inspired in part by a treatise written by none other than Benjamin Franklin. Franklin blamed the unusually cool summer of 1783 on volcanic dust coming from the eruption of Laki in Iceland.

For more details on this topic, see Volcanic winter.