High Wind Watch

Iceland Volcanos, Climate Change and Benjamin Franklin

April 23, 2010, 7:22:44 AM EDT

Iceland volcanic eruptions, namely a vast outpouring of lava in 1783 to 1784, have been credited with sparking the earliest theories on volcanic climate change.


Image Credit: Wikipedia

The Laki eruption, a "fissure" eruption that unleashed a "flood basalt," poured forth an estimated 14 cubic kilometers, or 3.4 cubic miles, of fluid basalt lava. The Laki eruption was related to the Grimsvotn Volcano.

Released along with the sea of lava were vast clouds of sulfur dioxide and highly poisonous hydrofluoric acid. Estimates of gas emitted are for 120 million tons of sulfur dioxide and 8 million tons of hydrogen fluoride.

Coincident with, and following, the great Laki lava flows were abnormal patterns of weather in Europe.

During the exceptionally hot summer of 1783, sulfuric haze fanned out over northern Europe, leading to elevated death rates, but the following winter turned harshly cold with long stretches of frost in England.

Observers in Europe made note of the dullness of the sun and daylight, as well as the reddish sunrises and sunsets.

Elsewhere, the winter of 1783-84 was also severe in the nascent United States. The Asian Summer Monsoon was weakened. Effects, including famines, in far-flung areas from the African Sahel to Japan, have been attributed to climate effects from Laki.

The bitter cold of the United States winter of 1783-84 was apparently well-known to Benjamin Franklin. He is on record as having spoken of the widespread haze, or "fog," the weakened sunlight and the hard winter, which set in early and had long-lasting snow cover. He was also apparently aware of the Iceland eruption, with its widespread smoke, and the possibility that it played a part in the effects observed.

Some are wondering if Eyjafjal, the latest Iceland volcano to erupt, could have significant impact upon weather and climate. It would seem that, thus far, its eruption has been modest, at least with an eye to any substantial climate effect. An eruption of Eyjafjal's much bigger nearby sister, Katla, could be another story, as the dangerous Katla has shown a history of powerful, voluminous eruptions of both ash and basalt lava.

Report a Typo


Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.

More Weather News