Volcanoes are nothing unusual on Iceland, but the eruption that started 230 years ago on June 8, 1783 was one of the deadliest events we remember. Over a six-month period an estimated 14 cubic kilometres of lava poured out from a total of 135 fissures near the old crater ofLaki, covering an estimated 2,500 square kilometre of land.
One of the eyewitnesses – the shepherd Jón Steingrímsson – described the unfolding disaster:
“First the ground swelled up with tremendous howling, then suddenly a cry shattered it into pieces and exposing [the Earth´s] guts, like an animal tearing apart its prey. From the smallest holes flames and fire erupted. Great blocks of rocks and pieces of grass were thrown high into the air and in indescribable heights, from time to time strong thunders, flashes, fountains of sand , lightening [?] and dense smoke occurred… Earth trembled incessantly. … how terrible it was to see, such signs of an angry god… [now] it was time to confess to the lord.”
More than 9.000 people were killed by the direct effects of the eruption, like lava and poisonous gases. The ash was carried away with the wind and poisoned the land and the sea, killing half of the Icelandic cattle population and a quarter of the sheep and horses population. Nothing would grow on the fields and no more fish could be found in the sea. In the resulting famine (1783-1784) estimated twenty thousand people died – almost a third of Iceland’s population at the time.
Gilbert White (1720-1783), in his classic The Natural History and Antiquities of Selborne (page 310), described that summer as “an amazing and portentous one, and full of horrible phenomena; for, besides the alarming meteors and tremendous thunder-storms that affrighted and distressed the different counties of this kingdom, the peculiar haze, or smokey fog, that prevailed for many weeks in this island, and in every part of Europe, and even beyond its limits, was a most extraordinary appearance, unlike anything known within the memory of man.
“The sun, at noon, looked as blank as a clouded moon, and shed a rust-coloured ferruginous light on the ground … but was particularly lurid and blood-coloured at rising and setting.
“The country people began to look with a superstitious awe, at the red, louring aspect of the sun; and indeed there was a reason for the most enlightened person to be apprehensive; for, all the while, Calabria and part of the isle of Sicily were torn and convulsed with earthquakes; and about that juncture a volcano sprang out of the sea on the coast of Norway.”
But the Laki eruption had even more widespread effects. In the years after the eruption the climate in Europe deteriorated, characterized by cool and rainy summers. The resulting crop failures triggered one of the most famous insurrections of starving people in history – the French Revolution of 1789.
 Lakagígar is a row of craters approximately 25 km long; Laki stands near the centre.
This article is thanks to David Bressan, a freelance geologist interested in the history and the development of geological concepts through time.