PosterPDF Available

Impacts of the Laki Fissure Eruption of 1783 on North America.

  • German Maritime Museum - Leibniz Institute for Maritime History


I prepared this poster for the third VICS (PAGES Volcanic Impacts on Climate and Society) meeting in Tucson, Arizona. It describes the geology of Iceland, the consequences of the 1783 Laki fissure eruption (Lakagígar) on the northern hemisphere as well as the extraordinary phenomena that could be observed in Europe following the eruption. The poster also explores what consequences the eruption had on North America, mainly exceptionally cold winters that set many records. The poster concludes with open research questions for future archival research in American and Canadian archives.
From 8 June 1783 to 7 February 1784 the Laki fissure (Lakagígar) in Iceland‘s remote
highlands erupted. It released large amounts of gases (including 122 megatons of sulfur
dioxide) and produced the largest amount of lava (14.7 km3) of any eruption in the last
millennium, which together formed a dry and sulfuric fog. !
The Laki fissure is 27 km long and consists of 140 craters. Iceland is one of most active
volcanic zones, due to its location on top of the Mid-Atlantic Ridge and above a hotspot.!
The consequences for Iceland were catastrophic: The eruption caused a famine, which killed
almost a fifth of the population. The world outside Iceland did not know about the eruption.!
1. Introduction
Fig. 8. Occurrence of the Laki
haze. (Map by Thordarson / Self
2003, fair use.)!
Fig. 7. Satellite image from 11 May 2010, the ash plume caused by
Eyjafjallajökull is carried towards Europe. Perhaps it looked similar in 1783.
(Image by NASA Goddard/MODIS Rapid Response Team, public domain.) !
Fig. 6. Painting of the flooding of the
River Main in Würzburg, southern
Germany, in February 1784. It was the
second highest flooding event there
since 1342. (In the public domain.)!
Fig. 5. Print of the “Great Meteor,“
which appeared on 18 August 1783.
(Print by Henry Robinson, Online
Collection, the British Museum, CC
BY-NC-SA 4.0.)!
Fig. 4. Illustration of the 5 February
1783 earthquake in Calabria and Sicily
(7.0 magnitude, XI Mercalli scale). The
print shows the destruction caused by
the earthquake. (In the public domain.) !
Supported by
Katrin Kleemann is a doctoral candidate at the Rachel Carson Center for
Environment and Society / LMU Munich in Germany, where she studies
environmental history and geology. Katrin is the recipient of a fellowship of the
Andrea von Braun Foundation. This poster presentation has generously been
supported by a travel grant from VICS and from the Amerika-Institut at LMU.!
Background image!
The photo shows a lava field produced by
the Laki fissure eruption in 1783. Today it
is covered by moss. (The image was taken
by Katrin Kleemann in August 2016.) !
Contact me via
About the Author
Impacts of the Laki Fissure Eruption of
1783 on North America
Katrin Kleemann, M.A.
Rachel Carson Center, LMU Munich, Germany
In the summer of 1783 the contemporaries in Europe gazed at the sky and observed an
unusual dry fog with a sulfuric odor that lasted for up to three months. Several extraordinary
phenomena characterized 1783: !
an unusual heat!
crop damage by sulfuric acid; sticky “honey dew” on some plants!
a greater than usual number of thunderstorms !
earthquakes and a tsunami in Italy!
a newly emerging island off the coast of Iceland!
a meteor passing over England and France!
an exceptionally cold winter!
ice drifts and flooding of central European rivers!
What had caused these bizarre occurrences? At the time, contemporaries were left alone to
contemplate these unusual events. It took one hundred years for the contemporaries to
connect the dots between the Laki fissure eruption and the dry fog, and importantly separate
some of those phenomena that were unrelated. !
Did you know? The ratification of the Treaty of Paris was delayed by the cold
winter that followed the eruption as the passage of ships, and therefore communication, was
hindered by ice and storms. The winters from 1783 to 1786 were not only severe in Europe,
in the eastern United States the winters were colder than average as well.!
NW Alaska saw an extremely cold summer in 1783 (4°C below mean); oral Inuit
history remembers “the time summer time did not come;” with a significant
decrease in the local Inuit population (Jacoby 1999)!
1783-1784 was one of the longest winters in the eastern US; with snow in late April!
this winter also saw the greatest snowfall ever in New Jersey!
records show the longest period of below 0°C temperatures in New England and the
longest freezing over of Chesapeake Bay during this winter!
Charleston Harbor froze over in February 1784, and ice skating was possible!
the Mississippi River at New Orleans froze over (13-19 February 1784) and ice floes
appeared in Gulf of Mexico, 100 km south of New Orleans (all Ludlum 1966)!
It is unclear whether the dry fog was observable from North America; Hudson Bay records
and weather diaries from the US do not mention unusual skies in 1783. (Stothers 1996)!
The summer in North Alaska and the winters in the eastern United States were colder than
average. It remains to be answered whether the cold winters in Europe and North America
were in fact caused by the Laki fissure eruption. !
Several questions remain open at this point and need further investigation using North
American contemporary sources, such as:!
How, if at all, did contemporaries in North America react to the news about the
extraordinary phenomena in Europe?!
Was the discourse in North America influenced by the European one, for instance
did Americans fear living in a time of a subsurface revolution too?!
Did the dry fog also cause excess mortality in North America?!
Did sulfuric acid damage plants in North America?!
Did sunsets and sunrises also appear blood red in North America?!
D’Arrigo, Rosanne, et al. “The Anomalous Winter of 1783-1784: Was the Laki Eruption or an Analog of
the 2009-2010 Winter to Blame?” Geophysical Research Letters 38 (2011).!
Jacoby, Gordon C., et al. “Laki Eruption of 1783, Tree Rings, and Disaster for Northwest Alaska Inuit.”
Quarternary Science Reviews 18 (1999):1365-1371. !
Kleemann, Katrin. “Speculating About the Weather: The Unusual Dry Fog of 1783.“ NiCHE, 2 Oct 2017. !
Kleemann, Katrin. “Volcanoes, Climate Change, and Society: History and Future Prospects.“ Blog, 23 November 2017. !
Ludlum, David M. Early American Winters, 1604-1820. Boston: American Meteorological Society, 1966.!
Scarth, Alwyn. Vulcans Fury: Man Against Volcano. Hong Kong: World Print Ltd, 1999. !
Schmidt, Anja, et al. “Climatic Impact of the Long-Lasting 1783 Laki Eruption: Inapplicability of Mass-
Independent Sulfur Isotopic Composition Measurements.” Journal of Geophysical Research 117 (2012).!
Stothers, Richard B. “The Great Dry Fog of 1783.” Climatic Change 32 (1996):79-89.!
Thordarson, Thorvaldur, and Stephen Self. Atmospheric and Environmental Effects of the 1783-1784
Laki Eruption: A Review and Reassessment.” Journal of Geophysical Research 108 (2003). !
Fig. 3. A map of Iceland‘s geology. (This map was created by Katrin Kleemann and is built upon
materials from Gingko Maps, CC BY 3.0 license.) !
3. Impacts on North America
4. Conclusions and Future Work
2. Consequences for Europe
Further Reading
Fig. 1 - 2. View of the Laki fissure from Mount Laki. Fig. 1 shows the SW and Fig. 2 shows the NE part, with the
Vatnajökull ice shield in the background. (Photos taken by Katrin Kleemann.) !
ResearchGate has not been able to resolve any citations for this publication.
Full-text available
The multi-stage eruption of the Icelandic volcano Laki beginning in June, 1783 is speculated to have caused unusual dry fog and heat in western Europe and cold in North America during the 1783 summer, and record cold and snow the subsequent winter across the circum-North Atlantic. Despite the many indisputable impacts of the Laki eruption, however, its effect on climate, particularly during the 1783–1784 winter, may be the most poorly constrained. Here we test an alternative explanation for the unusual conditions during this time: that they were caused primarily by a combined negative phase of the North Atlantic Oscillation (NAO) and an El Niño-Southern Oscillation (ENSO) warm event. A similar combination of NAO-ENSO phases was identified as the cause of record cold and snowy conditions during the 2009–2010 winter in Europe and eastern North America. 600-year tree-ring reconstructions of NAO and ENSO indices reveal values in the 1783–1784 winter second only to their combined severity in 2009–2010. Data sources and model simulations support our hypothesis that a combined, negative NAO-ENSO warm phase was the dominant cause of the anomalous winter of 1783–1784, and that these events likely resulted from natural variability unconnected to Laki.
Full-text available
The long-lasting 1783-1784 CE Laki flood lava eruption in Iceland released around 120 Tg of sulfur dioxide into the upper troposphere/lower stratosphere. Northern Hemisphere temperature proxy records of the 1780s indicate below-average temperatures for up to three years following the eruption. The very warm summer of 1783 in Europe, which was followed by a very cold winter, may have been caused by the eruption, but the mechanisms are not yet well understood. Some studies attributed the cold winter 1783-1784 to natural variability of climate. However, our climate model simulations show that the Laki radiative effects lasted long enough to contribute to the winter cooling. We suggest that sulfur isotopic composition measurements obtained using samples from Greenland ice cores do not provide evidence of either a short-lived volcanic aerosol cloud or a short-lived climatic impact of the Laki eruption. In fact, the applicability of mass-independent sulfur isotopic composition measurements for interpreting the climatic impact of any high-latitude eruption remains yet to be demonstrated.
The record of natural disasters is too short for adequate understanding of human vulnerability. Using volcanology, climatology, history, anthropology, and tree rings, we extend the record by documenting a disaster to Inuit of extreme northwest America. Tree rings indicate the coldest summer in over 400yr in northwestern Alaska was in 1783, year of the Laki, Iceland eruption. European explorers reported famine and population decrease between 1779 and 1791. Anthropological studies indicate possible famine in nearby areas at around the same time. Inuit oral history describes extreme cold in summer causing famine and death a few centuries ago in northwest Alaska. We postulate that Laki, the unusual, cold-induced tree ring, and the recorded and oral histories of famine and death are all interrelated.
A persistent dry haze hung over Europe during the second half of 1783. Spawned by the Laki basalt fissure eruption in southern Iceland, this fog evoked much contemporary written commentary, from which the course of events is here reconstructed in a quantitative way. It was the densest European dry fog since the late Middle Ages, and it lay primarily in the troposphere. Spreading broadly toward the south and east, it nevertheless remained mostly confined to the North Atlantic, western Eurasia, and the Arctic. Previously it was believed by many to have risen to the middle stratosphere and to have blanketed much of North America. Composed of sulfuric-acid aerosols, its total mass reached about 200 megatons, as determined from its observed optical thickness. Several authors have pointed out that it may have been responsible for the cold winter of 1783–84, which caused much economic and social distress in many parts of the Northern Hemisphere. As the earliest dry fog to be studied scientifically, it remains the paradigm even today and poses an interesting challenge to climate modelers.
Speculating About the Weather: The Unusual Dry Fog of 1783
  • Katrin Kleemann
Kleemann, Katrin. "Speculating About the Weather: The Unusual Dry Fog of 1783." NiCHE, 2 Oct 2017.
Volcanoes, Climate Change, and Society: History and Future Prospects
  • Katrin Kleemann
Kleemann, Katrin. "Volcanoes, Climate Change, and Society: History and Future Prospects." Blog, 23 November 2017.
Scarth, Alwyn. Vulcan's Fury: Man Against Volcano. Hong Kong: World Print Ltd
  • David M Ludlum
  • Early American
  • Winters
Ludlum, David M. Early American Winters, 1604-1820. Boston: American Meteorological Society, 1966. Scarth, Alwyn. Vulcan's Fury: Man Against Volcano. Hong Kong: World Print Ltd, 1999.
Atmospheric and Environmental Effects of the
  • Thorvaldur Thordarson
  • Stephen Self
Thordarson, Thorvaldur, and Stephen Self. "Atmospheric and Environmental Effects of the 1783-1784
Laki Eruption: A Review and Reassessment
Laki Eruption: A Review and Reassessment." Journal of Geophysical Research 108 (2003).
A map of Iceland's geology. (This map was created by Katrin Kleemann and is built upon materials from Gingko Maps, CC BY 3
  • Fig
Fig. 3. A map of Iceland's geology. (This map was created by Katrin Kleemann and is built upon materials from Gingko Maps, CC BY 3.0 license.) 3. Impacts on North America