Earth science: Matching volcanic
eruptions to climate over the past 2,500
years *IMAGES*
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NATURE
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Climate sciences
Embargo
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London: Wednesday 08 July 2015 18:00 (BST)
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New York: Wednesday 08 July 2015 13:00 (EDT)
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Tokyo: Thursday 09 July 2015 02:00 (JST)
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Sydney: Thursday 09 July 2015 03:00 (AEST)
Large volcanic eruptions in the tropics and high-latitudes were important drivers of climate
variability in the Northern Hemisphere during the past 2,500 years, as a paper published
in Naturereveals this week. It is well known that volcanic emissions, particularly aerosols,
injected into the atmosphere increase the reflection of incoming solar radiation, thereby cooling
the Earth’s climate. However, this study is the first to match the climate record provided by tree
ring data unambiguously to the volcanic activity record on the basis of ice-core data from the past
2,500 years.
Comparing new measurements from Greenland and Antarctica ice cores with other well
established sources of information on climate variation, Michael Sigl and colleagues revise icecore timescales, showing that the ice-core record should be adjusted by seven years. They also
find that cooling was proportional to the magnitude of volcanic activity and persisted for up to ten
years after some of the largest eruptions.
As well as showing that volcanic eruptions had a robust cooling effect on climate over the past
2,500 years, the authors also suggest that particular volcanic eruptions and subsequent cooling
are linked to sixth-century plagues, famines and socioeconomic disruptions in Europe, Asia and
in the region around Central America.
Article and author details
1. Timing and climate forcing of volcanic eruptions for the past
2,500 years
Corresponding Author
Michael Sigl
Desert Research Institute, Reno, Nevada, United States
Email: msigl@dri.edu, Tel: +1 775 673 7383
DOI
10.1038/nature14565
Online paper*
http://nature.com/articles/doi:10.1038/nature14565
* Please link to the article in online versions of your report (the URL will go live after the embargo ends).
Image 1
Caption: Ice impurities are simultaneously analyzed at the Desert Research Institute’s Ultra-Trace
Chemistry Laboratory while continuously melting the ice section on a heated melter plate.
Credit: Sylvain Masclin
Image 2
Caption: A freshly drilled ice-core from TUNU, Greenland containing a history of volcanic eruptions is
pushed out of the core barrel.
Credit: Olivia Maselli
Image 3
Caption: Irish monastic foundation on the Scottish island of Iona, which may have been the location
where the 627 dust-veil observation was first made.
Credit: Francis Ludlow
Image 4
Caption: Bristlecone-pine (Pinus Longaeva) in the White Mts., California: Recorders of the climatic
impact of past volcanic eruptions over the past 5,000 years.
Credit: Michael Sigl