Health impact of large Icelanic eruptions
What if a Laki-style eruption were to happen tomorrow? Volcanic eruptions have a huge potential to affect the climate system, environment and society. Given the complex socio-economic framework we live in, the modern-day society is increasingly vulnerable to the hazards and risks arising from volcanic eruptions.The recent eruptions of the Icelandic Eyjafjöll and Grímsvötn volcanoes demonstrated the vulnerability of society (and of aviation in particular) to volcanic ash. However, a close inspection of the Icelandic geological record shows that “volcanic ash-clouds” are only half the story because there have been at least four volcanic eruptions during the last 1,150 years that released huge amounts of sulphur dioxide (gas) into the atmosphere (instead of volcanic ash). The best-studied example is the eight-month-long eruption of Laki in 1783–1784 AD, which caused extreme environmental stress and has been linked to an increase in mortality rates in several countries in Europe during the summer of 1783.
Given these historic records, we ought to ask ourselves: “What if a Laki-style eruption were to happen tomorrow?”. As part of her PhD project, Anja Schmidt led a study aiming to assess the potential hazards created by a future Laki-style Icelandic eruption for modern-day society.
Using GLOMAP-mode, we simulated a Laki-style eruption as it happened in 1783 but under present-day atmospheric conditions. Such an eruption would release huge amounts of sulphur dioxide (about 122 Mt) into the atmosphere – more than all global man-made sulphur emissions in a whole year. The work shows that the resulting aerosol cloud consisting of tiny sulphate particles, will be dispersed across the European continent potentially creating a severe public health hazard.
In order to quantify the public health risk arising from the increase in acidic air pollution due to such an eruption, we used current epidemiological functions that link changes in air pollution to changes in a given health risk. We found that, based on the modelling results, a future Laki-style volcanic air pollution event could cause up to 142,000 premature deaths in Europe within a year – many more than the number of people who die from seasonal flu each year. Overall, our work has implications for policy-makers, governmental bodies and the aviation industry, and highlights the need to discuss the appropriate risk mitigation strategies.
The paper “Excess mortality in Europe following a future Laki-style Icelandic eruption” has recently been published in PNAS.
The research was a collaboration between Dr. Anja Schmidt, Professor Ken Carslaw, Professor Marjorie Wilson and Dr. Graham Mann from the University of Leeds; Dr. Bart Ostro from the Centre for Environmental Epidemiology in Barcelona, Spain and the California Environmental Protection Agency; Dr. Thor Thordarson of the University of Edinburgh; and Professor Adrian Simmons from the European Centre for Medium-Range Weather Forecasts in Reading. You can download a copy (open access) using the link Schmidt et al (2011)
See also Anja’s page at: http://homepages.see.leeds.ac.uk/~earasc/research.html The study also received coverage in the media, for example: Science Now and Wired News Der Spiegel and several Icelandic print and online magazines, for example: Visir and Pressan