Volcanic air pollution from Reykjanes eruptions in Iceland
Summary
A volcano has woken up after an 800-year long pause in the most densely populated part of Iceland, the Reykjanes peninsula. The frequent lava eruptions are causing significant air pollution of sulfur dioxide (SO2) and particulate matter (PM) across Iceland. The volcanic air pollution has on several occasions also reached the United Kingdom.
Your PhD project will investigate the intensity and dispersion patterns of volcanic air pollutants (SO2, PM1, PM2.5, PM10) in populated areas during prolonged basaltic eruptions using the densest air quality monitoring network in any volcanic area in the world. The project will involve fieldwork in Iceland during and in between volcanic eruptions and a close collaboration with key operational agencies in Iceland – the Environment Agency of Iceland and the Icelandic volcano observatory.
Volcanic eruptions near urban areas lead to higher human exposures because of their proximity to communities; and both large and small, ash-poor fissure eruptions can cause severe air pollution episodes of gas and particulate matter and impact people’s health (Carlsen et al., 2021; Ilyinskaya et al., 2017; Whitty et al., 2020). At the time of writing in November 2024 there have been 9 eruptions on Reykjanes with the 10th one expected before the end of the year. Magma accumulation continues and, based on the eruption history of Reykjanes, eruptive episodes activity may continue for decades or even centuries.
Project parts
1. Very fine-scale dispersion patterns of volcanic air pollutants
Our team discovered during the first modern Reykjanes eruption in 2021 that there were significant fine-scale temporal (≤1 hour) and spatial (<1 km) fluctuations in SO2 and PM air pollutant concentrations in populated areas, but these remain unexplained.
Currently, the Reykjanes peninsula and the nearby Reykjavik capital area has the densest reference-grade air quality monitoring network of any volcanic area in the world, with over 20 reference-grade operational air quality stations within 40 km distance from the volcano. It is also the only volcanic area where reference-grade PM1 measurements are collected.
You will investigate the very fine-scale fluctuations in the dispersion patterns and intensity using the dense reference-grade network and you will augment it further by installing a high number of lower-cost sensors in the field.
2. Mixing of volcanic and urban air pollutants

Volcanic emissions and urban air pollution sources, respectively, are known to contain many chemical compounds that are hazardous to health. While these distinct end member compositions are better known, their mixing has not been studied. Especially interesting are emissions from lava-urban interfaces (LUI), where structures are being burned by lava. LUI emissions likely have unique chemistry due to the combination of volcanic and human-made compounds. The interaction impacts the combustion process, the composition of the emissions released into the environment, and the chemical reaction pathways in the atmospheric plume. The LUI interaction may also be modifying the degassing processes in the lava, and release of magmatic volatiles.
You will collect geochemical and atmospheric samples of gases and PM of the different pollution sources and their mixes, including at active eruption sites. You will analyse the samples in laboratories using a variety of methods, including ion chromatography, mass spectroscopy and microscopy.
3. Volcanic contribution to PM1 levels in Iceland and the UK
We discovered that the 2021 Reykjanes eruption caused an unequivocal eruption-related increase in relative and absolute PM1 abundance, suggesting that ash-poor eruptions are one of, or the most, important source of PM1 in Iceland, and potentially in other areas exposed to volcanic emissions. In 2024, at least three Reykjanes eruptions negatively impacted air quality in the UK with respect to SO2 and PM, but this has not been quantified or researched further.
PM1 is only recently being introduced in operational air quality monitoring worldwide and evidence-based guidelines for its levels are not yet established. Available studies unequivocally demonstrate a correlation between increased concentrations of PM1 and negative health outcomes and high-quality datasets on levels and variability of PM1 are therefore important steps towards establishing air quality guidelines.
You will work with data from reference-grade PM1 instruments and collect PM samples to understand the volcanic impact on PM1 levels in both Iceland and the UK.
References
Carlsen, H.K., Ilyinskaya, E., Baxter, P.J., Schmidt, A., Thorsteinsson, T., Pfeffer, M.A., Barsotti, S., Dominici, F., Finnbjornsdottir, R.G., Jóhannsson, T., Aspelund, T., Gislason, T., Valdimarsdóttir, U., Briem, H., Gudnason, T., 2021. Increased respiratory morbidity associated with exposure to a mature volcanic plume from a large Icelandic fissure eruption. Nature Communications 12, 2161. https://doi.org/10.1038/s41467-021-22432-5
Ilyinskaya, E., Schmidt, A., Mather, T.A., Pope, F.D., Witham, C., Baxter, P., Jóhannsson, T., Pfeffer, M., Barsotti, S., Singh, A., others, 2017. Understanding the environmental impacts of large fissure eruptions: Aerosol and gas emissions from the 2014–2015 Holuhraun eruption (Iceland). Earth and Planetary Science Letters 472, 309–322.
Whitty, R.C.W., Ilyinskaya, E., Mason, E., Wieser, P.E., Liu, E.J., Schmidt, A., Roberts, T., Pfeffer, M.A., Brooks, B., Mather, T.A., Edmonds, M., Elias, T., Schneider, D.J., Oppenheimer, C., Dybwad, A., Nadeau, P.A., Kern, C., 2020. Spatial and Temporal Variations in SO2 and PM2.5 Levels Around Kīlauea Volcano, Hawai’i During 2007–2018. Front. Earth Sci. 8. https://doi.org/10.3389/feart.2020.00036