Visible or negligible? Impacts of the 17th century volcanic eruption on climate and society in early modern Switzerland

The considerable research on the effects of the 1815 Tambora eruption (Behringer 2015) has shown not only to what extent large tropical volcanic eruptions can transform a society but also how advantageous it is for research when geosciences and humanities interlink.

While single eruption events such as Parker in 1640/1641 have already been analysed (Stoffel et al. 2022), there has been less focus on the potential teleconnections of multiple eruptions on one single study area. This paper looks at the climatic and societal impacts of three tropical volcanic eruptions – Huaynaputina (1600), Komaga-take/Parker (1640/1641) and the 1690s unknown event – on Fribourg, a region in the western part of the Swiss Confederation.

To answer this research question meticulously, a transdisciplinary approach is required – both in method and sources. Daring to bridge geosciences and humanities, as part of the VICES research project we developed a data processing tool called ClimeApp, which facilitates the usage of climate data and makes transdisciplinary interaction more accessible, especially for researchers from the humanities (http://mode-ra.unibe.ch/climeapp).

Using ClimeApp, the climatological impact of these 17^th century eruptions will be assessed with modern climate reconstruction data from the state-of-the-art ModE-RA project (Valler et al. 2024). Novel archive material from municipal institutions – such as the Hôpital des bourgeois de Fribourg – allows us subsequently to determine the annually recorded harvest yields especially of the viti- and caseiculture. Additionally, essential archival sources, such as the Ratsmanuale (protocols) and the Mandatenbücher (regulations), depict whether the municipality of Fribourg deployed any measures or coping mechanisms in the wake of these volcanic eruptions. This combination of climatological data and historical sources enables us to look for potential interrelations between these climate anomalies and the effect they had on society.

The paper exemplary highlights on one side the advantages of research collaboration between two disciplines and on the other side sheds light on the possible impacts of multiple volcanic eruptions spanned over the period of almost hundred years on the same study region.