Master thesis topic: The impact of climate change on winter storm damage in Europe Severe European winter storms regularly induce significant damage on infrastructure. A poleward shift of the jet stream, as predicted in response to climate change, can bring storms into northerly parts of Europe, and global temperature change can increase their intensity, which may significantly worsen these impacts. The outcomes of such increased storminess over Europe is of great interest for society in general and especially for the (re-)insurance industry, due to the potential changes in the location and magnitude of the storm damages. Under climate change, dynamical factors can have opposing influences on storm track position and strength over Europe, rendering future projections a challenging task. Nevertheless, direct coupling with an impact model allows for the assessment of present and future storm risk under different scenarios.

Source: Wikipedia Goal: The goal of this work will be to evaluate the connection between climate change and the intensity and position of winter storms, including the assessment of present and future damage induced. Tools and Data:

§ ERA-Interim reanalysis data (https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era-interim) will be used to assess the connection between the large-scale circulation and the storm track.

§ The new generation of coupled models from the sixth phase Coupled Model Intercomparison Project (CMIP6) will be used to assess future projections of wind and storminess.

§ The CLIMADA model (https://wcr.ethz.ch/research/climada.html, Aznar-Siguan and Bresch, 2019) will be used to assess storm damages in Europe, using historical storms back to 1940 as well as findings from the CMIP6 for projections of future damage.

§ Optional: using data from Copernicus WISC (https://climate.copernicus.eu/windstorm-information-service, Röösli et al., 2018) for past windstorm events.

Research questions:

§ How does climate change affect the location and strength of storminess over Europe? § Are storm damages in CLIMADA increasing due to the poleward shift of storms?

Skills and prerequisites: The Master student should have a strong interest in researching fundamental findings and evaluating them in an applied framework. The student should have a background in atmospheric dynamics and the dominant weather patterns (e.g. from the classes by Heini Wernli and Christof Appenzeller), and ideally experience with the CLIMADA impact model (https://wcr.ethz.ch/research/climada.html, Aznar-Siguan and Bresch, 2019, e.g. from the lecture on uncertainty and risk by David N. Bresch and Reto Knutti) and good Python programming skills.

Supervision & Contact: Hilla Gerstman (ETH IAC) hilla.gerstman@env.ethz.ch Samuel Lüthi (ETH IED / MeteoSwiss) samuel.luethi@usys.ethz.ch Daniela Domeisen (ETH IAC) daniela.domeisen@env.ethz.ch David N. Bresch (ETH IED / MeteoSwiss) dbresch@ethz.ch Literature: Aznar-Siguan, G., and Bresch, D. N., 2019: CLIMADA v1: a global weather and climate risk assessment platform, Geosci. Model Dev., 12, 3085–3097. https://doi.org/10.5194/gmd-12-3085-2019

Befort, D. J., Wild, S., Knight, J. R., Lockwood, J. F., Thornton, H. E., Hermanson, L., et al. (2018). Seasonal forecast skill for extratropical cyclones and windstorms. Quarterly Journal of the Royal Meteorological Society. http://doi.org/10.1002/qj.3406

Renggli, D., Leckebusch, G. C., Ulbrich, U., Gleixner, S. N., & Faust, E. (2011). The Skill of Seasonal Ensemble Prediction Systems to Forecast Wintertime Windstorm Frequency over the North Atlantic and Europe. Monthly Weather Review, 139(9), 3052–3068. http://doi.org/10.1175/2011MWR3518.1

Oudar, T., Cattiaux, J., & Douville, H. (2020). Drivers of the northern extratropical eddy-driven jet change in CMIP5 and CMIP6 models. Geophysical Research Letters, 47, e2019GL086695. https://doi.org/10.1029/2019GL086695

Shaw, T. A., Baldwin, M., Barnes, E. A., Caballero, R., Garfinkel, C. I., Hwang, Y. T., ... & Voigt, A. (2016). Storm track processes and the opposing influences of climate change. Nature Geoscience, 9(9), 656-664. https://doi.org/10.1038/ngeo2783

Schwierz, C., Köllner-Heck, P., Zenklusen Mutter, E. et al. Modelling European winter wind storm losses in current and future climate. Climatic Change 101, 485–514 (2010). https://doi.org/10.1007/s10584-009-9712-1

Röösli, Thomas, David N. Bresch, and Marc Wüest. A comparison of the WISC events sets with both industry and research data: WISC Summary Report of Task 5.3–ETH/Swiss Re Case Study. ETH Zurich, 2018. https://doi.org/10.3929/ethz-b-000269483

Welker, C., Röösli, T., Bresch, D. N.: Comparing an insurer’s perspective on building damages with modelled damages from pan-European winter windstorm event sets: a case study from Zurich, Switzerland. https://www.nat-hazards-earth-syst-sci-discuss.net/nhess-2020-115. in review.

Sigg Remo, MSc thesis1: “The impact of persistent phases of the North Atlantic Oscillation on European winter storm damage”, ETH Zurich, Switzerland, 2020.

1 A previous collaboration between the research groups (Domeisen and Bresch).