Climate Change Impact on Midlatitude Cyclone Intensity, Tracks, and Impacts (CLIM-CITI)

Extratropical cyclones (ETCs), also known as midlatitude storms or windstorms, in the Northern Hemisphere typically track across the North Pacific into the US and across the North Atlantic into Europe. The storms that track into Europe cause billions of Euros of damage each year due to their strong winds and heavy rain. Our current best estimates of how these European storms will change in the future are very uncertain, meaning that it is difficult for governments and industry to make decisions about how to adapt to potential future changes. The state-of-the-art climate models we use to make projections have improved over the past 20 years or so, but they still struggle to correctly represent the midlatitude storms and where they track. In this project we want to take a new approach to the evaluation of these climate models in order to gain deeper understanding of the reliable aspects of the models, the relevance of model grid-spacing, what needs to be improved through further model development, and how we can use this insight to make better future projections. We cannot simply wait for the next generation of higher-resolution climate models and hope for the storm tracks to be better represented. This approach will consider the ways in which the storms develop and become stronger, allowing us to group similar storms for analysis. The ambitious approach is now possible due to (1) an increase in the number of variables available from the most recent climate model simulations, and (2) the combined expertise of the project investigators. The outcomes of this project will inform model development efforts, and have the potential to provide a mechanism for more optimally combining the future projections of different climate models in order to have better confidence in these future projections. We will discuss with the Environment Agency to ensure the results can be useful to their efforts to improve climate resilience and enhance disaster risk management. We will also discuss our results with reinsurance companies who are considering the impacts of climate change on the vulnerability of their property portfolios.