Finding the potential height of tropical cyclone storm surges in a changing climate using Bayesian optimization

Simon D A Thomas , Dani Jones , Talea Mayo, John R Taylor, Henry B Moss, Dave Munday, Ivan D Haigh , Devaraj Gopinathan

We introduce a new framework for systematically exploring the largest storm surge heights that a tropical cyclone in a given climate can create. We calculate the tropical cyclone potential intensity and the potential size from climate model projections and find that both these limits increase in response to climate change. We then use Bayesian optimization with a barotropic ocean circulation model to find the maximum height that the surge can reach given these limits. The key methodological advances of this paper are (i) calculation of the recently proposed potential size of a tropical cyclone, now and under climate change (ii) using Bayesian optimization to find the largest storm surge given those constraints, (iii) using this information to constrain the return level curve. This paper uses key theoretical improvements in our understanding of tropical cyclones to understand implications for changing storm surge risk. We have chosen the US coastline and the area around New Orleans as our case study area, but this method is generalizable and could in principle be applied to any coastline.