Atmosphere Ocean Science Colloquium

Tropical cyclones and climate risk science

Speaker: Adam Sobel, Columbia

Location: Warren Weaver Hall 1302

Date: Wednesday, November 16, 2022, 3:30 p.m.

Synopsis:

Climate risks are now being taken into account in an ever-widening range of human activities. By a “climate risk” I mean the probability of some particular loss to human society or ecosystems from climate-related hazards. Risk is the product of hazard (the component related to climate; e.g., the probability of a given level of flooding, heat, wind, etc.), exposure (the assets at risk, which can include human or nonhuman lives as well as buildings and infrastructure), and vulnerability (the fraction of those assets lost for a given level of hazard).  Each can be represented with different degrees of complexity, different balances of empiricism vs. first principles, and different spatial or temporal resolutions. For the better part of a decade, our group at Columbia has been doing research on tropical cyclone risk, using an original statistical-dynamical model that generates synthetic tropical cyclones given input data on the large-scale climate (e.g., from a reanalysis or climate model). Some of our work is in collaboration with partners in the insurance industry, but we are also increasingly involved in collaborations with NGOs in support of climate adaptation or disaster risk reduction. At first we only modeled the hazard --- the storms themselves --- but now we are also beginning to model exposure and vulnerability as well. I will present some results from this work, and discuss some of the trade-offs and challenges. While I will focus on tropical cyclones, many of the issues are common to other aspects of climate risk.