[Houghton Lecture] Kerry Emanuel (MIT) — Reduced Models of Tropical Cyclones

Abstract:
Reduced models of physical, chemical and biological systems aim to improve understanding of phenomena by throwing away all this is not essential to distill the essence of the phenomenon. This can be contrasted with, e.g., numerical weather prediction, whose aim is to make the most accurate forecast possible. In this lecture I will describe a highly reduced numerical model of tropical cyclones, phrased in a coordinate system in which the radial coordinate is a conserved variable, angular momentum, and show that the resulting system is far less nonlinear and simpler to understand. I will use this model to show that TC eyewalls are examples of atmospheric fronts, and to illustrates the basic physics of eye formation.

About our speaker:
Dr. Kerry Emanuel is the Cecil and Ida Green post-tenure professor of atmospheric science at the Massachusetts Institute of Technology, where he was on the faculty from 1981 to 2022. Before that he was on the faculty of UCLA from 1978 to 1981.

Emanuel’s initial focus was on the dynamics of rain and snow banding in winter storms, but his interests gradually migrated to the meteorology of the tropics and to climate change. His specialty is hurricane physics and he was the first to investigate how long-term climate change might affect hurricane activity, an issue that continues to occupy him today. His interests also include cumulus convection, and advanced methods of sampling the atmosphere in aid of numerical weather prediction.

Emanuel is the author or co-author of over 300 peer-reviewed scientific papers, and three books, including Divine Wind: The History and Science of Hurricanes, published by Oxford University Press and aimed at a general audience, and What We Know about Climate Change, published by the MIT Press and now entering its third edition. His graduate textbook “Physics of the Tropical Atmosphere and Tropical Cyclones” will be published by Princeton University Press in 2026. He was a co-founder and co-director of MIT’s Lorenz Center, a climate think tank devoted to basic, curiosity-driven climate research. He is the Chief Scientific Officer and co-founder of WindRiskTech, LLC, which provides clients with advanced synthetic tropical cyclone events sets for assessing current and future tropical cyclone risks worldwide.

Houghton Lecture Series

Supported by the Houghton Fund, Houghton Lecturers are distinguished visitors from outside MIT, invited by the EAPS Program in Atmospheres, Oceans and Climate (PAOC) to spend a period of time, ranging from a week to several months, as scientists-in-residence.

Contact: kbauer@mit.edu