Tropical Cyclone Research at MIM
by Roger K. Smith
Research on the dynamics of tropical cyclones has been central activity in the Meteorological Institute for over 25 years. In the late eighties and nineties, the focus was on the dynamics of tropical cyclone motion, an activity that was generously supported by funding from the United States Office of Naval Research. An early highlight was an international field experiment, "The Tropical Cyclone Motion Experiment (TCM90)", that was organized to collect data on tropical cyclones over the Western North Pacific in support of theoretical and numerical modelling studies of these storms. Students and staff of the Institute participated in this experiment, which was based in Guam and Okinawa, and flew on the first mission of the National Aeronautics and Space Administration (NASA)'s DC8 research aircraft over a tropical storm.
The theoretical research carried out in Munich contributed significantly to an understanding of the basic dynamical mechanisms of vortex motion. A list of publications emanating from the research may be found here.
As numerical weather prediction models improved, tropical cyclone track forecasts improved considerably, but forecasts of intensity changes remain a challenge, as have forecasts of tropical cyclone formation. For this reason, during this century, the research focus, both within the international community and in the Meteorological Institute changed, with much more emphasis on the dynamics of formation and intensity change. Over the years, staff have had close collaboration with the National Atmospheric and
Oceanographic Administration (NOAA) Hurricane Research Division (HRD) in Miami, Florida and two staff members (myself and Dr. Sarah Jones) had the opportunity to fly into Atlantic hurricanes. A few MIM students have had the opportunity to visit the HRD also.
We have been involved in other field experiments including three to gather measurements related to tropical cyclogenesis: the "Tropical EXperiment in MEXico (TEXMEX)" held in Acapulco in July and early August 1991; the "Tropical Cyclone Structure experiment (TCS08)" held in the Western North Pacific in August-September 2008 and based in Guam; and the "Pre-Depression Investigation of Cloud Systems in the Tropics (PREDICT) experiment", which was based in St. Croix in the US Virgin Islands.
In the summer of 2006 I invited a colleague, Prof. Michael Montgomery, from the Naval Postgraduate School in Monterey, California, to visit Munich, the aim being to review what was understood about how tropical cyclones work and what was not. To provide a relaxed atmosphere in which to carry out our review, we rented a holiday house in Mittenwald. After a few days, we identified considerable gaps in knowledge and a lack in clarity in the relationship between competing theories at that time. This meeting set the scene for a close collaboration between my own group in Munich and Prof. Montgomery's group in Monterey and this has led to 70 joint publications at the time of writing. It resulted also in a textbook on tropical cyclones by myself and Prof. Montgomery.
In the following webpages, we present a contemporary view of the dynamics and thermodynamics of tropical cyclones to which the work of my group in the Meteorological Institute has contributed.
Latest version: Munich 27 December 2024