Dr. Joss presented a seminar “TCIMS: A New Technique for Remote Measurement of the Intensities of Tropical Cyclones”.
From the “Carnot engine” model for the global thermodynamics of tropical cyclones, as developed by K. Emanuel and his collaborators, one can derive a formula relating the central sea-level pressure, Pc, of the storm to the altitudes, H, and temperatures, T, of the cloud tops within the storm’s eyewall, along with some additional readily available data. Among the parameters that determine Pc, H is by far the most difficult to measure remotely with sufficient accuracy (±100 meters). TCIMS is a space-based mission that will employ the parallax effect on multiple, nearly simultaneous images of the eyewall cloud tops, taken from satellites in both geosynchronous and low Earth orbits, to achieve the required precision measurements of H. I will describe ongoing experiments, in which we are using a combination of visible imagery from the International Space Station (ISS) and both visible and infrared imagery from Himawari 8, to test the accuracy and reliability of our method on western Pacific typhoons. In operational mode, TCIMS would employ a constellation comprising three nanosatellites, together with data from GOES-R series satellites and instruments mounted on the exterior of the ISS, to provide continuous worldwide monitoring of all strong (category 3 or higher) TCs within ±35º of the equator. For any given TC, TCIMS would measure Pc to an accuracy of ±3.5 hPa, at intervals averaging ~1 hr and almost never exceeding 1 hr 40 min for any given storm. These measurements would make it possible to alert governments and vulnerable populations to any abrupt changes in TC intensities prior to landfall. It may also be possible to improve the accuracy and reliability of TC forecasting with NWP codes by incorporating TCIMS measurements into the initialization.
The presentation is available on the anonymous ftp site: