Observations of Tropical Cyclones With the SSMIS

Passive microwave (PMW) radiometric observations of tropical cyclones (TCs) from the special sensor microwave imager/sounder (SSMIS) continue the legacy monitoring capabilities initiated with the special sensor microwave/imager (SSM/I) that began in 1987. The SSMIS has the following several important differences that should be factored into applications when compared to SSM/I data: 1) channel changes from 85 to 91 GHz result in a 2-8-K brightness temperature depression for many TC inner core scenes; 2) the inclusion of bore-sighted 150-GHz data can help in detecting rapidly growing convective cells that are frequently obscured by upper level clouds in visible and infrared data and are often associated with rapid intensification; and 3) the sensor swath increases by 300 km and permits enhanced spatial and temporal coverage of global TCs. All three attributes can be incorporated to maintain and/or enhance the satellite analyst´s ability to monitor critical TC structure via these PMW observations.