Satellite microwave detected SST anomalies and hurricane intensification

Sea surface temperature (SST) from the remotely sensed infrared measurements, like the GOES, AVHRR, and MODIS, etc., show missing values of SST over the cloudy regions associated with hurricanes. While satellite microwave measurements, like the Tropical Rainfall Measuring Mission (TRMM) microwave imager (TMI), can provide SST even under cloudy conditions. Both satellite microwave measurements and buoy observations show SST increase in advance of significant hurricane intensification. Moreover, hurricane intensification may also be related to the location of high SST. Our results indicate pre-existing high SST anomaly (SSTA) located at the right side of the storm track for Hurricane Katrina. Numerical simulations also confirm the important impacts of SSTA location on hurricane intensification. Similar situations are also found for Hurricanes Rita and Wilma. In contrast, if there is no high SSTA at the right location, hurricane may not undergo further intensification. This may explain why not all tropical cyclones associated with warm waters can attain peak intensity (categories 4 and 5) during their life cycle, and partially explains why hurricanes do not reach the maximum potential intensity as calculated only according to the magnitude of SST.