NRL tropical cyclone R&D web resource augmentations

The NRL tropical cyclone (TC) web page highlights unique satellite microwave products enabling unparalleled views of tropical cyclone storm structure, intensity and location. The ability to routinely map tropical cyclone rainbands and eyewall evolution regardless of upper-level clouds represents a key supplement to routine geostationary visible/IR imagery. Although polar orbiter microwave imagery can “see through” non-raining clouds, the data set inherently suffers from poor temporal sampling. This has been partially mitigated by creating a “constellation” of microwave sensors using both operational and research satellites.

The constellation has recently been augmented with near real-time Coriolis WindSat and Special Sensor Microwave Imager Sounder (SSMIS) data provided by the Fleet Numerical Meteorology and Oceanography Center (FNMOC). WindSat's 2m dish provides superb 37 GHz imagery at high spatial resolution (identical to the microwave imager on the Tropical Rainfall Measuring Mission, TRMM TMI) that resolves key storm structure not possible with poorer resolution Special Sensor Microwave/Imager (SSM/I) data sets. WindSat's orbital attributes permit this sensor to provide enhanced spatial and temporal coverage since it compliments the SSM/I sampling. The SSMIS continues the SSM/I heritage and ensures sustained coverage at 85 GHz begun in 1987. The SSMIS data set not only boosts the reliability of the current SSM/Is, but also permits collocated imager/sounder combinations that are still experimental.

In addition, NRL has added several key high-resolution data sets via polar orbiter sensors; a) night time visible from the Operational Linescan System (OLS), and b) 250-m, 500-m and 1-km visible and 1-km IR data from the NASA Moderate resolution Imaging Spectroradiometer (MODIS). Sufficient lunar illumination permits analysts to view storm cloud structure at night with detail not feasible in IR imagery. MODIS data contains superb spatial resolution that enhances the analysis of low-level circulation centers and cloud convergence zones, over shooting tops, and inner eye vortices. All data sets are available in near real-time with the exception of the 3-hour delay mandated with all OLS products. These upgrades are being phased into the Navy's operational TC web page hosted FNMOC, collocated with NRL in Monterey, CA.