Impact of NASA Global Hawk Unmanned Aircraft Observations on Tropical Cyclone Track, Intensity and Structure: A Perspective from the NOAA SHOUT Program
HEDAS was developed as a research tool to assimilate high-resolution observations in tropical cyclones. It combines a state-of-the-art square-root ensemble Kalman filter, NOAA's HWRF modeling system, and a storm-relative processing capability for a variety of observation types. In 2013 and 2014, HEDAS was run in near real time on the NOAA Hurricane Forecast Improvement Project's Jet supercomputer to assimilate observations from NOAA and Air Force Reserve research and reconnaissance flights (dropwindsonde, flight level, Stepped-Frequency Microwave Radiometer, and Doppler radar data), satellite Atmospheric Motion Vectors, retrieved thermodynamic profiles from the Atmospheric InfraRed Sounder (AIRS) and Global Positioning System Radio Occultation (GPSRO), nearby rawindsondes, and Aircraft Communications Addressing and Reporting System (ACARS) on commercial aircraft.
In addition to the standard observation platforms assimilated in HEDAS mentioned above, the impact of three sounding platforms on the Global Hawk aircraft is investigated here for their impact. These platforms of interest are GPS dropwindsondes, retrieved thermodynamic profiles from the High Altitude Monolithic Microwave integrated Circuit (MMIC) Sounding Radiometer (HMSR), and retrieved thermodynamic profiles from the Scanning-High Resolution Interferometer Sounder (S-HIS). Results from data denial experiments from cases in 2013 and 2014 will be presented to illustrate the potential impact of these Global Hawk sounding platforms along with some preliminary ideas as to how to optimize their assimilation for tropical cyclones.