Dr. Scott Braun Principal Investigator

1. Dr. Scott BraunPrincipal Investigator

2. Hurricane Intensity Is Difficult To Predict Hurricane intensity forecasts have not improved much over the past many years Intensity prediction is difficult because it depends on weather at very large and very small scales

3. The Saharan Air Layer: Friend or Foe To Tropical Cyclones? The hot, dry, dusty SAL air mass has been argued to both favor and suppress tropical cyclone development Dry Saharan air Moist tropical air TS Isaac

4. Do Deep Thunderstorms Play a Fundamental Role? 3D view from NASA’s TRMM satellite

5. HS3 Will Use Two Global Hawks The “Environmental” GH Three 4-5 week deployments: 2012, 2013, & 2014 The “Over-Storm” GH

6. The Global Hawk Allows HS3 to Have Unprecedented Coverage and On-Station Time GH can fly this distance, dwell for 20 hours and return 1370 miles The Global Hawk can fly for up to 30 hours, allowing coverage of the entire Atlantic and on-station times of 10-20 hours. 3291 miles 10-hr dwell

7. HS3 Explores the Outflow of Leslie Hurricane Michael Date: September 6-7 Target: Hurricane Leslie Goal: Transit from Dryden to Wallops, examine the outflow structure of Leslie Hurricane Leslie

8. HS3 Explores Nadine’s Interaction With the SAL Date: September 11-12 Target: TS Nadine Goal: Examine whether SAL air is getting into Nadine’s circulation and perhaps slowing its development Tropical Storm Nadine SAL dust Sample data from the Cloud Physics Lidar Dust

9. HS3 Explores the Impact of Strong Wind Shear on Nadine’s Development Date: September 14-15 Target: TS/Hurricane Nadine Goal: To investigate how wind shear affects storm structure and intensification

10. Today’s Flight Into Nadine Goal: To determine how Nadine remains a tropical storm despite strong vertical wind shear, dry air, and cool ocean temperatures.

11. Achievements and Outlook For The Remainder Of The Mission • Many technical and logistical challenges • Excellent support from Dryden and Wallops • Successful flights into Leslie and Nadine • Dropsonde data getting into forecast models • Analysis yet to begin • Solved many problems that will improve operations in 2013-14 • Looking forward to two-aircraft operations

13. Instruments on the Environmental Global Hawk Scanning High Resolution Infrared Sounder (S-HIS) Airborne Vertical Atmospheric Profiling System (AVAPS) Cloud Physics Lidar (CPL) PI: Dr. Hank Revercomb University of Wisconsin Measurements: Upwelling thermal radiation at high spectral resolution between 3.3 and 18 microns. Temperature, water vapor vertical profiles PI: Dr. Matt McGill NASA Goddard Space Flight Center Measurements: Cloud structure and depth PI: Dr. Gary Wick NOAA, NCAR Measurements: Temperature, Pressure, wind, humidity vertical profiles; 89 Dropsondes per flight Atmospheric Temperature T (K) Thousands (feet) Turn Water Vapor Relative Humidity RH (%) Thousands (feet)

14. Instruments on the Over-StormGlobal Hawk Hurricane Imaging Radiometer (HIRad) High Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) High Altitude Monolithic Microwave integrated Circuit Sounding Radiometer (HAMSR) PI: Dr. Tim Miller NASA Marshall Space Flight Center Measurements: Surface wind speed, rain rate PI: Dr. Gerry Heymsfield NASA Goddard Space Flight Center Measurements: Radar reflectivity, wind profiles PI: Dr. Bjorn Lambrigtsen Jet Propulsion Laboratory Measurements: Temperature, water profiles, cloud liquid water