On the Improvement to H*Wind Hurricane Wind Analyses Due to the Inclusion of Future Ocean Surface Wind Measurements from Aircraft and Satellite Timothy L. Miller 1, R. Atlas 2, P. G. Black 3, S. S. Chen 4, R. E. Hood 1, J. W. Johnson 5, L. Jones 5, C. S. Ruf 6, and E. W. Uhlhorn 2 1 NASA/MSFC, Huntsville, AL 2 NOAA/AOML, Miami, FL 3 SAIC Inc., Naval Research Laboratory, Monterey, CA 4 University of Miami, Miami, FL 5 University of Central Florida, Orlando, FL 6 University of Michigan, Ann Arbor, MI Presented to Working Group on Space-Based Lidar Winds, Feb. 2008

Hurricane Imaging Radiometer (HIRAD) Existing 1980s Technology Advanced Technology HIRAD in development Simulated Observations HIRAD utilizes NASA Instrument Incubator Technology: Provides unique observations of sea surface wind, temp and rain Advances understanding / predictability of hurricane intensity Enhances Stepped Frequency Microwave Radiometer capabilities Uses synthetic thinned array tech. of Lightweight Rain Radiometer Employs sensor web tech. for innovative information management Univ. of Michigan Univ. of Alabama/Huntsville Univ. of Central Florida NASA NOAA Ms. Robbie Hood, PI NASA/MSFC Earth Science Dr. Timothy Miller, Co-I NASA/MSFC Earth Science Dr. Peter Black, 40 yrs, hurricane research Mr. James Johnson, 30 yrs, microwave remote sensing Dr. Linwood Jones, 35 yrs, microwave remote sensing Dr. Christopher Ruf, 23 yrs, passive microwave technology Mr. Eric Uhlhorn, NOAA Hurricane Research Division NASA/UAH Engineering & Spacecraft Project Management Expert Team Passive Microwave C-Band Radiometer Freq: 4, 5, 6 & 7 GHz, Version 1 H-pol for ocean wind speed, Version 2 dual-pol for ocean wind vectors 11 km Aircraft Altitude Performance Characteristics EIA: 0°- 60°, Spatial Resolution: 1-2 km, Swath: ~30 – 40 km Observational Goals: Wind Speed 10 - >85 m/s Rain Rate 0 - > 100 mm/hr 2000 km Swath

Technology Transfer Operational Reconnaissance Hurricane Aircraft (optional) Unmanned Aerial Vehicle Demonstration (optional) Technology Brassboard Demonstration in Laboratory Satellite Demonstration of Improved Hurricane Ocean Surface Vector Winds and Rain Rate HIRAD Technology Investment Roadmap Aircraft Demonstration

Hurricane Imaging Radiometer Univ. of Michigan Univ. of Alabama/Huntsville Univ. of Central Florida NASA NOAA HIRAD Team Benefit of MSFC Investment HIRAD Development Timeline

Motivation for HIRAD OSSE High-resolution ocean surface wind measurements expected to give improvements in near real-time analyses of ocean surface wind speed –Specific product targeted: NOAA HRD H*Wind, regarded as “best analaysis” of hurricane near-surface wind; produced after reconnaissance aircraft –Would also expect improvement in numerical weather prediction, but that OSSE is beyond the present scope of work OSSE requires “nature run” (i.e. high-resolution model forecast) to enable simulation of instrument observations, including hi-res details –Provided by Dr. Shuyi Chen, Univ. of Miami Non-hydrostatic MM5, interactive ocean and wave models Horizontal grid resolution degrees (~1.5 km) for innermost nest –Case is Hurricane Frances, Aug-Sept 2004

Simulated Observations Quick-Scat (existing ocean surface winds satellite) Univ. Central Florida Cases include full swath over storm, partial swath SFMR (aircraft ocean surface winds sensor) Univ. Central Florida Winds along ground track; no cross-track structure Flight-level windsNOAA Hurricane Research Div. Dropsonde windsMSFC Drops in eyewall and at storm center from aircraft Airborne Doppler RadarNOAA HRD GOES cloud windsMSFC Using actual data for location, nature run data for wind values. Buoys, ships, coastal sensorsNOAA HRD Not needed for cases over open ocean HIRADUniv. Central Florida 2 aircraft altitudes, satellite

Nature Run Wind Speed, Rain Rate  = 20 mm/hr

H*Wind from “perfect” nature run data wind speed max = 125 knots

Conventional SFMR, sonde, Quikscat Max. Obs. WS 110 kts Max. Analyzed WS 109 kts

Hirad 3 km Hirad, sonde, Quikscat Max. Obs. WS 118 kts Max. Analyzed WS 117 kts

Hirad 11 km Hirad, sonde, Quikscat Max. Obs. WS 122 kts Max. Analyzed WS 121 kts

Hirad Satellite only (no A/C) Max. Obs. WS 105 kts Max. Analyzed WS 105 kts

Quikscat, GOES (no aircraft) Max. Obs. WS 82 kts Max. Analyzed WS 82 kts

Summary HIRAD instrument will measure ocean surface wind speed (vectors in next phase) up to ~100 m/s through rain up to ~100 mm/hour. (Will also measure rain rate and temperature.) –Primary application considered: tropical cyclones; would presumably also be of value in mid-latitude storms –Does not measure low-speed winds (<~10 m/s) – not a replacement for scatterometer (or lidar), but rather complementary “Quick” OSSE demonstrates positive impact on NOAA/AOML/HRD’s H*Wind analysis product –Adding swath width to current airplane capability would better define vortex, increase probability of capturing max wind –HIRAD satellite would provide excellent representation of vortex, even in the absence of reconnaissance aircraft (not true of scatterometer) Possible future OSSEs will quantify impact on NWP