Hurricane Observation Capability of Future Hurricane Imaging Radiometer (HIRAD)

Timothy L. Miller1, R. Atlas2, P. G. Black3, R. E. Hood5, M. W. James1, J. W. Johnson6, L. Jones6, C. S. Ruf7, E. W. Uhlhorn2, and Salem Al-Nimri6

1NASA/MSFC, Huntsville, AL2NOAA/AOML, Miami, FL

3SAIC Inc., Naval Research Laboratory, Monterey, CA4USRA, Marshall Space Flight Ctr, Huntsville, AL

5NOAA, Boulder, CO6University of Central Florida, Orlando, FL

7University of Michigan, Ann Arbor, MI

Presented to Interdepartmental Hurricane Conference, March 2009

Hurricane Imaging Radiometer (HIRAD)

Existing1980s Technology

Advanced TechnologyHIRAD in development

Simulated Observations

HIRAD utilizes NASA Instrument Incubator Technology:• Provides unique observations of sea surface wind, temp and rain• Advances understanding / prediction of hurricane intensity• Expands Stepped Frequency Microwave Radiometer capabilities• Uses synthetic thinned array, RFI mitigation technology of Lightweight Rain Radiometer

Univ. of Michigan

Univ. of Alabama/Huntsville

Univ. of Central Florida

NASA

NOAA

• Timothy Miller, PI, NASA/MSFC Earth Science• Eric Uhlhorn, co-PI, NOAA AOML/Hurricane Research Division • Robbie Hood, NOAA UAV Program Mgr, co-I and former PI• Linwood Jones, University of Central Florida • Christopher Ruf, University of Michigan• NASA/UAH Engineering & Spacecraft Project Management• Peter Black, NRL/SAIC• Robert Atlas, NOAA/AOML

Government, Academic Team

Passive Microwave C-Band RadiometerFreq: 4, 5, 6 & 6.6 GHz, Version 1 H-pol for ocean wind speed, Version 2 fully polarimetric for ocean wind vectors20 km Aircraft Altitude Performance CharacteristicsEIA: 0°- 60°, Spatial Resolution: 2-5 km, Swath: ~70 kmObservational Goals:Wind Speed 10 - >85 m/s Rain Rate 0 - > 100 mm/hr

2000 km Swath70 km

What is HIRAD?(Hurricane Imaging Radiometer)

• Passive C-band radiometer• Objective: To measure strong ocean surface winds through heavy rain from air

or space-based platform– With cross-track resolution in addition to along-track– Swath width ~60o (~3 x altitude)– Winds dynamic range: 10 – 100 m/s, through rain up to ~100 mm/hr– Would complement scatterometers and lidars

• Technology heritage:– SFMR (Stepped-Frequency Microwave Radiometer) currently flying on reconnaissance

aircraft (no cross-track resolution)– NASA Instrument Incubator: Thinned array antenna, along-track real aperture, synthetic

cross-track aperture• Status:

– Brassboard (bench lab) version of single-polarization (wind speed only) instrument successfully tested in anechoic chamber last August

– Single-polarization aircraft instrument to be completed Sept. 2009• Partnership:

– Project leadership, PI, and engineering at NASA/MSFC– Technology, engineering, and science lead partners: NOAA/HRD (Uhlhorn), Univ. Central

Florida (Linwood Jones), Univ. Michigan (Chris Ruf), Univ. Alabama Huntsville (project & engineering support)