NASA High-Altitude Precipitation/Wind Radars for Hurricane Research
Gerald Heymsfield (firstname.lastname@example.org)
NASA Goddard Space Flight Center
Li, University of Maryland Baltimore
Carswell, Remote Sensing Solutions
Schaubert, University of Massachusetts
Cretico, University of Massachusetts
NASA has been flying high-altitude (60-70k ft) downlooking Doppler radars on the NASA ER-2 aircraft for the past decade. These radars include the X-Band ER-2 Doppler Radar (EDOP) and the W-Band Cloud Radar System (CRS) which are primarily nadir viewing and obtain high resolution images of reflectivity and vertical hydrometeor motions in cloud and precipitation regions. Numerous tropical storms were overflown with EDOP during NASA’s CAMEX-3, CAMEX-4, and EDOP and CRS during TCSP. These resulted in various studies from Hurricanes Bonnie and Georges in 1998, Tropical Storm Chantal and Hurricane Erin in 2001, and Hurricanes Emily, Dennis, and Gert in 2005. The EDOP and CRS radars are not suitable for deriving the full horizontal wind from high-altitudes above storms that is of extreme interest in inner core regions of hurricanes. Recently, the Imaging Wind and Rain Airborne Profiler (IWRAP) has demonstrated a conical scan radar approach from the NOAA P3 to derive winds at the surface and in precipitation regions.
Our recent work has focused on horizontal wind measurements in storms with use of conical scan radar from both manned and high-altitude UAV (HUAV) platforms. Two systems under development at NASA Goddard are: the X-band UAV Doppler Radar (URAD) and the dual-wavelength (Ku and Ka band) High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP). These radars are designed for measuring tropospheric winds within precipitation regions and ocean surface winds in rain-free to light rain regions. Both systems are designed for the Global Hawk HUAV with initial flights of HIWRAP planned for the NASA WB-57 manned aircraft (60-65kft ceiling) during Summer 2008. HIWRAP uses new technologies that utilize solid state rather than tube based transmitters such as used in URAD. The presentation will discuss the motivation for HIWRAP and URAD, a description of the instruments, and their potential use in hurricanes.