WB-57F High Altitude Hurricane Observation Profiling Suite – Science Capabilities

Abstract:

Improvements to TC/hurricane intensity forecasts may depend on routine spatially-dense measurements of thermodynamic temperature/water vapor profiles, sea surface winds, clouds and precipitation. Both high vertical resolution (~10-100 meters) within the air-sea boundary layer, and high horizontal resolution (~1-10 km) are needed, with particular emphasis on the eyewall and rainband regions. Such observations cannot be obtained from satellites, but require airborne assets with appropriate instrumentation. We describe a suite of research quality instruments for hurricane reconnaissance from the NASA WB-57F aircraft platform. The High Definition Sounding System automatically deploys up to 90 XDD dropsondes for simultaneous high resolution PTU+Winds vertical profiles and SST, while an array of active and passive remote sensing instruments map thermodynamic and cloud/precipitation variables. The XDD is a lightweight GPS dropsonde providing thermodynamic curtain in-situ measurements as densely as km-scale spacing. The airborne profiling radiometers include water vapor, temperature, cloud, precipitation, and ocean surface wind imaging. These instruments use both staring and conical scanning polarimetric radiometry techniques. Of specific interest will be dense boundary layer profiling and upper atmospheric humidity, which historically have been very challenging measurements. A unique 183 GHz radiometer will provide calibration closure for polymer-based humidity sensors used by all dropsondes. Polymer sensors are well known to suffer from a so-called "dry bias" calibration error. The poster will describe the collective capabilities of this new observational platform and show data from past deployments on a variety of NASA and Navy research aircraft.