Vertical Distribution of Radar Reflectivity, Moisture, and Thermodynamic Variables in Hurricanes in the Presence of Shear

Aircraft radar and dropsonde data from the intense Hurricanes Katrina (2005) and Rita (2005) observed in RAINEX and Hurricane Earl (2010) observed in GRIP are analyzed to determine the effect of shear strength on the vertical structure of both reflectivity and thermodynamic variables in relation to eyewall and rainband convection. Katrina, Rita, and Earl had differing degrees of environmental shear and therefore these datasets offer a good opportunity to examine how the convection in strong storms responds to shear. We characterize the frequency with which particular reflectivities occur at all altitudes to diagnose the convective behavior of each shear-relative quadrant by following the methodology applied by Hence and Houze in recent papers to over 10 years of TRMM Precipitation radar data. By using this methodology we determine whether strong storms intensively sampled by aircraft conform to the statistics obtained by TRMM. We use contoured frequency by altitude diagrams (CFADs) and compare the aircraft CFADs to the satellite CFADs. We further create composite analyses of dropsonde data for each quadrant of the storm (relative to the shear vector) to facilitate interpretation of the CFADs in terms of storm dynamics, thermodynamics and moisture stratification. Both RAINEX and GRIP featured extensive dropsonde sampling in all quadrants of Katrina, Rita, and Earl. All of these storms obtained dropsondes from P3 aircraft flying at midlevels. Since GRIP employed the DC-8, the dropsondes were obtained from higher altitude, so the Earl dataset will allow for analysis of deeper-layer thermodynamics. This study paves the way for future use of the Global Hawk dropsonde and remote sensing datasets to be obtained over the next few years.