Polarimetric Radar Observations of Dust Storms at C- and S-Band

Wind-lofted particles in dust storms exhibit repeatable polarimetric radar characteristics in one C-band and three S-band datasets, including reflectivity factor (Z(H)) <25 dBZ and copolar cross-correlation coefficient (rho(hv)) <0.65 (and often <0.50). Differential reflectivity (Z(DR)) varies substantially in dust storms, with values averaging <0 dB in an Arizona case and + 1.5 to + 4 dB in two southern Plains cases. C-band Z(DR) was generally + 1 to + 3 dB in a Kuwait dust storm, similar to the southern Plains cases. Z(DR) may exhibit small patches of values <-3 dB, especially when observing at an altitude <0.5 km above radar level. Whereas dusty and nondusty convective outflow boundaries may have similar Z(H) characteristics, non-dusty boundaries may be differentiated by their relatively higher Z(DR) and rho(hv) values.