ARMAR observations during TOGA/COARE

The NASA/JPL Airborne Rain Mapping Radar (ARMAR) was deployed for rainfall observations during TOGA/COARE on the NASA DC-8 aircraft. A total of /spl sim/30 hours of rain profiling measurements were collected over the Western Pacific Ocean during January and February 1993. The rain systems observed included isolated convective cells, mesoscale convective complexes, and a tropical cyclone. The authors' preliminary results show that the radar bright bands of the observed stratiform rain were typically located at or above 4.5 km, although occasionally some appeared at altitudes as low as 4.1 km. The results also show relatively large reflectivity variations in stratiform rain. In the authors' rain attenuation study, they show that the radar surface reference technique and the radiometer technique produce similar path-integrated attenuation estimates for one-way attenuations /spl les/4 dB. The radar technique, however, has the potential of providing accurate estimates at larger attenuations when the radiometer is saturated. The dual-polarization radar profiling measurements show that the local extrema of Z/sub DR/, /spl rho//sub hv/ /spl phi//sub hv/ occurred near the bottom of the melting layer. These extrema were probably caused by the presence of varying mixture of hydrometeors with various shape, size, and thermodynamic phase.<<ETX>>