Airflow characteristics in the marine boundary layer over the Santa Barbara Channel during SCCCAMP. Part I. Summary of dual- Doppler radar observations

The two NOAA/Wave Propagation Laboratory 3 cm wavelength (X-band) pulsed Doppler radars were used during the South Central Coast Cooperative Aerometric Monitoring Program (SCCCAMP) to map the vertically averaged 2-D flow in the marine boundary layer (MBL) over the central and western portions of the Santa Barbara Channel. This is an area that has been poorly documented in the past and received relatively less intensive coverage by other measurement systems during SCCCAMP. The Doppler radar measurements, therefore, were used to fill a critical gap in our understanding of low-level mesocale flows in this region. Suitably strong radar echo was produced by X-band chaff released from two aircraft dedicated to this task. A dual-Doppler technique was used in which the two Doppler radars located at Gaviota and Santa Barbara were coordinated to scan through the volume in which echo was produced by the chaff. The measurements of the Doppler velocity from these two locations, about 46 km apart, is providing a more complete understanding of the 2-D characteristics of the Gaviota eddy, the mid-channel eddy, and other terrain-forced mesoscale flows that occur in the boundary layer over the Santa Barbara Channel.