Data / Science Data Products / VAPs

RWPVERTVEL

Radar Wind Profiler: In-cloud Vertical Velocity Retrieval

Evaluation VAP

The Radar Wind Profiler (RWP): In-cloud Vertical Velocity Retrieval value-added product (RWPVERTVEL VAP) is designed to provide vertical velocity retrievals in deep convective clouds. These clouds are first categorized into six cloud types—Convection, Stratiform, Bright Band, Bragg, General Cloud, and Cloud Free—based on Doppler velocity and spectrum width measurements (in the Radar Wind Profiler: Precipitation, corrected [RWPPRECIPCOR] VAP). Convection and Stratiform time instances are those where vertical velocity retrievals are performed with confidence.

Vertical velocities are retrieved following methodologies presented in Giangrande et al. (2013) for deep convective clouds at the Southern Great Plains (SGP) atmospheric observatory in Oklahoma based on Doppler velocity measurements from RWP and hydrometeor fall speed assumptions. Melting level height and temperature profile information obtained from the ARM Interpolated Sonde (INTERPSONDE) VAP are used to differentiate liquid from ice hydrometeors, where the fall speed assumptions are different. Note that the vertical velocities are not retrieved at the melting levels because of large uncertainties related to assumptions of relationships between melting particle fall speed and reflectivity.

Scientists can use RWPVERTVEL data for identification of different types of regions in deep convection (e.g., convective vs. stratiform) and retrievals of vertical velocity. Both RWPPRECIPCOR and RWPVERTVEL may also be processed for other ARM sites if the RWPs are configured similarly to the one at the SGP.

To ask questions, provide feedback, or report data issues, please contact VAP developer Aifang Zhou and/or ARM interim translator Scott Giangrande.