Observed Response of the Raindrop Size Distribution to Changes in the Melting Layer

Atmosphere

LawrenceD. Carey¹  KevinR. Knupp¹  PatrickN. Gatlin²  WalterA. Petersen² 

[1] Department of Atmospheric Science, University of Alabama in Huntsville, Huntsville, AL 35805, USA;NASA Marshall Space Flight Center, Huntsville, AL 35805, USA;

关键词: microphysics;    radar;    precipitation;   

DOI  :  10.3390/atmos9080319

来源: DOAJ

【 摘 要 】

Vertical variability in the raindrop size distribution (RSD) can disrupt the basic assumption of a constant rain profile that is customarily parameterized in radar-based quantitative precipitation estimation (QPE) techniques. This study investigates the utility of melting layer (ML) characteristics to help prescribe the RSD, in particular the mass-weighted mean diameter (Dm), of stratiform rainfall. We utilize ground-based polarimetric radar to map the ML and compare it with Dm observations from the ground upwards to the bottom of the ML. The results show definitive proof that a thickening, and to a lesser extent a lowering, of the ML causes an increase in raindrop diameter below the ML that extends to the surface. The connection between rainfall at the ground and the overlying microphysics in the column provide a means for improving radar QPE at far distances from a ground-based radar or close to the ground where satellite-based radar rainfall retrievals can be ill-defined.

【 授权许可】

Unknown