Polarimetric radar vertical profiles’ climatology in continental/tropical MCSs and hurricanes
Ryzhkov, Alexander — NOAA - National Severe Storms Laboratory
Hu, Jiaxi — Cooperative Institute for Severe and High-Impact Weather Research and Operations
Area of research:
Various cloud systems, including 13 continental MCSs, 10 marine MCSs, and 11 landfalling hurricanes, were investigated with operational WSR-88D weather radars using novel methodologies for processing and visualizing radar data such as RD-QVP and CVP. A comprehensive climatology of the vertical profiles of polarimetric radar variables and radar-derived ice/liquid water content, mean volume diameter of particles, and their total number concentration has been created.
This climatology provides a benchmark for evaluation and improvement of cloud models and demonstrates the unique ability of operational polarimetric weather radars to generate such products anywhere and anytime.
Most cloud models tend to overestimate the size of cloud ice particles and underestimate their concentration. This emphasizes the need to provide a reliable observational reference to optimize cloud model performance, particularly in areas of high concentration of ice at high altitudes. The dual-polarization radars give the community a unique opportunity to quantify cloud ice with good accuracy using polarimetric radar retrievals. In this study, we use the network of operational WSR-88D radars to build a climatology of the vertical profiles of radar variables such as radar reflectivity Z, differential reflectivity ZDR, and specific differential phase KDP as well as the radar-retrieved vertical profiles of ice water content (IWC) above the melting layer and liquid water content (LWC) below it, mean volume diameter Dm, and total number concentration Nt of ice and liquid particles. Such climatology was created for continental/marine MCSs and tropical cyclones, including hurricanes. Separate statistics of the “background” vertical profiles and the ones associated with high IWC aloft have been obtained in the course of this study.