Paper: | TP-L4.5 |
Session: | Geosciences and Remote Sensing I |
Time: | Tuesday, September 18, 16:10 - 16:30 |
Presentation: |
Lecture
|
Title: |
POLARIMETRIC AZIMUTHAL SPECTRAL HISTOGRAM EXPOSES TYPES OF MIXED SCATTERERS AND THE CAUSE FOR UNEXPECTED POLARIMETRIC AVERAGES |
Authors: |
Svetlana Bachmann; Cooperative Institute for Mesoscale Meteorological Studies | | |
| Dusan Zrnic; National Severe Storm Laboratory | | |
| Victor DeBrunner; Florida State University | | |
Abstract: |
Echoes detected by polarimetric weather radar in clear air contain signals from air and biological scatterers. Discriminating scatterer types from a composite echo is challenging due to variability in scatterers’ quantity, azimuthal dependences of their polarimetric properties, and uneven mixing in resolution volumes. We use polarimetric spectral densities to estimate volume’s content by constructing two dimensional (2D) histograms in Doppler velocity – polarimetric variable space. Assimilation of these histograms in azimuth results in a 3D azimuthal spectral histogram (3DASH). We use transparency for small occurrences to visualize 3D signatures of the dominant content. The scatterer types have distinguishable signatures in the 3DASH due to their diverse physical shapes, scattering properties, different headings, and speeds. The 3DASH helps understand averages over the resolution volume. Further in the 3DASH one can identify intrinsic polarimetric values/functions for different types of biological scatterers, which are necessary for scatterer classification algorithms. |