An Investigation of Convective Boundary Layer Depth and Entrainment Zone Properties Using Dual-Pol Radar Observations
Open Access
Author:
Stouffer, Braedon
Graduate Program:
Meteorology and Atmospheric Science
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 26, 2023
Committee Members:
Paul Markowski, Program Head/Chair David Jonathan Stensrud, Thesis Advisor/Co-Advisor Yunji Zhang, Committee Member Matthew Robert Kumjian, Thesis Advisor/Co-Advisor
Properties of the convective boundary layer (CBL) influence a wide variety of meteorological phenomena from air pollutant concentration to thunderstorm initiation. Expanding on previous work done by Banghoff et al. (2018), we show that differential reflectivity (ZDR) observations from National Weather Service dual-polarization Doppler weather radars (WSR-88Ds) can provide accurate estimates of both CBL and entrainment zone (EZ) depth across all stages of CBL development. We combine ZDR and azimuthal ZDR variance into one variable, D-Var, which allows for improved signal identification using the quasi-vertical profile (QVP) method. We find that the centers and vertical extents of channels of reduced D-Var in QVPs correlate well with sounding-observed CBL and EZ depths, respectively. QVP channel width is also found to be closely tied to overall EZ structure. Additionally, we compare observed EZ depths to various EZ parameterizations and show that the parameterizations generally underestimate EZ depth.
