Automated Cleaning of Doppler Spectra Collected by UMass FMCW during VORTEX-Southeast 2016

During the 2016 VORTEX-Southeast field campaign, which focused on tornado research, the University of Massachusetts S-band Frequency-Modulated Continuous Wave (FMCW) radar was deployed to monitor the growth of the convective boundary layer over northern Alabama. While this radar collected six weeks’ worth of continuous data, the Doppler spectra contain power spurs from the traveling wave tube amplifier. This results in undesirable streaks in the derived reflectivity and Doppler velocity fields that have hindered further analysis of these data.

In this presentation, we demonstrate the removal of these power spurs using the in-painting technique of Chan et al. (2016), showing Doppler spectra before and after the power spurs are removed. The cleaned Doppler spectra will allow a cleaner set of vertical reflectivity and Doppler velocity profiles to be produced for the 6-week observation period. This cleaned data will be submitted to the NCAR-EOL VORTEX-Southeast data archive, which is available to the public, as a new version. The cleaned data will enable automated boundary layer identification and hydrometeor classification algorithms to be applied.