Breakout Summary Report
ARM/ASR User and PI Meeting
2 - 6 May 2016
Radar data products for process studies and modeling applications
4 May 2016
1:30 PM - 3:30 PM
0
Michael Jensen, Pavlos Kollias
4 May 2016
1:30 PM - 3:30 PM
0
Michael Jensen, Pavlos Kollias
Breakout Description
The purpose of this session was to discuss priorities and needs for radar data products with a focus on process studies and modeling applications. The session consisted of four 10-minute talks by the discussion leads, each followed by 20 minutes of discussion on four key areas of radar measurements:1) Scanning ARM Cloud Radar (SACR) products – Beyond SACRCORR,
2) Radar Doppler Spectra products – Next steps for MicroARSCL,
3) Convective Velocity products and
4) Polarimetric Radar products – DSDs and Hydrometeor Classification.
Main Discussion
(1) Scanning ARM Cloud Radar products – Katia Lamer (PSU) presented the current SACRCORR VAP, which separates radar scans, isolates hydrometeors from noise, and corrects for gaseous attenuation and velocity aliasing. The resulting corrected moments are presented in time-elevation coordinates. Some of the next steps include methods for gridding the SACRCORR data, applying a VAD technique for producing horizontal wind profiles, producing domain best-estimate cloud field characteristics (cloud fraction profile, cloud dimensions), and the development of joint grid dual-wavelength radar observables (e.g., DWR) to facilitate the development of advance radar products. The discussion focused on which of these would be most useful to researchers, and which algorithms were ready for operational application.(2) Radar Doppler Spectra products – Ed Luke (BNL) presented a summary of the current MicroARSCL data product, which summarizes features of individual radar Doppler spectra. He proposed the addition of several new variables to a next-generation MicroARSCL product that included:(a) vertical air velocity in layered clouds, (b) reflectivity-weighted particle size distribution sedimentation velocity, (c) eddy dissipation rate in layered clouds and (d) super-cooled liquid mask. The discussion focused on the utility of these additional variables to observationalists and modelers.
(3) Convective Velocity products -Scott Giangrande (BNL) presented a summary of current measurement techniques for convective vertical velocity observations including: (a) aircraft, (b) mult-Doppler radar network and (c) vertically pointing radar. Some of these measurements are focused on a few case studies (aircraft, multi-Doppler) while others are more statistical in nature (Radar Wind Profilers). The discussion focused on the need for both case study retrievals/measurements and statistical representation.
(4) Polarimetric Radar products – V. Chandrasekar (CSU) summarized some of the measurement and retrieval capabilities of scanning polarimetric radars including rainfall rates and hydrometeor classification. The discussion focused on the need for observationalists and modelers working in tandem in order to tailor retrieval output for specific applications.
Issues
Resource requirements for new product development will always be an issue making discussions like the ones held in this breakout an important component of prioritization decisions. The discussions in this breakout identified several candidates for high-priority radar product needs. More importantly, the discussions also identified products that could be contributed by PIs in the near future (e.g., RWP-derived convective vertical velocities), some products that would be useful but not highest priority (e.g., extended MicroARSCL) and some products that should not be pursued operationally with current effort (e.g., hydrometeor classification).Needs
(1) For scanning cloud radar products, gridded fields and domain best-estimate cloud field characteristics were viewed as the most useful extensions of SACRCORR that were also ready for product development. (2) The addition of new variables in the MicroARSCL product was of interest to several attendees, but more focus was on extending the current MicroARSCL data product to more sites/times. (3) Both case study and statistical retrievals of convective vertical velocity are need to be produced and easily available. (4) Collaborations between polarimetric radar experts and modelers may prove more useful than producing a generic hydrometeor classification product.Future Plans
(1) Pursue gridded SACR moments and the objective determination of domain-average cloud field characteristics (coordination with LASSO and ENA site science team).(2) Add additional variables to MicroARSCL output.
Action Items
(1) Process long-term baseline MicroARSCL product at all sites, for all times as soon as the data are available at the ARM DMF.(2) Release PI products (Giangrande) of convective vertical velocity derived from Radar Wind Profilers for MC3E and GoAmazon.