Cooperative Institute for Mesoscale Meteorological Studies

RESEARCH

 

NOAA Strategic Goal 3: Serve Society’s Need for Weather and Water Information

Doppler Weather Radar Research and Development

ROC Project 13 – Analysis of Weather Radar Observations of Severe Convection to Understand Severe Storm Processes and Improve Warning Decision Support

CIMMS students at ROC – Dunn, Bey, Jones, McCarroll, Ong, Setzer, Keel, Patchin, Tantillo; Reed, Haden, Lee, R. Murnan, Steadham, Zittel

Funding Type: CIMMS Task II

Objectives
Develop a data compression technique for the WSR-88D; improve Doppler radar reliability; ensure meteorologists and engineers at ROC have the tools they need for research and development; perform ongoing assessments of WSR-88D data quality; evaluate algorithm performance; verify algorithm performance changes; assist with technology transfer tasks; obtain and analyze special radar data.

Accomplishments
Below is a summary of the activities of CIMMS students at the Radar Operations Center:

Initial research has been conducted on the data compression technique. A transmitter reliability modification has been developed, tested and deployed, and an encoder test set has been developed and updated. An image was developed for ROC computers and deployed on all applicable systems.

CIMMS student employees provide important assistance for the WSR-88D Data Quality Working Group and the ROC Applications Branch. Furthermore, an urgent branch project to evaluate recombination techniques from Super Resolution data required aggressive assistance from all of our CIMMS students.

Specifically, work was done to evaluate radar algorithm performance by reviewing products for defects, errors, and artifacts caused by poor data quality. The performance of a software change for the Mesocyclone Detection Algorithm (MDA) was analyzed and verified from numerous cases. The MDA will replace the legacy Mesocyclone (MESO) algorithm; however, because MDA feature identification criteria are far more lenient than the MESO, tests of adjustments to code were required in order to confirm no adverse operational impacts. In a branch activity to transfer dual polarization research software code into Algorithm Enunciation Language, code logic was organized and specified. Tasks involving recombination techniques included algorithm performance comparisons of the Vertically Integrated Liquid (VIL), the Digital VIL, and the Velocity Wind Profile (VWP) outputs.

One student (Sophia Tantillo) participated in the Oklahoma NASA Space Grant Geospatial Extension Program from 16-25 May. This geospatial extension activity enhanced our general awareness and understanding of geospatial information technology and revealed ways to transfer the technology to endusers.

Work was done on preparations to test lower elevation angles for several potential field sites. Weather for beam overshoot problems was monitored and, accordingly, Level II data were collected in order to establish baseline test information. Involvement with recombination included playback and analysis of the Storm Total Precipitation products as well as correlations of base moments. Histograms and other graphs were prepared using Excel to depict statistics.

Data playback, execution of special test software, and chart and graph preparation in Excel was done in support of a project to improve radial velocity values. The purpose of the project was to validate the reduction in range folding afforded by combining a special signal processing technique with the Multiple Pulse Repetition Frequency Dealiasing Algorithm (MPDA). Adaptable parameters of the MPDA were tested in an attempt to block out noisy data rings near the end of first trip and the start of second trip echo. Level II data sets were catalogued and algorithm performance was evaluated as part of general evaluation efforts in the Data Quality Working Group. Assessments related to deployment of the MDA were conducted. Recombination tasks included algorithm performance comparisons for the Echo Tops (ET), Enhanced Echo Tops (EET), VIL, DVL, MDA, and the Tornado Vortex Signature (TVS) algorithms.

Many of these projects are ongoing.

The ROC mission is to keep the NEXRAD network running at peak performance

Radar Operations Center Mission.