Doppler Weather Radar Research and Development
NSSL Project 7 – Investigation of Advancements in Radar Technology toward the Improvement of Hazardous Weather Detection and Warnings:
Super Resolution Radar Data
Funding Type: CIMMS Task II
Objectives
Increase the detection range of mesocyclone and tornado vortex signatures;
increase the visibility of the reflectivity signatures with super-resolution
data; increase warning times for severe thunderstorms and tornadoes;
and improve radar detection of severe weather, flash floods, and winter
storms.
Accomplishments
Legacy-resolution base data on the NEXRAD network consists of reflectivity
on a 1 km by 1 deg polar grid and Doppler velocity and spectrum width
on a similar 250 m by 1 deg grid. It has been shown that some meteorological
signatures can be detected at greater ranges using radar data with
finer spatial resolution on a 250 m by 0.5 deg grid. Radar data produced
this way is termed super-resolution data. Super-resolution radar data
has the potential to increase the detection range of mesocyclone and
tornado vortex signatures as well as increase the visibility of reflectivity
signatures associated with severe weather. These can contribute toward
an increase in warning times for severe thunderstorms and tornadoes.
This year we completed the development of a super-resolution radial recombination algorithm. This algorithm is fundamental for this project because it allows legacy-like resolution data to be fed to ORPG algorithms when operating in the super-resolution mode. The recommended super-resolution radial recombination algorithm was transferred to the ROC for operational implementation. This implementation was carefully validated with our prototype to ensure the operational version of the algorithm performed as designed.
In close cooperation with the ROC Applications Branch, we began analyzing the effects of feeding recombined base data to the ORPG algorithms. We employed an off-line ORDA playback system to process numerous hours of time-series data. By statistically comparing base data moments obtained from processing the same data sets using the legacy and super-resolution modes of operation, we assessed the effectiveness of the radial recombination algorithm.
This project is ongoing.
Publications
Torres, S. M., and C. D. Curtis, 2006: Design considerations for improved
tornado detection using super-resolution data on the NEXRAD network.
Preprints, Third European Conf. on Radar Meteorology
and Hydrology (ERAD),
Barcelona, Spain.
Reflectivity field from time-series data collected on 23 September 2006 with the KOUN radar. Time-series data were processed using legacy resolution (top left panel) and super-resolution with radial recombination (top right panel). Fields were compared to assess the performance of the radial recombination algorithm. Difference fields (bottom left panel) and histograms (bottom right panel) were produced for all the base data moments.