Approaches for Compression of Super-Resolution WSR-88D Data

Weather radar products from the U.S. National Weather Service (NWS) are used by the government and private sectors. Very high resolution radar data are increasingly being utilized in real time. However, the bandwidth needed to transmit these data (termed level-II super-resolution data) from the radar to the destination site is a limiting issue. General-purpose compression programs are not tuned to the properties of weather radar data. As the NWS continues to upgrade the capabilities of radar network, the amount of data will continue to increase. As a result, compression is of vital interest to keep down maintenance, storage, and transmission costs. A method for lossless compression of these data on a radial-by-radial basis focusing on the delta (difference) between range bins of super-resolution radar data is presented and is called super-resolution delta compression (SRDC). There are several specialized aspects of SRDC that are based on the properties of weather radar data. SRDC was tested on level-II reflectivity product data from several S-band Doppler weather radars in the NWS network and was compared with two general-purpose compression programs and a different weather-radar-specific compression approach. The results show that the newly developed SRDC yield is approximately 17% better than the next best approach and approximately 47% better than only preprocessed radials.