Abstract
ABSTRACT:Radar quantitative precipitation estimation plays an important role in weather forecasting, nowcasting and hydrological models. This study evaluates the Sekhon and Srivastava (1970) snow water equivalent (SWE) algorithm currently implemented by the Canadian Radar Network of Environment and Climate Change Canada, suggests an improved algorithm and also evaluates the ability of polarimetric radars in estimating SWE. The radar data were collected from the dual polarimetric King City radar (CWKR) near Toronto, Ontario, and the Doppler Holyrood radar (CWTP) in Newfoundland. SWE data were collected at Oakville, Ontario, at Pearson International Airport (CYYZ), Toronto, Ontario, and at Mount Pearl, Newfoundland. The ground observations show that the polarimetric variables could be used to infer a few of the microphysical processes during snowfall. It is suggested that the co‐polar correlation co‐efficient (ρhv) could be sensitive to the size ranges of different snow habits. Also, higher differential reflectivity (Zdr) values were measured with large aggregates. The results show a severe underestimation of SWE rates by the Sekhon and Srivastava algorithm. One hour accumulations from each site were used to develop SWE(ZeH) and SWE(ZeH, ZDR) algorithms (ZeH and ZDR are the reflectivity factor and differential reflectivity, respectively). Similarly, algorithms were developed using SWE at 10 min intervals from CYYZ and Mount Pearl but these algorithms appeared to overestimate SWE. The hourly SWE accumulations from the three sites were combined to produce an additional SWE(ZeH) algorithm which showed better statistical results. A modest difference was found between the conventional and polarimetric algorithms for estimating snowfall amounts (SWE).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.