Evaluation of the dual-polarization weather radar quantitative precipitation estimation using long-term datasets
2021
Abstract. Accurate, timely, and reliable precipitation observations are
mandatory for hydrological forecast and early warning systems. In the case
of convective precipitation, traditional rain gauge networks often miss
precipitation maxima, due to density limitations and the high spatial
variability of the rainfall field. Despite several limitations like attenuation
or partial beam blocking, the use of C-band weather radar has become
operational in most European weather services. Traditionally, weather-radar-based quantitative precipitation estimation (QPE) is derived from
horizontal reflectivity data. Nevertheless, dual-polarization weather radar
can overcome several shortcomings of the conventional horizontal-reflectivity-based estimation. As weather radar archives are growing, they
are becoming increasingly important for climatological purposes in addition
to operational use. For the first time, the present study analyses one of
the longest datasets from fully operational polarimetric C-band weather
radars; these are located in Estonia and Italy, in very different climate
conditions and environments. The length of the datasets used in the study is
5 years for both Estonia and Italy. The study focuses on long-term
observations of summertime precipitation and their quantitative estimations
by polarimetric observations. From such derived QPEs, accumulations for 1 h, 24 h, and 1-month durations are calculated and compared with
reference rain gauges to quantify uncertainties and evaluate performances.
Overall, the radar products showed similar results in Estonia and Italy when
compared to each other. The product where radar reflectivity and specific
differential phase were combined based on a threshold exhibited the best
agreement with gauge values in all accumulation periods. In both countries
reflectivity-based rainfall QPE underestimated and specific differential-phase-based product overestimated gauge measurements.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
44
References
1
Citations
NaN
KQI