Partial blockage is one of the most important error sources of radar observation. A new shielding region identification algorithm without any dependence on the terrain information with high resolution is proposed. The algorithm first computes the probability of every grid's probability of emerging specified reflectivity exceeding a threshold which is defined as Z threshold only through checking the continuous operational radar observation data without using any sample database established manually, and then selects adequate probability threshold which is defined as C threshold to delineate the region with different shielding characters. Applying the algorithm with the continuous operational observation dataset during the period between May and October in 2012 at Jinahua Quhou and Shangrao, the completely shielding region, partially shielding region and no shielding region on 3 km CAPPI are derived separately. With the comparison of the observation data at April 29 in 2013 in the overlapping region on the 3 km CAPPI between Jinhua, Quzhou, Shangrao, Hangzhou and Huangshan, the validation of the identification results of the three radar sites are tested and the parameter sensibility of the Z and C threshold is analyzed, too. The multi-radar mosaic algorithm is optimized applying the partial shielding region results of the radar sites above to enhance the quality of multi-mosaic. The results show that the shielding region with different characters can be identified effectively by selecting adequate Z and C threshold; the selection of the Z and C threshold is the key and moderate Z threshold is beneficial to the further selection of the C threshold; the partial shielding effects can be easily eliminated based on the identification results and the data quality of multi-radar mosaic can be enhanced effectively based on the optimized multi-radar mosaic algorithm.
GOU Yabin
,
LIU Liping
,
LI Ruiyi
,
DU Muyun
,
DUAN Yiping
. Radar Partial Shielding Region Identification Algorithm Based on the Probability Characteristics of Radar Echoes[J]. Plateau Meteorology, 2015
, 34(2)
: 556
-567
.
DOI: 10.7522/j.issn.1000-0534.2013.00192
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