Discussion about the Determination Methods of Weighted Centroid of dBZ on Vector Radar Echoes

Accurate calculation of weighted centroid of dBZ (dBZ stands for decibels of reflectivity of a radar signal reflected off a remote object.) is the basis of studying characteristic tracking algorithms on the vector echoes. The authors mainly discussed the calculation methods of weighted centroid of dBZ on vector echo data. Based on the calculation method on raster echo data, some calculation methods of weighted centroid of dBZ on vector echo data were proposed by considering the weights of features’ area and distance from their location to radar center. And then, taking the base reflectivity products of CINRAD/SA weather radar in Meizhou city of China as data sources, the authors transformed this type of echo data into the vector format. In the end, using the vector echo maps above, the weighted centroid of the same area was calculated by the methods above. Comparing the results with the value of the same area on raster echo maps, the calculated results and the sources of error were analyzed and one conclusion was drawn: it is more accurate to take the features’ area and distance to radar center as weights during the calculation of weighted centroid of dBZ on vector echo maps.