Assessing the Rain Estimate from the Feflectivity of Nha Be Radar

Abstract

Abstract: This study evaluates the estimated rainfall from Nha Be radar observation using different experimental formulas. The results show that in six estimation formulas used, the formulation of Joss' large-scale rainfall estimation and Marshall-Plamer's formulation can be used to estimate precipitation for the southwest monsoon with an error of approximately 5 mm/h and usually smaller than the observed value. The rainfall estimation formula by Nguyen Huong Dien is the optimum estimation for the 9 synoptic rainfall patterns: Intertropical Convergence Zone, Southwest monsoon associated with Intertropical Convergence Zone, low-pressure area, thunderstorm, disturbance in East winds, low-pressure area associated with Southwest monsoon, low-pressure troughs have a Northwestern-Southeasterly direction and other synoptic patterns with errors: 5mm/h, 9.5 mm/h, 14 mm/h, 7mm/h, 19 mm/h, 8 mm/h, 8.5 mm/h, 9.5 mm/h and 14.7 mm/h, respectively.

Keywords:  Radar, rain estimate.

References:

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