Comparative Analysis of Precipitation Observation During a Hail Process
In order to study the method of measuring precipitation by the DSG5 precipitation weather phenomenon instrument,we compare the detection performance of tipping bucket rain gauge,weighing rain gauge,and the DSG5 precipitation weather phenomenon instrument on precipitation in hail processes.We analyse the characteristics of the precipitation particle spectrum in a hail process.We also discuss the interference of hail on the identification of the DSG5 precipitation weather phenomenon and the method for distinguishing raindrops from hail using raindrop spectrum characteristics.Following this method,we calculate the precipitation formed by raindrops and hail.It is found that hail was easily able to roll into the sampling area from the edge of the DSG5 splash cover or by bouncing on the splash cover,which not only seriously interfered with the judgement of the DSG5 precipitation weather phenomenon but also caused a large error in the precipitation calculated by DSG5.However,the interference particles were generally identified by DSG5 as belonging to the"snow area".Based on the criterion of DSG5 for different precipitation weather phenomena,the particles that were judged to enter the"snow area"were deleted,and the particles in the"rain with snow"area were merged into the"rain area".The hail and raindrops in the hail process could be separated.The amount of precipitation formed separately was calculated according to different densities,and then the total precipitation of hail and raindrops was calculated.The calculation results have certain accuracy.The comparative analysis and statistical test of the minute precipitation series of the hail process calculated by the tipping bucket rain gauge,the weighing rain gauge,and the DSG5 show that the minute precipitation series of the process obtained by the tipping bucket rain gauge,the weighing rain gauge,and the DSG5 had good consistency and obeyed the same continuous distribution.Due to the different structures and principles of the equipment,the minute precipitation series obtained by the three methods were also significantly different.The DSG5 could quickly and sensitively detect the start and end times of precipitation,and more accurately reflect the temporal change of precipitation intensity,which could provide accurate precipitation change information for the study of small-and medium-scale weather systems.The tipping bucket rain gauge and the weighing rain gauge had a certain buffer in observing the minute precipitation during the hail process and could not accurately describe the change in the real-time intensity of the minute precipitation.The minute precipitation sequence observed by the weighing rain gauge exhibited an obvious lag during hail processes.