Inter-comparison of DSDs between Jincheon and Miryang at South Korea

Abstract

This study explores the characteristics of drop size distribution (DSD) using PARticle SIze and VELocity (Parsivel) disdrometer at Jincheon (JC; 36.9 °N, 127.5 °E) and Miryang (MY; 35.5 °N, 128.6 °E) sites, during the period June 2015 to March 2016. Twelve cases were selected from Parsivel disdrometer data to compare the characteristics of DSDs between central and southeastern Korea. The average DSD at both sites shows a similar pattern; there is a slightly larger magnitude of small drops at JC. A comparison was undertaken on average raindrop spectra at JC and MY during three different rainfall systems; namely the Changma (CS), Localized low pressure (LS), and Typhoon (TS) system. Rainfall at JC tends to have more raindrops than MY especially over small diameter drops (0.31−0.81 mm). The differences in JC and MY may be attributed to the errors related to use of the Parsivel disdrometer, differences in the amounts of rainfall, or differences in the prevailing rainfall systems (CS, LS, and TS). Total monthly rainfall at JC and MY were 783.10 (726.92) and 781.80 (701.17) mm, respectively based on the rain gauge and Automatic Weather Stations (AWS). However, there was good agreement (within 7%−11%) between Parsivel disdrometer data and data obtained from the rain gauges or AWS. The average raindrop spectra at JC tends to have more raindrops than MY in different rainfall systems especially over small drops. During CS, the rainfall at JC is higher than MY across all the diameters on July 23, 2015. During LS at both sites there is a similar pattern, but with slightly larger diameter at JC as measured on August 16, 2015 (D> 6.5 mm). The rainfall at JC during TS tends to have more small drops compared to MY on July 12, 2015. The DSD characteristics are different across rainfall systems and climatic regions.