A Comparative Study of Rainfall Observations during GPM Iphex Field Campaign

Monday, 15 December 2014
Md Kalimur Rahman, Clemson University, Glenn Department of Civil Engineering, Clemson, SC, United States, Ali Tokay, NASA, Greenbelt, MD, United States and Firat Y. Testik, Clemson Univ., Clemson, SC, United States
Measurement capabilities of a new optical disdrometer called High-speed Optical Disdrometer (HOD) were evaluated through a comparative study with the 2-Dimensional Video Disdrometer (2DVD), and the Pluvio200 weighing bucket rain gauge. All instruments were collocated at the Maggie Valley site of the Integrated Precipitation Hydrology Experiment (IPHEx) field campaign. This field campaign was a joint effort between NASA’s Global Precipitation Measurement (GPM) ground validation program, Duke University, and NOAA’s Hydrometeorology Testbed – South East. Collocated measurements were conducted for three rain events during May 10-15, 2014. Among these events, one of them was a heavy rain event (conditional mean rain rate of 18.7 mm h-1) and the other two were light rain events (conditional rain rates of 2.5 and 2.7 mm h-1). This comparative study seeks the degree of agreement among precipitation measuring instruments for the rain total, raindrop size distribution, and fall velocity. Findings of these comparisons along with the microphysical observations by the HOD and the 2DVD will be presented.