NAME: Raindrop Count Data TYPE: Observational Data from Joss-Waldvogel (JW) and Parsivel Disdrometers SIZE: Two Separate Files – JW.txt: 1440 observations, 22 variables; Parsivel.txt: 463 observations, 22 variables DESCRIPTIVE ABSTRACT: Counts of raindrop diameters in contiguous bins are given for one-minute time periods for each of two different diameters. Students at all levels may summarize the data with simple descriptive statistics. Students with an appropriate mathematical statistics background may model raindrop size parametrically using several different density models. Complications in the modelling result from the data being both truncated (not all observations are seen) and binned. SOURCE: The Kwajalein Atoll disdrometer data was kindly provided courtesy of the US Army Space Missile Defense Command Reagan Test Site, NASA Goddard Space Flight Center, and Atmospheric Technology Services Co. The Parsivel disdrometer data was kindly provided courtesy of Dr. Walt Petersen while he was associated with the Earth System Science Center, National Space Science and Technology Center, University of Alabama, Huntsville. DATASET NAME: JW.txt Column & Variable Description 1 Hour of observation (UTC) 2 Minute of observation (UTC) 3 Number of drops in the interval [0.313, 0.405) (all bin measurements in mm) 4 Number of drops in the interval [0.405, 0.505) 5 Number of drops in the interval [0.505, 0.596) 6 Number of drops in the interval [0.596, 0.715) 7 Number of drops in the interval [0.715, 0.827) 8 Number of drops in the interval [0.827, 1.000) 9 Number of drops in the interval [1.000, 1.233) 10 Number of drops in the interval [1.233, 1.430) 11 Number of drops in the interval [1.430, 1.583) 12 Number of drops in the interval [1.583, 1.750) 13 Number of drops in the interval [1.750, 2.079) 14 Number of drops in the interval [2.079, 2.443) 15 Number of drops in the interval [2.433, 2.730) 16 Number of drops in the interval [2.730, 3.014) 17 Number of drops in the interval [3.014, 3.388) 18 Number of drops in the interval [3.388, 3.707) 19 Number of drops in the interval [3.707, 4.130) 20 Number of drops in the interval [4.130, 4.576) 21 Number of drops in the interval [4.576, 5.145) 22 Number of drops in the interval [5.145, 5.600) DATASET NAME: Parsivel.txt Column & Variable Description 1 Hour of observation (UTC) 2 Minute of observation (UTC) 3 Number of drops in the interval [0.250, 0.375) (all bin measurements in mm) 4 Number of drops in the interval [0.375, 0.500) 5 Number of drops in the interval [0.500, 0.625) 6 Number of drops in the interval [0.625, 0.750) 7 Number of drops in the interval [0.750, 0.875) 8 Number of drops in the interval [0.875, 1.000) 9 Number of drops in the interval [1.000, 1.125) 10 Number of drops in the interval [1.125, 1.250) 11 Number of drops in the interval [1.250, 1.500) 12 Number of drops in the interval [1.500, 1.750) 13 Number of drops in the interval [1.750, 2.000) 14 Number of drops in the interval [2.000, 2.250) 15 Number of drops in the interval [2.250, 2.500) 16 Number of drops in the interval [2.500, 3.000) 17 Number of drops in the interval [3.000, 3.500) 18 Number of drops in the interval [3.500, 4.000) 19 Number of drops in the interval [4.000, 4.500) 20 Number of drops in the interval [4.500, 5.000) 21 Number of drops in the interval [5.000, 6.000) 22 Number of drops in the interval [6.000, 7.000) STORY BEHIND THE DATA: JW.txt: 1,440 (24*60) observations from the Kwajalein Atoll in the Marshall Islands 00:00 (hh:mm) through 23:59 UTC on 17 October 2010. While observations were made every minute during the day, no raindrop diameters less than 0.313 mm were observed and no raindrop diameters 5.600 mm or larger were observed. Parsivel.txt: 463 observations from Huntsville Alabama 09:44 (hh:mm) through 19:55 UTC on 8 November 2009. Of the 612 one-minute intervals in this time frame 149 (612-463) are missing. These missing observation times presumably correspond to periods of no or intermittent rain as adjacent observations generally correspond to little rain. No raindrop diameters less than 0.250 mm were observed and no raindrop diameters 7.000 mm or larger were observed. SUBMITTED BY: Roger W. Johnson Department of Mathematics and Computer Science South Dakota School of Mines & Technology Rapid City, SD 57701 roger.johnson@sdsmt.edu Donna V. Kliche Atmospheric and Environmental Sciences Program South Dakota School of Mines & Technology Rapid City, SD 57701 donna.kliche@sdsmt.edu Paul L. Smith Atmospheric and Environmental Sciences Program South Dakota School of Mines & Technology Rapid City, SD 57701 paul.smith@sdsmt.edu