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2016 Waugh Sean Michael Di UNIVERSITY OF OKLAHOMA GRADUATE COLLEGE A BALLOON-BORNE PARTICLE SIZE, IMAGING, AND VELOCITY PROBE FOR IN SITU MICROPHYSICAL MEASUREMENTS A DISSERTATION SUBMITTED TO THE GRADUATE FACULTY in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY By SEAN MICHAEL WAUGH Norman, Oklahoma 2016 A BALLOON-BORNE PARTICLE SIZE, IMAGING, AND VELOCITY PROBE FOR IN SITU MICROPHYSICAL MEASUREMENTS A DISSERTATION APPROVED FOR THE SCHOOL OF METEOROLOGY BY ______________________________ Dr. Michael Biggerstaff, Chair ______________________________ Dr. Kirsten de Beurs ______________________________ Dr. Donald MacGorman ______________________________ Dr. Susan Postawko ______________________________ Dr. Guifu Zhang ______________________________ Dr. Conrad Ziegler © Copyright by SEAN MICHAEL WAUGH 2016 All Rights Reserved. Acknowledgements The author would like to take this opportunity to thank Dr. Erik Rasmussen for his involvement and council in this project. While Dr. Rasmussen wrote the core processing code that was used for the data collected, his involvement went so much further than that. Without his patience and assistance in identifying, debugging, and correcting several changes to the core code, the processing steps would not be where they are today. I owe you a great deal more than simple gratitude and an acknowledgement can convey. I would also like to thank the multitude of students that have helped out with balloon launches over the years. There are too many to name, but their participation, often times at odd hours in less than ideal conditions, is what makes projects like this possible. Without their involvement, launching an instrument of this caliber would be nothing more than a pipe dream. Dr Kim Elmore, your contribution to this work is also invaluable. Not only did you save me a tremendous amount of stress, you helped me to dig into the statistical importance of several aspects of my analysis and demonstrate how robust my results truly are. This work will be a huge step going forward and you have helped me to solidify the ground work. I cannot thank you enough. Finally I would like to thank my committee. The guidance and wisdom that you have all conveyed along the way is what makes this process so rewarding. The experience that I have gained throughout this endeavor will serve me for years to come. I appreciate the patience and understanding that you gave me as I worked through this research. iv Support for this research was provided by NSF grants AGS 10145102 and AGS- 1063945 and by the National Severe Storms Laboratory (NSSL), the latter including federal funding for Rasmussen Systems LLC to develop the Particle Analyzer program. Funding was also provided by NOAA/Office of Oceanic and Atmospheric Research under NOAA-University of Oklahoma Cooperative Agreement #NA11OAR4320072, U.S. Department of Commerce. v Table of Contents ACKNOWLEDGEMENTS ................................................................................................................... IV TABLE OF CONTENTS ........................................................................................................................ VI LIST OF TABLES ..................................................................................................................................... X LIST OF FIGURES ................................................................................................................................. XI ABSTRACT ......................................................................................................................................... XXV CHAPTER 1 ............................................................................................................................................... 1 INTRODUCTION ...................................................................................................................................... 1 1.1. MOTIVATION ..................................................................................................................................... 1 1.2. PREVIOUS WORK ............................................................................................................................... 3 CHAPTER 2 ............................................................................................................................................. 11 PASIV INSTRUMENT PACKAGE ....................................................................................................... 11 2.1. OVERVIEW ....................................................................................................................................... 11 2.2. DESIGN ............................................................................................................................................ 14 2.2.1. Camera .................................................................................................................................... 15 2.2.2. Parsivel ................................................................................................................................... 18 2.3. OPERATIONAL CONSIDERATIONS ..................................................................................................... 20 CHAPTER 3 ............................................................................................................................................. 23 DATA PROCESSING .............................................................................................................................. 23 3.1. CAMERA .......................................................................................................................................... 23 3.1.1. Particle Analyzer (PA) program in IDL .................................................................................. 24 3.1.2. Overview of the Particle Analyzer algorithm .......................................................................... 27 3.1.3. MTS_PNG algorithm .............................................................................................................. 30 3.1.4. Brightness algorithms ............................................................................................................. 34 vi 3.1.5. Post-processing with Matlab................................................................................................... 36 3.2. PARSIVEL ......................................................................................................................................... 38 3.2.1. Identifying launch ................................................................................................................... 39 3.2.2. Merging with radiosonde data ................................................................................................ 40 CHAPTER 4 ............................................................................................................................................. 42 PARTICLE DATA VALIDATION AND INTEGRATION ................................................................. 42 4.1. SIZING ACCURACY AND CORRECTION .............................................................................................. 42 4.2. DETECTION ACCURACY AND SAMPLING CORRECTION ...................................................................... 45 4.3. COMPUTATION OF THE PARTICLE SIZE COUNT AND PARTICLE SIZE DISTRIBUTION............................ 48 CHAPTER 5 ............................................................................................................................................. 50 COMBINED DATA ANALYSIS ............................................................................................................ 50 5.1. MAIN PROGRAM: PARSIVEL ............................................................................................................. 50 5.2. MAIN PROGRAM: EFM ..................................................................................................................... 51 5.3. MAIN PROGRAM: CAMERA ............................................................................................................... 53 5.3.1. Size correction ........................................................................................................................ 53 5.3.2. Particle distribution filter ....................................................................................................... 54 5.3.3. Particle classification ............................................................................................................. 56 5.3.3.1. Precipitation particle categories ...................................................................................................... 57 5.3.3.2. Random Forest classification method ............................................................................................. 61 5.3.3.3. Classification cleanup ..................................................................................................................... 65 5.3.4. Precipitation concentration, reflectivity, and mixing ratio ..................................................... 69 5.3.4.1. Particle size distribution .................................................................................................................. 69 5.3.4.2. Radar reflectivity ............................................................................................................................. 72 5.3.4.3. Mixing ratio....................................................................................................................................
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