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Quantification of Bird Migration Using Doppler Weather Surveillance Radars A Thesis entitled Quantification of Bird Migration Using Doppler Weather Surveillance Radars (NEXRAD) by Priyadarsini Komatineni Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Electrical Engineering Dr. Mohsin M. Jamali, Committee Chair Dr. Junghwan Kim, Committee Member Dr. Peter V. Gorsevski, Committee Member Dr. Patricia R. Komuniecki, Dean College of Graduate Studies The University of Toledo August 2012 Copyright 2012, Priyadarsini Komatineni This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of Quantification of Bird Migration Using Doppler Weather Surveillance Radars (NEXRAD) by Priyadarsini Komatineni Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Electrical Engineering and Computer Science The University of Toledo August 2012 Wind Energy is an important renewable source in United States. Since past few years, the growth of wind farms construction has significantly increased, due to which there is an increase in number of bird deaths. Therefore, ornithologists began to study the bird’s behavior during different migration periods. So far ornithologists have used many methods to study the bird migration patterns in which the radar ornithology has been used in an innovative way. However, many studies have focused using small portable radars and recently researchers have proved that the migration events can be studied through large broad scale radars like NEXRAD. Throughout the United States, NEXRAD has 160 Doppler Weather Surveillance Radars. The advantage of NEXRAD is that it can provide bird migration movements over a broad geographical scale and can be accessed free of charge. In this thesis, an algorithm has been designed to observe the bird migration patterns in aerosphere using NEXRAD. However, unfortunately, there is some bias in the radar measures due to its operational characteristics. Therefore, the designed algorithm has iii been used to adjust the radar measures using radar beam geometry and increase the efficiency of the results from clutter using image processing techniques. In addition, the algorithm also reduces the computational time. The NEXRAD used in the study is from KCLE station, Brook park, Ohio. The thesis used three study areas which are located towards West and North-West direction from the station KCLE, to observe the bird migration patterns according to the adjusted beam height (AGL). The study area # 1, # 2 and # 3 are located in Ohio at Ottawa National Wildlife Refuge, Sandusky, and Vermilion respectively. At Study area #1, observations from NEXRAD were compared and correlated with independent observations using Marine Radar. The method discussed in this thesis was limited to the radar range up to 80 km. The work will be useful to wildlife biologists, wind farm developers and policy makers. It can be used within 80 km range of any of the NEXRAD in the country. iv Acknowledgements Firstly, I would like to thank the almighty God for making this possible and guiding me through life. I am very grateful to my mother Mrs. Prameela and my father Mr. Ramakrishna Prasad for their love, blessings and supporting all through my life. A very special thanks to my graduate advisor Dr. Mohsin Jamali for his help and guidance without which this would not be possible. My special thanks to Dr. Prof. Verner Bingman of the Department of Psychology at BGSU, Prof. Joseph Frizado from Department of Geology at BGSU, Prof. Peter Gorsevski from the Department of Geospatial Sciences at BGSU and Dr. Jeremy D. Ross for their timely feedback and valuable suggestions. I would like to thank the Department of Energy (Contract #DE- FG36-06G086096). I would like to extend my thanks to Dr. Kim for his time to serve as my committee member. A heartfelt thanks to my friend Nishatha Nagarajan who supported me throughout my thesis work. I would also like to thank my fellow students Mohammad Wadood Majid, Golrokh Mirzaei and Vamshi Gummala for their support. v Table of Contents Abstract .............................................................................................................................. iii Table of Contents .................................................................................................................v List of Tables .................................................................................................................. vii List of Figures .................................................................................................................. viii 1. Introduction……………….. ............................................................................................1 1.1. Preface to Thesis ...............................................................................................4 1.2. Scope………………………………………………………………………….5 1.3. Outline of Thesis..............................................................….............................5 2. Literature Review………………………………………………………………………7 2.1. Factors that influence the Bird Migration……………………………………8 2.2. Techniques used to study Bird Migration…………………………………... 8 3. NEXRAD…………. ......................................................................................................17 3.1. Introduction to NEXRAD ...............................................................................17 3.2. WSR-88D (Weather Surveillance radar) ........................................................19 3.3. Technical Details of WSR-88D……………………………………………..20 3.3.1. Volume Coverage Patterns…………………………………………....23 3.3.2. Modes of Operation…...........................................................................24 3.4. Radar Imagery………………………………………………………………27 vi 3.4.1. Reflectivity……………………………………………………………29 3.4.2. Radial Velocity...……...……………………………………………....30 3.4.3. Spectrum Width...……...……………………………………………...31 3.5. Data Downloading Steps from NOAA………………………………………32 4. Radar Data Processing...…………. ...............................................................................38 4.1. Algorithm………..……………………………………………………...........39 4.2. Description…..…...……...……………………………………………...........41 4.3. Quantification...…………. ..............................................................................48 4.4. Quantifying Bird Density (Buler and Diehl) ………………………………..50 4.4.1. Buler and Diehl Algorithm …………………………………………...50 4.4.2. Proposed Method…...…………………………………………………51 5. Data Analysis....……………………………………………………………………….54 5.1. Study Design ………..…………………………………………………….....59 5.2. Simulation Results …..…................................................................................60 6. Conclusion and Future Work....……………………………………………………….82 References ..........................................................................................................................84 vii List of Tables 3.1 Technical Parameters of NEXRAD ……………………………………………..20 3.2 Comparison between Level II and Level III data………………………………..28 4.1 Comparison between Buler and Diehl and Proposed Algorithm………………...53 5.1 Variation of Bird Density on Land and Water ………………………………….74 5.2 Comparison between NEXRAD and Marine Radar Observations………………80 viii List of Figures 1-1 Interaction of Birds with Wind Turbines .................................................................2 1-2 Bird mortalities due to wind turbines.......................................................................3 3-1 NEXRAD site, Norman. Oklahoma.......................................................................18 3-2 Doppler Weather Radar (WSR-88D) coverage throughout United States ............19 3-3 Functional Components of the NEXRAD System………………………………22 3-4 Example of Volume Coverage Pattern ..................................................................24 3-5 Volume Coverage in Clear Air Mode ....................................................................25 3-6 Volume Coverage in Precipitation Mode ..............................................................26 3-7 Example of Reflectivity Image from NEXRAD Level-II Scan .............................29 3-8 Example of Radial Velocity Image from NEXRAD Level-II Scan ......................30 3-9 Example of Spectrum Width Image from NEXRAD Level-II Scan .....................32 3-10 Flowchart to download NEXRAD data .................................................................33 3-11 Example Image of ordering NEXRAD data .........................................................35 3-12 Example Image of ordering NEXRAD data Inventory Search..............................35 3-13 Example Image of ordered NEXRAD data …......................................................36 3-14 Example Image of ordered NEXRAD data with data selector ..........……………36 3-15 Example of ordered Reflectivity data from Radial Properties dialog box……….37 4-1 NEXRAD Data Processing Algorithm ..................................................................40 4-2 Noise Filtering Techniques ....................................................................................42 ix 4-3 Flow Chart to Reduce Bias ....................................................................................45 4-4 Flowchart of Improved Algorithm……………………………………………….52 5-1 Map of KCLE station located at Glenn Research center, Brook Park ...................55 5-2 Map of Ottawa National Wildlife Refugee and NEXRAD, Brook Park………...56 5-3 Location of Marine Radar……………………………………………………….56
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