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A Statistical and Synoptic Climatology of Tropical Cyclone

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A Statistical and Synoptic Climatology of Tropical Cyclone A STATISTICAL AND SYNOPTIC CLIMATOLOGY OF TROPICAL CYCLONE TORNADO OUTBREAKS DISSERTATION Presented to the Graduate Council of Texas State University-San Marcos in Partial Fulfillment of the Requirements for the Degree Doctor of PHILOSOPHY by Todd W. Moore, B.S., M.S. San Marcos, Texas May 2013 A STATISTICAL AND SYNOPTIC CLIMATOLOGY OF TROPICAL CYCLONE TORNADO OUTBREAKS Committee Members Approved: Richard W. Dixon, Chair Philip W. Suckling David R. Butler Barry D. Keim Approved: J. Michael Willoughby Dean of the Graduate College COPYRIGHT by Todd W. Moore 2013 FAIR USE AND AUTHOR’S PERMISSION STATEMENT Fair Use This work is protected by the Copyright Laws of the United States (Public Law 94-553, section 107). Consistent with fair use as defined in the Copyright Laws, brief quotations from this material are allowed with proper acknowledgment. Use of this material for financial gain without the author’s express written permission is not allowed. Duplication Permission As the copyright holder of this work I, Todd W. Moore, authorize duplication of this work, in whole or in part, for educational or scholarly purposes only. ACKNOWLEDGEMENTS I would first like to acknowledge my advisor, Dr. Richard W. Dixon, for his guidance, not only with this dissertation project, but throughout graduate school. Second, I would like to thank my committee members, Dr. Philip W. Suckling, Dr. David R. Butler, and Dr. Barry D. Keim, for their guidance and support throughout comprehensive exams and with my dissertation project. I also would like to acknowledge Roger Edwards of the Storm Prediction Center for his provision, quality control, and maintenance of the Tropical Cyclone Tornado database and the principle investigators on the National Centers for Environmental Prediction-North American Regional Reanalysis project, Fedor Mesinger, Geoff DiMego, and Eugenia Kalnay, along with all of their team members and collaborators. Lastly, I would like to acknowledge my wife, Siobhan, for her extraordinary patience and understanding throughout this process. Although it may seem so, it has not gone unnoticed and I truly am thankful to have found someone with such qualities. This manuscript was submitted on 19 December 2012. v TABLE OF CONTENTS Page ACKNOWLEDGEMENTS .................................................................................................v LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES ........................................................................................................... xi ABSTRACT .......................................................................................................................xv CHAPTER I. INTRODUCTION ............................................................................................................1 1.1 Overview ....................................................................................................................1 1.1.1 Dissertation Organization ...................................................................................2 1.2 Research Motivations.................................................................................................3 1.2.1 Tropical Cyclone Tornado Clusters ....................................................................3 1.2.2 Societal Impacts and Anticipation ......................................................................4 1.2.3 Geographic Nature ..............................................................................................8 1.3 Research Goals, Questions, Objectives, and Assumptions ........................................8 1.4 Chapter One Figures ................................................................................................11 II. BACKGROUND AND LITERATURE REVIEW .......................................................13 2.1 Introduction and Background ..................................................................................13 2.1.1 Atmospheric Circulation ...................................................................................13 2.1.2 Tropical Cyclones .............................................................................................15 2.1.3 Tornadoes ..........................................................................................................17 2.2 Tropical Cyclone Tornadoes ....................................................................................19 2.2.1 Definition and Identification .............................................................................19 2.2.2 Climatology.......................................................................................................22 2.2.2.1 General Frequency .....................................................................................23 2.2.2.2 Temporal Distribution ................................................................................23 2.2.2.3 Spatial Distribution ....................................................................................25 2.2.3 Case Studies ......................................................................................................26 2.2.4 Formation, Forecasting, and Detection .............................................................27 2.2.5 General Conclusions from the Literature ..........................................................31 vi 2.3 Synoptic Climatology ..............................................................................................32 2.3.1 Definition ..........................................................................................................32 2.3.2 Historical Developments ...................................................................................33 2.3.3 Approaches and Methods ..................................................................................36 2.4 Synoptic Climatology of Tropical Cyclone Tornadoes ...........................................39 2.5 Concluding Remarks ................................................................................................43 2.6 Chapter Two Figures................................................................................................46 III. DATA AND METHODS ............................................................................................49 3.1 Data ..........................................................................................................................49 3.1.1 Tropical Cyclone Tornado Data........................................................................49 3.1.2 Synoptic Data ....................................................................................................50 3.2 Methods....................................................................................................................55 3.2.1 Tropical Cyclone Tornado Outbreaks: Definition and Identification ...............56 3.2.2 Synoptic Classification Process ........................................................................59 3.2.2.1 Classification Goals ...................................................................................59 3.2.2.2 Classification Process ................................................................................60 3.2.2.3 Tropical Cyclone-Westerly Interaction Patterns ........................................63 3.2.2.4 No Tropical Cyclone-Westerly Interaction Patterns ..................................65 3.2.3 Statistical Analysis ............................................................................................65 3.3 Chapter Three Tables ...............................................................................................73 3.4 Chapter Three Figures..............................................................................................78 IV. RESULTS ....................................................................................................................83 4.1 Statistical Description of Tropical Cyclone Tornado Outbreaks .............................84 4.1.1 Frequency and Severity.....................................................................................84 4.1.2 Temporal Characteristics ..................................................................................85 4.1.3 Spatial Characteristics .......................................................................................87 4.2 Synoptic Patterns Associated with Tropical Cyclone Tornado Outbreaks ..............88 4.2.1 Description and Within-Group Analysis of Synoptic Patterns .........................89 4.2.1.1 Pattern 1 Tropical Cyclone Tornado Outbreaks ........................................89 4.2.1.2 Pattern 2 Tropical Cyclone Tornado Outbreaks ........................................91 4.2.1.3 Pattern 3 Tropical Cyclone Tornado Outbreaks ........................................92 4.2.1.4 Pattern 4 Tropical Cyclone Tornado Outbreaks ........................................94 4.2.1.5 Pattern 5 Tropical Cyclone Tornado Outbreaks ........................................95 4.2.2 Synoptic Pattern Persistence and Variability ....................................................96 4.2.3 Between-Group Analysis of Synoptic Patterns ................................................97 4.2.3.1 Outbreak Frequency ...................................................................................97 4.2.3.2 Outbreak Severity ......................................................................................97 4.2.3.3 Tropical Cyclone Tornado Strength...........................................................99
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