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1 Climatology of Tropical Cyclone Rainfall Over CLIMATOLOGY OF TROPICAL CYCLONE RAINFALL OVER PUERTO RICO: PROCESSES, PATTERNS AND IMPACTS By JOSÉ JAVIER HERNÁNDEZ AYALA A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2016 1 © 2016 José Javier Hernández Ayala 2 To my beloved Puerto Rico, its atmosphere, environment and people 3 ACKNOWLEDGMENTS The main ideas behind the development of this dissertation came from multiple experiences with tropical cyclones while living in Puerto Rico. Those life experiences motivated me to explore the climate of the tropics, with special attention to the rainfall associated with those extreme events and their role in Puerto Rico’s physical geography. The research conducted in this dissertation was possible from support of Dr. Corene Matyas, Associate Professor and Graduate Coordinator at the Department of Geography at the University of Florida. Her magnificent mentoring and continuous support enable me to invest the necessary effort and time to complete this dissertation. I am truly grateful for her exceptional role as my committee chair. I want to thank Dr. Peter Waylen for his continuous support and all of the inspiring conversations we’ve had about research and life in general that gave me even more strength to continue in this journey towards the PhD. I thank Dr. Timothy Fik for sharing his expertise in quantitative methods through two great courses and for inspiring me to aspire to more in life. Thanks to Dr. Zhong-Ren Peng for being my external committee member and teaching me more about the human dimension of climate related phenomena. I am truly grateful to Dr. Michael Binford, Desiree Price and Rhonda Black for their support in departmental procedures. I want to thank Dr. David Keellings for his expertise, support and mentoring in developing the methods section of Chapter 4. I want to thank my family for all of their support during this process, specially my mother Sandra Ayala for always believing in all of my capabilities and encouraging me to dream big. At last, I truly want to thank my wife Katiria Quiles for her continuous emotional support throughout this entire process 4 and for always maintaining a positive attitude towards life that has given me the energy to finish the dissertation and move on to our next dreams in life. 5 TABLE OF CONTENTS Page ACKNOWLEDGMENTS .................................................................................................. 4 LIST OF TABLES ............................................................................................................ 8 LIST OF FIGURES .......................................................................................................... 9 ABSTRACT ................................................................................................................... 11 CHAPTER 1 INTRODUCTION .................................................................................................... 13 Tropical Cyclones, Rainfall and the Case of Puerto Rico........................................ 13 Processes: Tropical Cyclone Rainfall over Puerto Rico and its Relations to Environmental and Storm Specific Factors ......................................................... 15 Patterns: Spatial Distribution of Tropical Cyclone Rainfall and its Contribution to the Climatology of Puerto Rico ................................................................................. 16 Impacts: Extreme Floods and their Relationship with Tropical Cyclones in Puerto Rico .................................................................................................................... 17 Importance of Study ................................................................................................ 18 2 TROPICAL CYCLONE RAINFALL OVER PUERTO RICO AND ITS RELATIONS TO ENVIRONMENTAL AND STORM SPECIFIC FACTORS ................................ 20 Factors Influencing TC Rainfall ............................................................................... 22 Data and Variable Construction .............................................................................. 25 Methods .................................................................................................................. 28 Results and Discussion........................................................................................... 30 Tropical Cyclone Characteristics ...................................................................... 30 Correlation Analyses ........................................................................................ 33 Principal Component Regression ..................................................................... 36 Concluding Remarks............................................................................................... 38 Chapter 2 Limitations .............................................................................................. 40 3 SPATIAL DISTRIBUTION OF TROPICAL CYCLONE RAINFALL AND ITS CONTRIBUTION TO THE CLIMATOLOGY OF PUERTO RICO ........................... 53 Data ........................................................................................................................ 58 Geo-statistical Methods .......................................................................................... 61 Results and Discussion........................................................................................... 64 Characteristics of TC Groups ........................................................................... 64 Spatial Distribution of TCR ............................................................................... 65 TCR Contribution .............................................................................................. 70 6 Concluding Remarks............................................................................................... 72 Chapter 3 Limitations .............................................................................................. 74 4 EXTREME FLOODS AND THEIR RELATIONSHIP WITH TROPICAL CYCLONES IN PUERTO RICO .................................................................................................. 84 Data and Methods .................................................................................................. 87 Floods and Tropical Cyclone Data ................................................................... 87 Extreme Value Analysis Point Process Approach ............................................ 89 Results .................................................................................................................... 91 Descriptive Statistics ........................................................................................ 91 EVA Point Process Model Results ................................................................... 93 Concluding Remarks............................................................................................. 102 Chapter 4 Limitations ............................................................................................ 105 5 CONCLUSION ..................................................................................................... 117 Tropical cyclone Rainfall over Puerto Rico and its Relations to Environmental and Storm Specific Factors ..................................................................................... 117 Spatial Distribution of Tropical Cyclone Rainfall and tts Contribution to the Climatology of Puerto Rico ............................................................................... 119 Extreme Floods and their Relationship with Tropical Cyclones in Puerto Rico ..... 122 Dissertation Contributions ..................................................................................... 124 Future Directions .................................................................................................. 126 LIST OF REFERENCES ............................................................................................. 128 BIOGRAPHICAL SKETCH .......................................................................................... 138 7 LIST OF TABLES Table page 2-1 Storm specific characteristics and environmental factor variables used in this study. ................................................................................................................. 41 2-2 Descriptive statistics of storm specific and environmental factors associated with the 86 TCs analyzed. ........................................................................................ 42 2-3 Tropical cyclones that produced more than 50 mm rainfall over the island of Puerto Rico. ...................................................................................................... 44 2-4 Spearman’s correlation coefficients for each of the predictor’s relationship with mean and maximum TCR. ................................................................................ 46 2-5 Spearman’s correlation coefficients of variables that were found to be significantly correlated with mean and maximum TCR...................................... 47 2-6 Varimax rotated principal component analysis (PCA) results. Data includes the number of components its % of variance. ......................................................... 48 2-7 Forward principal component regression model results for mean and maximum TCR. .................................................................................................................
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