On the Spatial and Temporal Variability of Upwelling in the Southern
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University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 1-1-2012 On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita) Digna Tibisay Rueda-Roa University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the American Studies Commons, Oceanography Commons, Other Earth Sciences Commons, and the Other Oceanography and Atmospheric Sciences and Meteorology Commons Scholar Commons Citation Rueda-Roa, Digna Tibisay, "On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita)" (2012). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/4217 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita) by Digna T. Rueda-Roa A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy College of Marine Science University of South Florida Major Professor: Frank E. Muller-Karger, Ph.D. Mark Luther, Ph.D. Ernst Peebles, Ph.D. David Hollander, Ph.D. Eduardo Klein, Ph.D. Jeremy Mendoza, Ph.D. Date of Approval: June 18, 2012 Keywords: Ekman Transport, Ekman Pumping, hydroacoustics, CARIACO ocean time series, Subtropical Underwater Copyright © 2012, Digna Rueda-Roa DEDICATION Dedicated to the health of the oceans! With the deep belief that the better we know the oceans, the better we can take care of them I am very touched for the continued and unconditional support that my family has provided throughout my career. I am also deeply indebted for the continuous help and support of my extended family at the Institute for Marine Remote Sensing, especially to Frank Muller-Karger, Laura Lorenzoni, Inia Soto and Enrique Montes with whom I have shared a significant part of my career and personal life since I started my studies and research at USF. To all those especial people in my life I also dedicate this work. ACKNOWLEDGEMENTS This dissertation would not have been possible without the generous opportunity that my advisor, Frank Muller-Karger, gave me to do my research and to work in the CARIACO Ocean Time Series Program. I thank him for all his support, encouragement and continuous feedback. I am grateful to the rest of my committee, Mark Luther, Ernst Peebles, David Hollander, Eduardo Klein and Jeremy Mendoza, for their expertise and assistance. I am also grateful to Tal Ezer for providing important suggestions and Matlab code for satellite wind products. Many Venezuelan colleagues enriched this research. I want to thank especially Ramón Varela, Yrene Astor, Baumar Marín, Luis Trocoli and the rest of the CARIACO team, for their support and suggestions. I am in debt to Alina Achury and José Juan Cárdenas for providing and explaining the hydroacoustics sardine biomass data; José Alió and Jeremy Mendoza provided guidance, information, and feedback about the sardine fisheries in Venezuela. The enthusiasm and hard work of Xiomara Gutierrez (Instituto Socialista de Pesca y Acuicultura) to locate and provide Spanish sardine capture data is greatly appreciated. I am grateful to the USF College of Marine Science for the Carl Riggs and the Robert M. Garrels fellowships. This work was funded by various grants to the CARIACO project: NSF and NASA, from U.S.A., CONICIT and FONACIT, from Venezuela. TABLE OF CONTENTS TABLE OF CONTENTS ..................................................................................................... i LIST OF TABLES ............................................................................................................. iv LIST OF FIGURES .............................................................................................................v GENERAL ABSTRACT ................................................................................................... ix PREAMBLE ........................................................................................................................1 Mid-year upwelling:................................................................................................ 2 Contrasting the eastern and western upwelling areas: ............................................ 3 Upwelling cycle influence on the Spanish sardine spatial distribution .................. 3 Scientific manuscripts ............................................................................................. 4 CHAPTER ONE ..................................................................................................................6 Contribution of Ekman transport and pumping on the mid-year southern Caribbean Sea upwelling and on phytoplankton biomass .............................................6 1.1 Abstract ............................................................................................................. 6 1.2 Introduction ....................................................................................................... 7 1.3 Methods........................................................................................................... 10 1.3.1 Temperature ..................................................................................... 10 1.3.2 Wind ................................................................................................. 12 1.3.3 Chlorophyll-a ................................................................................... 13 1.3.4 Sea Level .......................................................................................... 15 1.4 Results and Discussion ................................................................................... 15 1.4.1 Persistence and extension of the mid-year upwelling: ..................... 15 1.4.2 Regional Wind speed and wind-curl patterns: ................................. 19 1.4.3 Forcing mechanisms acting along the coast..................................... 26 1.4.4 Effects of the mid-year upwelling on phytoplankton biomass: ....... 31 1.5 Conclusions ..................................................................................................... 39 1.6 Acknowledgements ......................................................................................... 42 1.7 References ....................................................................................................... 42 CHAPTER TWO ...............................................................................................................49 Southern Caribbean Upwelling System: characterization of sea surface temperature, Ekman forcing and chlorophyll concentration. .......................................49 2.1 Abstract ........................................................................................................... 49 2.2 Introduction ..................................................................................................... 50 2.3 Methods........................................................................................................... 52 i 2.3.1 Sea Surface Temperature ................................................................. 52 2.3.2 Chlorophyll-a ................................................................................... 53 2.3.3 Wind ................................................................................................. 54 2.4 Results and Discussion ................................................................................... 56 2.4.1 Upwelling foci of the southern Caribbean Sea: ............................... 56 2.4.2 Chlorophyll cycle: ............................................................................ 65 2.4.3 Forcing mechanisms along the coast ............................................... 68 2.4.4 Phytoplankton response to the differences in upwelling regimes along the southern Caribbean Sea ......................................... 77 2.5 Conclusions ..................................................................................................... 81 2.6 Acknowledgements ......................................................................................... 84 2.7. References ...................................................................................................... 84 2.8 Appendices ...................................................................................................... 89 Appendix A ............................................................................................... 89 Appendix B ............................................................................................... 90 Appendix C ............................................................................................... 91 CHAPTER THREE ...........................................................................................................92 Spatial variability of Spanish sardine (Sardinella aurita) abundance as related to the upwelling cycle of the southeastern Caribbean Sea ...............................................92 3.1 Abstract ..........................................................................................................