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Drainage of Deep Mediterranean Water, Its Transition Through the Strait of Gibraltar: Spatial and Temporal Variability

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Drainage of Deep Mediterranean Water, Its Transition Through the Strait of Gibraltar: Spatial and Temporal Variability Universidad de Málaga Departamento de Física Aplicada II Escuela Doctoral Internacional en Estudios del Mar (EDEIMAR) Programa de doctorado: Dinámica de los flujos biogeoquímicos y sus aplicaciones. Drainage of deep Mediterranean Water, its transition through the Strait of Gibraltar: spatial and temporal variability. Tesis Doctoral presentada por: Cristina Naranjo Rosa Dirigida por: Jesús García Lafuente Y codirigida por: José Carlos Sánchez Garrido Drainage of deep Mediterranean Water, its transition through the Strait of Gibraltar: spatial and temporal variability (Drenaje de las aguas profun das del mar meditterráneo, estudio de su tránsito a traavés del Estrecho de Gibraltar y su variabilidad espacio-temporal) Tesis Doctoral presentada por: Cristina Naranjo Rosa Dirigida por: Jesús García Lafuente Y codirigida por: José Carlos Sánchez Garrido Para obtener el grado de Doctora por la Universidad de Málaga Departamento de Física Aplicada II Grupo de Oceanografía física Escuela de doctorado: Escuela doctoral internacional en estudios del mar (EIDEMAR) Programa de doctorado: Dinámica de los flujos biogeoquímicos y sus aplicaciiones El Director El Codirector La Doctoranda Jesús García Lafuente José Carloss Sánchez Garrido Cristina Naranjo Rosa D. Jesús García Lafuente, catedrático de la Universidad de Málaga y D. José Carlos Sánchez Garrido, investigador del Departamento de Física Aplicada II de la Universidad de Málaga HACEN CONSTAR: Que el trabajo recogido en la memoria titulada “Drainage of deep Mediterranean Water, its transition through the Strait of Gibraltar: spatial and temporal variability”, presentada por Cristina Naranjo Rosa, ha sido realizado bajo nuestra supervisión y cumple con la calidad científica suficiente. Que la presente tesis está avalada por cuatro artículos, dos de ellos ya publicados, un tercero enviado tras una segunda revisión menor y un último en (moderada‐menor) revisión. Todos ellos en revistas de alto índice de impacto en su área que no han sido presentados anteriormente en ninguna otra tesis. Que reúne sobradamente los criterios de calidad establecidos para la lectura de la tesis en el programa de doctorado “Dinámica de los flujos biogeoquímicos y sus aplicaciones”, por ello se informa muy favorablemente sobre el trabajo realizado y se autoriza su presentación y defensa para optar al grado de Doctor Internacional por la Universidad de Málaga. Para ello firmamos la presente en Málaga a 06 de julio de 2015. Fdo. Director Fdo. Codirector Jesús García Lafuente José Carlos Sánchez Garrido A mis padres, mis hermanos y nuestros dos soles, Adri y Guille TABLE OF CONTENTS I. PUBLICATIONS ARISING FROM THIS THESIS ............................................................. 3 II. GENERAL INTRODUCTION ......................................................................................... 5 II.a. Abstract .............................................................................................................. 5 II.b. State of the art ................................................................................................... 5 II.c. The objectives of this dissertation and its organization .................................. 10 II.d. Methodology .................................................................................................... 11 III. The Western Alboran Gyre helps ventilate the Western Mediterranean Deep Water through Gibraltar ................................................................................................. 13 IV. How much do tides affect the circulation of the Mediterranean Sea? From local processes in the Strait of Gibraltar to basin‐scale effects .............................................. 21 V. Modeling the impact of tidal flows on the biological productivity of the Alboran Sea ................................................................................................................................. 31 VI. Mediterranean waters along and across the Strait of Gibraltar, characterization and zonal modification ................................................................................................... 77 VII. GENERAL DISCUSSION ...................................................................................... 109 VIII MAIN CONCLUSIONS.......................................................................................... 108 IX. RESUMEN EN ESPAÑOL ..................................................................................... 115 IX.a. Breve Resumen ............................................................................................ 115 XI.b. Estado de la cuestión y Metodología .......................................................... 116 IX.c. Resultados más significativos ...................................................................... 121 IX.d. Principales conclusiones de esta memoria ................................................. 127 X. List of Abbreviations............................................................................................. 128 XI. References............................................................................................................ 130 I. Publications Arising from this Thesis I. PUBLICATIONS ARISING FROM THIS THESIS The thesis hereby is presented as a “thesis by published works”. A total of four papers are gathered to this aim, which have been published (a, and b), accepted for publication (c) or under review (d) in scientific journals all of them belonging to the first quartile in the oceanography area. This thesis model has been previously supported by the directors in the corresponding inform. The four papers listed below deal with different aspects of the drainage of deep Mediterranean waters through the Strait of Gibraltar from the Alboran basin to the Atlantic Ocean as well as with the effect that the local tides in the Strait have on larger scale processes taking place in the neighboring basins. a) Cristina Naranjo, Jesús García Lafuente, Jose C. Sánchez Garrido, Antonio Sánchez Román, Javier Delgado Cabello, The Western Alboran Gyre helps ventilate the Western Mediterranean Deep Water through Gibraltar. Deep Sea Research Part I: Oceanographic Research Papers, Volume 63, May 2012, Pages 157‐163, ISSN 0967‐0637, http://dx.doi.org/10.1016/j.dsr.2011.10.003. Impact factor: 2.825 Quartile in category: Q1 b) Cristina Naranjo, Jesús García Lafuente, Gianmaria Sannino, Jose C. Sánchez Garrido, How much do tides affect the circulation of the Mediterranean Sea? From local processes in the Strait of Gibraltar to basin‐scale effects. Progress in Oceanography, Volume 127, September 2014, Pages 108‐116, ISSN 0079‐6611, http://dx.doi.org/10.1016/j.pocean.2014.06.005. Impact factor: 3.986 Quartile in category: Q1 c) Jose C. Sánchez Garrido, Cristina Naranjo, Jesús García Lafuente, Diego Macías, Temel Oguz, Modeling the impact of tidal flows on the biological productivity of the Alboran Sea. Journal of Geophysical Research: Oceans, submitted under a second minor revision. Impact factor: 3.440 Quartile in category: Q1 3 I. Publications Arising from this Thesis d) Cristina Naranjo, Simone Sammartino, Jesús García Lafuente, María J. Bellanco, Isabelle Taupier Letage. Mediterranean waters along and across the Strait of Gibraltar, characterization and zonal modification. Submitted to Deep Sea Research Part I: Oceanographic Research Papers. Under review (a first report from the reviewers has been received; two out of three recommend publication with minor or very minor revision and the third reviewer also recommend the publication but with a more in depth revision. Currently, July 6, 2015 we are working in the new version). Impact factor: 2.825 Quartile in category: Q1 4 II. General Introduction II. GENERAL INTRODUCTION II.a. Abstract This Thesis is the outcome of the research carried out in the Strait of Gibraltar and adjacent basins during the last years in the frame of the INGRES research projects conducted by the Physical Oceanography Group of the University of Málaga. A first objective was the understanding of the ventilation of the deep waters in the Alboran Sea and the identification of the mechanisms and processes involved, such as the role of regional‐scale structures, the tidal forcing in the Strait or the spatio‐temporal pattern of the water masses participating in the exchange through the Strait. These topics provide new insights about the dynamics and properties of the Mediterranean outflow before leaving the Mediterranean Sea. The interesting and relevant issue of the impact of tides in the Strait in the bio‐geochemistry of the Alboran Sea is the last topic addressed in the Thesis1. II.b. State of the art Early questions about the origin of the Mediterranean outflow were investigated by Stommel et al. [1973]. The authors ascribed the uplift of deep Mediterranean water in the Alboran Sea to the Bernoulli suction driven by the high velocities occurring in the main sill of the Strait of Gibraltar, and concluded that even the deepest water in the Mediterranean could flow upward and out through the Strait. These authors measured potential temperature of θ=12.84ºC, which corresponds to the Western Mediterranean Deep Water (WMDW), in the eastern entrance of the Strait. Nevertheless they acknowledged that the θ‐S characteristics of this water would be eroded inside the Strait and that its observation on the Atlantic side of the Strait, beyond the Camarinal sill (CS hereinafter, see Figure 1), would not be an easy task. The mentioned work found also that isotherms are banked
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