Modeling the marine silicon cycle [Elektronische Ressource] : physics, chemistry, and biology / vorgelegt von André Gerhard Wischmeyer

Modeling the Marine Silicon Cycle—Physics, Chemistry, and BiologyDissertationzurErlangung des Grades einesDoktors der Naturwissenschaften- Dr. rer. nat. -Dem Fachbereich Physik derUniversit¨ at Bremenvorgelegt vonAndr´e Gerhard WischmeyerBremen, 30. Oktober, 20021. Gutachter: Prof. Dr. D. Wolf-Gladrow2. Gutachter: Prof. Dr. P. Lemke¨Alfred-Wegener-Institut fur Polar- und MeeresforschungContentsIntroduction 11 Theoretical Constraints on the Uptake of Silicic Acid by Marine Diatoms 51.1 Diffusion-ReactionEquations .......................... 61.2 RateConstantsandDiffusionCoefficients ................... 81.3 ReferenceRuns.................................. 101.4 Analytical Solutions and Reacto-Diffusive Length Scales . . . . . . . . . . . 121.5 Results....................................... 161.6 Discusion..................................... 202 The Cycle of Silicic Acid in the Equatorial Pacific 232.1 A Model for the Pacific Ocean Silicon Cycle . . . . . . . . . . . . . . . . . . 242.2 Model Results: Climatology, El Nino˜ and La Nina˜ in the Equatorial Pacific . 262.2.1 Climatology................................ 272.2.2 La Nina˜ and El Nin˜o........................... 32.3 Linking the Silicic Acid in the Southern Ocean with the Equatorial Pacific . 442.4 AnAnaloguefortheLastGlacialMaximum?.................. 452.5 Discusion..................................... 483 Silicon Isotopes as a Proxy for Silicic Acid Concentration and Utilization 513.