The Earth Simulator Center, Japan Agency for Marine-Earth Science and Technology Authors

• Main Authors: Gurvan Madec, Marina Levy, Keiko Takahashi, Claude Tal, Rachid Benshila, Marie-alice Foujols, Arnaud Caubel, Eric Maisonnave, Charles Deltel
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.165.8171; http://www.jamstec.go.jp/esc/publication/annual/annual2006/pdf/3project/chapter6/339takahashi.pdf

This project realized in the frame a MOU between ESC and CNRS, is composed of two main themes sharing the same dynamical core of the ocean: OPA. They aim to explore (1) the impact of very shallow ocean mixed layers on the tropical climate intraseasonal variability and (2) the impact of sub-mesoscale physics on the North Atlantic balance (heat transport, nutrient cycling, CO pump), both using OPA, coupled to ECHAM5 AGCM and biogeochemical model LOBSTER respectively. 2 This report summarizes the technical and scientific achievements of both themes. The main technical achievement of the first theme is the setup of the high-resolution coupled model involving the ocean model OPA with 301 levels. Main scientific results of this first theme are first, the large impact of the diurnal cycle on Sea Surface Temperature (SST, up to 1˚C) in high vertical resolution forced experiments. Second, the first results of the coupled model show a realistic mean state and an improved equatorial variability in comparison with previous versions of the coupled model. Further work is needed to clarify the impact on the high vertical resolution in the tropical variability. The main technical achievements of the second theme are the setup of the coupled bio-physical experiments and the developments of diagnostics for the biological trends within the mixed-layer. Main scientific results of the second theme are the large impact of resolution on the turbulent and the mean state of the physics and of the biology. Regarding the physics, we see the emergence of intense submesoscale vertical velocities with resolution, together with