DYNBIO team: Isabelle Dadou (UPS), Véronique Garçon (CNRS), E. Gutknecht (CNES/Region, PhD), Briac Le Vu (MEECE Postdoc, IRD),
Collaboration within LEGOS: ECOLA : Katerina Goubanova (Postdoc IRD)
Collaboration with other laboratories: LPO (Brest, France), EME (Sète, France), IOW Warnemünde (Germany), Project funded by FP7.
Aims of this project and methods:
In this project, we investigated the potential impact of climate change in the Benguela Upwelling System (BUS), within an oxygen minimum zone, using coupled physical/biogeochemical modeling (ROMS/BioEBUS), in situ and satellite data. First, the model performances were evaluated for the present period (1980-2000) as well as for a climatological situation as compared with in situ and satellite data (climatology, cruises). Then, the potential changes for the future period (2080-2100) were analyzed in the Benguela area and compared with other oceanic areas (Baltic sea, Black sea, North Sea,…) as well as the global ocean within the MEECE project.
The performance of the coupled model (ROMS/BioEBUS) using the two embedded grids (1/4° and 1/12°) is reasonably good within the Benguela upwelling system especially for oxygen for the climatological situation due to a detailed description of the nitrification/denitrification/anammox processes. The O2 level over the entire area of the Benguela Upwelling System is controlled by the combined effects of the O2 poor-water advected by the Angola current (poleward slope current), consumption by nitrification and O2 input by mixing (Le Vu et al., in prep.).
Within the MEECE project, we used outputs of global climate simulations from the IPSL-CM4 model. A downscaling of the wind using the methodology of Goubanova et al. (2011) was needed to capture the very energetic dynamics of the BUS, both for the physics and biogeochemistry (Machu et al., 2014).
Chust., G. , J. I. Allen, L. Bopp, C. Schrum, J. Holt, K. Tsiaras, M. Zavatarelli, M. Chifflet, H. Cannaby, I. Dadou, U. Daewel, S. L. Wakelin, E. Machu, D. Pushpadas, M. Butenschon; Y. Artioli, G. Petihakis, C. Smith, V. Garçon, K. Goubanova, B. Le Vu, B. A. Fach, B. Salihoglu, E. Clementi, and X. Irigoien, 2014. Biomass change and trophic amplification of plankton in a warmer ocean, Global Change Biology, 20 (7), 2124-2139.
Dadou I., , V. Garçon, K. Goubanova, B. Le Vu, E. Machu, , Y. Shin, 2013. D3.4 Synthesis report for Climate Simulations, Part 9: Benguela. MEECE Deliverable D3.4 Synthesis report on climate simulations, http://www.meece.eu/documents/deliverables /WP3/D3%204_Part9_ Benguela.pdf
Dadou I, E. Machu, B. Le Vu, K. Goubanova, V. Garçon, 2014. Potential impact of climate change in the Benguela upwelling system using model experiments under present conditions and a potential future scenario, in preparation.
Le Vu ,B. Garçon, V., Machu,E., Gutknecht, E., Dadou,I., Paulmier A., and Sudre,J. 2014, Physical and biogeochemical processes maintaining the Oxygen Minimum Zone of the Benguela Upwelling System using an eddy resolving model, in preparation.
Machu, E., Goubanova,K., Le Vu B. Gutknecht,E. and Garçon. V., 2014, Downscaling biogeochemistry in the Benguela Eastern Boundary Current, Ocean Modelling, in revision.