1. Interaction of physical, chemical and biological processes in atmosphere-ocean CO 2 exchange in the Benguela upwelling Lise Lotte Sørensen 1, Katherine Richardson 3,4, Merete B. Christiansen 2, Jesper Nissen 2, Søren Lund 2, Lars Christensen 2, Jørgen Bendtsen 1, Karen Marie Hilligsøe 1,3 and Lone Mouritsen 3 1 National Environmental Research Institute, University of Aarhus, Denmark 2 Risø-DTU, Denmark 3 University of Aarhus, Denmark 4 Copenhagen University

2. Since the world became industrialized in 1750 the atmospheric level of CO 2 has risen from 270 ppm to 380 ppm. In the same period the ocean has absorbed nearly 50% but in upwellings areas CO 2 is emitted back. As global warming increases coastal trade winds enhances (Mcgregor 2004) Does this mean more CO 2 is emitted back to the atmosphere making enhanced coastal winds an positive climate feedback process ?

3. Danish Galathea 3 cruise 2006-2007

4. ΔpCO2 measurements Measurements of partial pressure of CO2 in Sea water and in the atmosphere using an equilibrator. F CO 2 = S CO 2 k CO 2  pCO 2, Sea water is taken from continous inlet

5. Direct mesaurements of the flux of CO 2 and detailed meteorology

7. High Chlorophyll concentration at 6:00

9. Upwelling zones: CO 2 release outward crossing high chlorophyl concentration SOURCE SINK

10. Upwelling zones: CO 2 release

11. Atmospheric boundary layers

12. Conclusions Clearly the interaction between the atmosphere and ocean in terms of heat exchange and physical forcing is important to the CO 2 fluxes. Detailed description of the atmospheric flow and energy fluxes in the coastal areas are important in order to understand and estimate the CO 2 fluxes in coastal upwelling regions

13. Acknowledgement THANK YOU for your attention and THANKS to: Danish Expeditionfond Willum Kann Rasmussen Nordea Fonden FNU Knud Højgårds Fond Risø-DTU the crew on the ship ”VÆDDEREN”