1. Ecosystem composition and export production variability Corinne Le Quéré, Erik Buitenhuis, Christine Klaas Max-Planck-Institute for Biogeochemistry, Germany and Olivier Aumont Laboratoire de Dynamique du Climat et des Océans, France

2. 1850today2100 CO 2 sink (PgC/y) Prentice et al., 2001 OCEAN LAND climate feedback

3. 4 NPZD PISCES Dynamic Green Ocean Model (DGOM)

4. SeaWiFS Chla (mgChl/m3)

5. SeaWiFS NPZD PISCES DGOM Chla (mgChl/m3)

6. SeaWiFS 50% Interannual standard deviation of Chla (%) Chla (mgChl/m3)

7. SeaWiFS NPZD PISCES DGOM 50% Interannual standard deviation of Chla (%) Chla (mgChl/m3)

8. NanoCocco.Diatoms Description maximum growth rate µ at 0°C (1/d) 0.60.40.6 half sat. P (nM)19475 half sat. Si (µM)2 half sat. Fe (pM)20 120 Light affinity dependence664 Phytoplankton traits

9. cocco diatoms nano Abundance of PFT (%) DGOM cocco diatoms nano 70N 0 70S relative contribution

10. cocco diatoms nano Interannual standard deviation of chla per PFT (%)

11. cocco diatoms nanno Interannual standard deviation of chla per PFT (%) 5 PFTs4 PFTs

12. 1997 1998 1999 2000 2001 2002 2003 diatoms coccolithophorids nano phytoplankton 0.02 0.1 1.5 Plankton-specific chla in the North Atlantic (40N-45N, mgChla/m3)

13. DGOM Abundance of diatoms (%) Uitz, Claustre et al., from an HPLC pigment and SeaWIFS Chla cocco diatoms nano 70N 0 70S relative contribution

14. Coccolithophorid bloom frequency Analysis from C. Brown cocco diatoms nano DGOM 70N 0 70S relative contribution

15. MEAN (Standard deviation) Export Production (PgC/y)

16. sensitivity of plankton biomass to growth grazing diatoms nano Cocco. Meso-zoo Micro-zoo diatoms nano Cocco. Meso-zoo Micro-zoo

17. Conclusions More complexity in marine ecosystems gives more variability in fluxes More in line with observations Mean spatial distribution in PFTs is critical to reproduce chl variability

19. DescriptionPCULDGSWSWAMSWFESWPOSWSI half sat. P diatoms (nM)75 3007530075 half sat. P nano/pico(nM)19 1001910019 half sat. P Coccolith. (nM) 44444 half sat. Si Diatoms (µM) 440.444 half sat. Fe diatoms (aM)120 700 120 half sat. Fe nano/pico (aM)25 300 25 half sat. Fe Coccolith. (aM9 25300 25 Phytoplankton traits

20. DescriptionUnitsPCULDGSW SWA M SWFESWPO SWS I half saturation PO 4 diatoms nM75 3007530075 half saturation PO 4 nanophytoplankton nM19 1001910019 half saturation PO 4 coccolithopho rids nM44444 half saturation SiO 3 diatoms µM440.444 half saturation Fe diatoms aM120 700 120 half saturation Fe nanophytoplankton aM25 300 25 half saturation Fe coccolithopho rids aM25300 25 Phytoplankton traits

21. DescriptionPCULEQULEME2EMESEMI2EMIC max. growth rate Meso-zoo (1/d) 0.90.24 0.90.24 half sat. Meso-zoo (µM)180.29 mortality rate Meso-zoo (1/d) 0.1*mes0.0580.058*mes0.1*mes0.058 max growth rate Micro-zoo (1/d) 422242 half saturation Micro-zoo (µM) 18 3 Zooplankton traits

22. DescriptionUnitsPCULEQULEME2EMESEMI2 EMI C max. growth rate mesozooplan kton 1/d0.90.24 0.90.24 half saturation mes µMµM180.29 mortality rate mes 1/d 0.1*m es 0.058 0.058 *mes 0.1*m es 0.058 max growth rate microzoopla nkton 1/d422242 half saturation mic µMµM18 3 Zooplankton traits

23. POC CaCO3 Si sediment trap data base of C. Klaas Impact of El Nino in % on Chla (full line from SeaWiFS) and export (dots from traps)

24. cocco diatoms nanno Abundance of PFT (%) DGOMPISCES