2. OSA = 6.6% EVERYWHERE !!! EVERYTIME !!!

3. Ocean colors:

4. OSA: main idea Some variables affect ocean surface dynamics. Some others affect 0cean Surface Albedo.  Is there common variables ? YES: wind speed, surface chlorophyll

5. How proceed ? First (small) step… Jin et al. (2004) algorithm. Cos(Solar Zenithal Angle) Optical depth (m-1) Adaptation :  no optical depth dependency  Radiative model column

6. OSA: first test How OSA-biophysical interactions impact chlorophyll concentrations at surface ? Off-line simulations with PISCES forced by monthly means of the coupled climate model IPSLCM5A on the historical period 1. On-line albedo is computed from PISCES chlorophyll at surface 2. On-line albedo modifies the solar radiation input

7. SEAWIFS HISTORICAL CHLOROPHYLL (mg/m3)

8. SEAWIFS ALBEDO CHLOROPHYLL (mg/m3)

9. OSA: second test How OSA-biophysical interactions impact ocean physics ? On-line simulations with ORCA2-LIM-PISCES forced by CORE Climatological FORCING Package 1. On-line albedo is computed from climatology of surface chlorophyll (CORE) and climatology of wind speed (CORE) 2. On-line albedo modifies the solar radiation input

10. OSA CORE Min: 6.02% Max: 9.5%

11. MarJunDec Summer Oct Winter OSA CORE – Southern Ocean Temporal Variability

12. OSA CORE – Impact on Surface Temperature Control Albedo=f(Chl+wind) Albedo=f(wind) Southern Ocean Seasonal Cycle Control Albedo=f(W) Albedo=f(Chl,W)

13. OSA CORE – Impact on Mixed Layer Depth Control Albedo=f(Chl+wind) Albedo=f(wind) Control A=f(W) A=f(Chl,W) Southern Ocean Seasonal Cycle

14. To be continued… Question ?