1. Carbon cycling and optics in the Gulf of Maine: Observations and Modeling Joe Salisbury Doug Vandemark Janet Campbell Fei Chai Huijie Xue Amala Mahatavan Wade McGillis

2. Goal: Reduce uncertainty in carbon flux estimates in the Gulf of Maine - Air-sea -Land-Coast -Ocean-Coast

3. Gulf of Maine and associated watersheds (left) UNH monthly transects (right)

4. Observations

5. Profilers for IOPs, AOPs, and CTD Infrared CO 2 gas analyzer Flo-thru pCO 2, oxygen, IOPs, GTD, and CTD Fast-rate CO2 equilibrator R/V Gulf Challenger UNH Field Component

6. Spatial variability in continuous measurements

7. Temporal (Interannual) Variability: Mean cross-shelf pCO2 for June-July 2004 2005

8. Air - sea interaction at Wilkinson Basin  pCO 2 (left), net flux (right) Annual flux = 12 to 20 gC/m 2 Range set by K 600 of Wanninkhof (1992) vs. Wanninkhof and McGillis (1999)

9. Modeling Efforts

10. Xue et al., CSR, in press

11. Modeled DIC (top) and Temperature (bottom) variability Mahatavan et al, GBC (2004) OPA model based on [Madec et al. [1999]]

12. Physical Model Nitrate [NO 3 ] Advection & Mixing Small Phytoplankton [P1] NO 3 Uptake Micro- Zooplankton [Z1] Grazing Ammonium [NH 4 ] Excretion NH 4 Uptake Detritus-N [DN] Fecal Pellet Sinking Silicate [Si(OH) 4 ] Diatoms [P2] Si-Uptake N-Uptake Meso- zooplankton [Z2] Sinking Detritus-Si [DSi] Grazing Fecal Pellet Sinking Predation Lost Total CO 2 [TCO 2 ] Biological Uptake Air-Sea Exchange Dissolution Carbon, Silicate, Nitrogen Ecosystem Model CoSiNE, Chai et al. 2002; Dugdale et al. 2002 Chai et al., DSR 1996 Iron

13. SeaWiFS Derived Chlorophyll Modeled Surface Chlorophyll Comparison between Model result and SeaWiFS data, April 2004

14. SeaWiFS Chlorophyll Climatology April (1998 - 2004) 18 7 6 5 4 3 2

15. Time series comparison EMCCWMCC Georges Bank (1) Wilkinson Basin (5) ModelSeaWiFS

16. High Resolution Circulation Modeling and Remote Sensing

17. 31 20 Gulf of Maine Circulation Model (H. Xue, UMO) Sea Surface Salinity (psu) (3/17/05 1000 EST)

18. 8282 Gulf of Maine Circulation Model (H. Xue, UMO) Sea Surface Temp ( o C)

19. 550 350 MODIS Assessment of pCO 2 pCO 2 (  atm) (3/17/05 1030 EST)

20. NEM (  g L -1 d -1 ) estimate on 3/17/05 based on modeled alkalinity and DIC B derived by satellite-retrieved pCO 2 and modeled SST and SSS. n=126 RSME= 5.7 (  g L -1 d -1 ), r 2 = 0.59 15 -15 0 Net Ecosystem Metabolism (  g L -1 d -1 ) 3/17/05 1000EST Estimated from: Modeled Alkalinity MODIS pCO2 Modeled DIC

21. IOP and SST variability versus pCO2 pCO2 retrieval based on classification of optical provinces Carbon and optics

22. Final comments: Off to a good start - team assembled, growing database of quality measurements Modeling and remote sensing of carbon parameters encouraging Budgets and error estimates forthcoming The end - thanks