Outline Importance of coastal ocean NACP Coastal Synthesis East coast carbon budget

1. Outline Importance of coastal ocean NACP Coastal Synthesis East coast carbon budget The carbon budget for coastal waters of the eastern United StatesR. Najjar, M. Friedrichs, W.-J. Cai, D. Butman,K. Kroeger, W. M. Kemp, M. Herrmann, L. McCallister, Z. Wang, S. Signorini, C. Pilskaln,D. Burdige, P. Vlahos, R. Vaillancourt

2. Importance of the coastal ocean (depth < 200 m, 4.7% of ocean area) Source: Dunne et al. (2007)

3. NACP-OCB Coastal Synthesis Activity Objective: “Stimulate the synthesis and publication of recent observational and modeling results on carbon cycle fluxes and processes along the North American continental margin” • Phase 1: Regional carbon budgets • Phase 2: Community modeling & database development • NASA & NSF support for regional workshops and post-doc • One workshop held (2012 East coast), one scheduled (Gulf of Mexico, March 27-28, 2013 in St. Petersburg, FL) • Get involved! NACP web site  Synthesis Activities

4. (Mathis) Great Lakes (McKinley) (Alin, Hales) (Cai, Freidrichs, Najjar) (Coble, Lohrenz) Nationalatlas.gov

5. The carbon cycle of the coastal ocean Tidal wetlands Estuaries Continental shelf Air-water exchange NPP Degassing River input NPP, R Respiration (R) NPP, R Open Ocean POC export Resuspension Burial POC Advective exchange DOC DIC Sediments POC BPP DOC DIC

6. Coastal zone of the eastern U.S.:Head-of-tide to shelf break (~200 m) Gulf of Maine (GoM) Georges Bank + Nantucket Shoals (GB + NS) Mid-Atlantic Bight (MAB) See workshop report on NACP web site (Najjar et al. 2012) South Atlantic Bight (SAB)

7. River input SPARROW (Shih et al. 2010) LOADEST (Stets and Striegl 2012) USGS statistical models Also using process-based model (DLEM—see Tian et al. poster)

8. Tidal wetlands www.smithtrail.net Estuarine and marine wetlands New Jersey • Current approach: • NWI • Break up wetlands by subregion and salinity • Literature survey of burial & lateral export • Average • Two estimates of NPP Delaware Bay Delaware

9. Tidal wetlands budget (Tg C yr-1) Degassing 3-19 NPP 13-24 Net uptake 5-10 2 DIC 2-6 DOC ? POC Lateral export Respiration (R) = 5-21 Burial 1-2 NPP – R = TOC export + Burial R – NPP = DIC export + Degassing Empirical model (Childers et al. 2002) being adopted/refined

10. Estuarine processes • See Herrmann et al. poster • Net ecosystem production (NEP = NPP – R) function of riverine DIN:TOC loading ratio • Burial function of estuarine residence time 64 estuaries Based on NOAA’s National Estuarine Eutrophication Assessment survey (Bricker et al. 2007)

11. East coast estuarine NEP = -1.9 Tg C yr-1 Integrate Estuarine organic C budget (Tg C yr-1) 3.4 0.6 -1.9 NEP 0.9 Canada not included yet!

12. 120 ± 30 Tg C yr-1 primary production on continental shelf Gulf of Maine (GoM) 47 ± 20 Georges Bank + Nantucket Shoals (GB + NS) Mid-Atlantic Bight (MAB) 34 ± 10 • Currently a literature synthesis • Also using satellite algorithms and numerical models • Respiration poorly constrained South Atlantic Bight (SAB) 35 ± 10

13. Continental shelf air-sea exchange (Signorini et al. poster) Surface pCO2 algorithm exploiting satellite data Flux = f(DpCO2, wind, SST) Algorithm pCO2 Observed pCO2

14. Continental shelf sediments DIC flux from sediments • DIC flux: estimated from water depth  • Similar approach taken with DOC flux • Particle flux, resuspension, burial data synthesized • See Pilskaln et al. poster

15. Cross-shelf transport • Tracer-based approach: Vlahos et al. poster • MAB a DOC source and DIC sink (net autotrophic) • Numerical modeling approach: Friedrichs et al. poster • Gives similar OC results but IC budget not in balance

16. Overall US east coast budget Tidal wetlands Estuaries Continental shelf River input 3.9 TOC 2.5 DIC NPP 13-24 Degassing 3-19 4.3 Air-water exchange ? 120 NPP, ? R 2 DIC 2-6 DOC Respiration (R) 5-21 POC export >8 Open Ocean 3-7 TOC -1.9 NEP Resuspension 12 Burial 1-2 Advective exchange Burial 0.9 Sediments POC 1 BPP DOC+DIC 14

17. Lots of progress made,but still much to do • Constrain air-water CO2 flux for estuaries  close inorganic C budget • Burial measurements • Tracer techniques to get NEP on shelf and cross-shelf transport • Numerical model evaluation and application

18. Thank you

19. Bricker, S.B., Longstaff, B., Dennison, W., Jones, A., Boicourt, K., Wicks, C., Woerner, J., 2007. Effects of nutrient enrichment in the nation’s estuaries: A decade of change, NOAA Coastal Ocean Program Decision Analysis Series No. 26. National Centers for Coastal Ocean Science, Silver Spring, MD. 328 pp. Childers, D.L., J.W. Day Jr, H. N. Mckellar (2002). Twenty More Years of Marsh and Estuarine Flux Studies: Revisiting Nixon (1980), M. P. Weinstein and D. A. Kreeger (eds), Concepts and Controversies in Tidal Marsh Ecology, Springer, Netherlands, 391-423. Dunne, J. P., J. L. Sarmiento, and A. Gnanadesikan (2007), A synthesis of global particle export from the surface ocean and cycling through the ocean interior and on the seafloor, Global Biogeochem. Cycles, 21, GB4006, doi:10.1029/2006GB002907. Najjar, R.G., Friedrichs, M.A.M., Cai, W.-J. (Editors), 2012. Report of the U.S. East Coast Carbon Cycle Synthesis Workshop, January 19-20, 2012, Ocean Carbon and Biogeochemistry Program and North American Carbon Program, 34 pp. Shih, J.S., Alexander, R.B., Smith, R.A., Boyer, E.W., Schwarz, G.E., Chung, S., 2010. An Initial SPARROW Model of Land Use and In-Stream Controls on Total Organic Carbon in Streams of the Conterminous United States, U.S. Geological Survey Open-File Report 2010–1276, 22 pp. Stets, E.G. and R.G. Striegl (2012). Carbon export by rivers draining the conterminous United States. Inland Waters, vol. 2., pp. 177-184.