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Topic #1: Coastal Zones & Carbon Cycle. Importance of study of coastal zones in the carbon cycle has been explicated by two major carbon science steering documents: The North American Carbon Plan (NACP) [ Wofsy et al ., 2002]
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Topic #1: Coastal Zones & Carbon Cycle Importance of study of coastal zones in the carbon cycle has been explicated by two major carbon science steering documents: The North American Carbon Plan (NACP) [Wofsy et al., 2002] “carbon cycling on the continental margins is poorly understood and is under sampled to the point that it is uncertain whether these regions are a net sink or a net source of CO2 to the atmosphere.” And from Ocean Carbon & Climate Change [Doney et al., 2004]: “Many basic aspects of the ocean carbon system are inadequately understood…[e.g.,] land-ocean exchange and carbon cycling in the coastal ocean and along continental margins”. NCAR ECSA Workshop on Coastal Zones June 2004
Some recent C budget studies Ship-based studies in the East China Sea [Tsunogai et al., 1999] and off the West Coast of Europe [Frankignoulle et al., 2001] have suggested that the coastal ocean plays a significant role in the global carbon cycle… Frankignoulle et al. estimate the European coastal sink to be almost half as large as that proposed for the open North Atlantic. NCAR ECSA Workshop on Coastal Zones June 2004
Schematic of coastal processes NCAR ECSA Workshop on Coastal Zones June 2004
Shelf area ~7% of ocean surface WORLDBATH topography (IRB Climate Data library) NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing - winds NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing – eastern boundary currents Aleutian Current H California Current NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing - upwelling • Three Competing Models of Cold Filaments: • “Squirts” (1-Way Jets): transport to deep ocean • Mesoscale Eddies: random, diffusive transport • Meandering Jet: very little offshore transport • Surface drifters show ~2 week transport times to a couple hundred kilometers offshore. • Strong gradients in zooplankton populations in the region of the main coastal jet. • Large time lag between blooms in nutrient rich waters and DMS release. Strub et al., JGR-Oceans, 98 (C8), 1991 NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing – eddy transport from Melsom et al., Earth Interactions, 1999[http://projects.dnmi.no/~telecon/EI/main.html] NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing – riverine inputs ← from Curry & Webster [1999] ↓from Dai & Trenberth [2002]Volumes in km3 yr-1Drainage Area (DA) in 103 km2 NCAR ECSA Workshop on Coastal Zones June 2004
Physical forcing – riverine inputs NCAR ECSA Workshop on Coastal Zones June 2004
Biological response SeaWiFS Chl-A (July 2001) NCAR ECSA Workshop on Coastal Zones June 2004
Canadian JGOFS Cruises to the NE Subarctic Pacific JGOFS ISep 92Mar 93May 93Feb 94May 94Sep 94JGOFS IIAug 95Feb 96May 96Aug 96Feb 97Jun 97 NCAR ECSA Workshop on Coastal Zones June 2004
Phytoplankton Species Composition along Line P NCAR ECSA Workshop on Coastal Zones June 2004
New primary production in the Oceanic NE Pacific JGOFS I: 1992-1994 JGOFS II: 1995-1997 Re-estimate of new production: 33% NCAR ECSA Workshop on Coastal Zones June 2004
SeaWiFs image of Asian dust cloud Spring 2001 NASA website NCAR ECSA Workshop on Coastal Zones June 2004
Proportion of new production Proportion of new production Silicic Acid and Nitrate Uptake West of Vancouver Island May 98 NCAR ECSA Workshop on Coastal Zones June 2004
