AGU Ocean Sciences Meeting (Feb. 2002) COAST abstracts:

• Ashe et al.
  
• Bane et al.
  
• Barth et al.
  
• Coletti et al.
  
• Haines et al.
  
• Karp-Boss et al.
  
• Kosro et al.
  
• Kurapov et al.
  
• Okeefe et al.
  
• Ott et al.
  
• Perlin et al.
  
• Ruttenberg et al.
  
• Sutor et al.
  

OS22D-222

Organic material in the Oregon upwelling zone: distributions and processes

Lee Karp-Boss, Patricia A. Wheeler, Burke Hales, and Paul Covert

College of Oceanic and Atmospheric Sciences, Oregon State University

The upwelling system off the Oregon coast is characterized by high
biological productivity. Despite conceptual and quantitative advances
in the understanding of upwelling systems, little is known about
the processes that control distributions and fate of organic matter
in such systems. As part of the Coastal Ocean Advances in Shelf
Transport (COAST) project we studied distributions of chlorophyll
and particulate and dissolved organic matter.  These measurements
were done in conjunction with high-resolution measurements of
physical and chemical parameters. Preliminary results show high, but
greatly variable (in space and time), concentrations of chlorophyll,
particulate organic carbon (POC) and particulate organic nitrogen
(PON) at the surface.  A persistent feature, observed over the
shelf, is the presence of elevated concentrations of chlorophyll
(2-28 mg/l), POC (90-740 mg/l) and PON (18-125 mg/l) near the bottom
(at 25-50 m). A minimum in the concentrations of these parameters was
typically observed in the middle portion of the water column. POC and
PON near the bottom are strongly correlated with chlorophyll. C/N
ratios further suggest that this organic material is relatively
fresh. Processes that could lead to observed distributions and
their implications to the dynamics of organic material in the Oregon
upwelling zone will be discussed.