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.
  

OS32D-148

Observations of the Details of Coastal Upwelling Response and
Relaxation Across a Simple Bathymetry

Alexander Perlin, James N. Moum and Jody M. Klymak

College of Oceanic and Atmospheric Sciences, Oregon State University

New and detailed observations of the response of the coastal ocean
off central Oregon to two cycles of northerly (upwelling) winds were
made as part of the COAST experiment in the spring and summer of
2001. These observations included continuous turbulence profiling
of the full water column, including the bottom boundary layer,
using Chameleon. Preliminary analysis reveals several aspects:
1. High turbulence levels beneath the southward coastal jet and
in the bottom boundary layer during upwelling. 2. Relaxation of
the ocean following cessation of upwelling winds is marked by a
northward flow inshore and high turbulence levels throughout the
water column. 3. A strong internal tide frequently dominates the
cross-shelf flow field and energizes the bottom boundary layer. A
two-day time series at midshelf helps to quantify the effect on
the upwelling circulation. 4. Dense bottom fluid migrates up the
sloping shelf at peak speeds of 9 cm/s in response to upwelling
and in agreement with an estimate from Ekman transport. It then
migrates back down during relaxation.  5. Cross-shelf transport
of fluid is revealed by thin tendrils of fluid in mid-water column
with high optical backscatter (880 nm), propagating from the highly
productive inner shelf. These tendrils are high in chlorophyll. These
observations were made as part of the COAST experiment.