Relationship Between Physical and Biological Properties on the Microscale: A Cross-Comparison Between Differing Coastal Domains

Abstract

Our long-term goal is to quantify the interactions between small-scale biological and physical processes within the upper ocean. Attenuation of light and sound propagation in the upper ocean is tightly linked to the patterns of vertical distribution of particulate matter (primarily detritus, phytoplankton, and zooplankton). Local maxima in these distributions frequently occur within the euphotic zone, and are often concentrated within depth intervals that are less than 1-2m thick (e.g., Dekshenieks et al. 2001, Cowles 2004). Of particular interest are the steep vertical gradients of stratification and/or shear that often exist at the boundaries of these thin plankton layers, and which are implicated in their formation and maintenance (e.g., Stacey et al. 2007, Birch et al. 2008). We are extending the analysis of thin plankton layers by examining the microstructure datasets obtained over the past decade by the Ocean Mixing Group at Oregon State University. Tens of thousands of profiles have been obtained over the central Oregon shelf (COAST), over the New Jersey shelf (SW06), and around and through the buoyant Columbia River plume (RISE). Plots of cross-shelf property distributions have revealed extensive layers of enhanced particulate biomass. Over the Oregon continental shelf in 2001, successive cross-shelf transects consistently revealed filaments of turbidity that extended O(10km). Chameleon profiles obtained off the Washington coast in 2006 also detected layers of enhanced chlorophyll fluorescence that appeared to occur in vertical intervals of relatively low TKE dissipation. In the original processing, the physical dynamics in and around these turbidity and chlorophyll features were not examined. We are now addressing the explicit relationships between these features.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2009
Accession Number
ADA527132

Entities

People

  • James N. Moum
  • Jonathan D. Nash
  • Timothy J. Cowles

Organizations

  • Oregon State University

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Atmospheric Sciences
  • Chlorophylls
  • Columbia River
  • Continental Shelves
  • Dissipation
  • Euphotic Zones
  • Fluorescence
  • Intervals
  • Layers
  • Microbalances
  • Mixing
  • Oceanography
  • Oceans
  • Particulate Matter
  • Particulates
  • Plankton
  • Universities

Fields of Study

  • Environmental science

Readers

  • Coastal Oceanography
  • Marine Ecotoxicology