Program and Agenda

Abstract

OBSERVATIONS OF TURBULENCE AND MIXING IN THE COLUMBIA RIVER ESTUARY

The Columbia River estuarine turbidity maxima (ETM) is a biological hotspot where increased residence times and high particle concentrations accelerate biogeochemical processes. Ongoing development of the Virtual Columbia River modeling system aims to address the physical processes leading to the formation, maintenance and destruction of the ETM. Large tidal velocities and strong gradients of salinity and turbidity complicate numerical modeling and require robust observations to improve turbulence parameterizations and validate model predictions. To complement these modeling efforts, a continuously profiling instrument package was deployed in the Columbia River ETM region in Fall 2012. The Winched Profiler platform integrates fine- and micro-scale sensors including a CTD, ADV, LISST-100X, micro-C and micro-T probes, shear probes, dissolved oxygen, and fluorometers to measure physical and biogeochemical properties throughout the water column. Observations of salinity, tidal velocities, and derived turbulence properties are presented. Turbulent kinetic energy (TKE) production and dissipation were greatest near the bed during unstratified conditions and low gradient Richardson numbers, but reached a mid-depth minimum when strong stratification was present at the site. Eddy viscosities estimated from the profiler observations were compared against model results to quantify mixing.

ePoster:

Authors

Rinehimer, J. P., NSF Science and Technology Center for Coastal Margin Observation & Prediction, OHSU, USA, jprine@ohsu.edu

Sanford, T. B., Applied Physics Lab, University of Washington, USA, sanford@apl.washington.edu

Kärnä, T., NSF Science and Technology Center for Coastal Margin Observation & Prediction, OHSU, USA, karnat@stccmop.org

Baptista, A. M., NSF Science and Technology Center for Coastal Margin Observation & Prediction, OHSU, USA, baptista@stccmop.org

Details

Poster presentation

Session #:003
Date: 2/26/2014
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall

Presentation is given by student: No

PosterID: 785