MODELING ETM DYNAMICS IN THE COLUMBIA RIVER ESTUARY
Situated along the Pacific coast of the Northwest United States, the Columbia River estuary features at least two ETMs. These ETMs are important biogeochemical “hotspots” and contribute to many of the ecosystem services of the estuary. High resolution modeling of ETMs is challenging for various reasons including the general complexity of salinity intrusion to the mechanisms of aggregation of primary particles into flocs near the limit of salinity intrusion. Here we present the results of the application of a sediment model to the Columbia River estuary, based on the Community Sediment Transport Model coupled to the finite element circulation model SELFE. In particular, we investigate two alternative approaches to represent flocculating sediment particles. One approach treats flocs as primary particles and the other adjusts the settling velocity of primary particles as a function of near field values of salinity and other variables. We find that both approaches reasonably reproduce both the timing and magnitude of ETM events, but their skill is diminished when the water column is fresh and the sediment distribution is dominated by flocs.
Lopez, J. E., Oregon Health and Science University, USA, email@example.com
Baptista, A. M., Oregon Health and Science University, USA, firstname.lastname@example.org
Karna, T., Oregon Health and Science University, USA, email@example.com
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall
Presentation is given by student: Yes