Estuary and Plume Forecasts in Support of Oceanographic Cruises: Generation, In-Vessel Delivery and Quality Control

Retrospective and predictive simulations of 3D estuarine and plume circulation are conducted as an integral part of CORIE, a multi-purpose cross-scale coastal-margin observatory for the Columbia River. In 2004 and 2005, daily forecasts provided near real-time support for oceanographic and fisheries cruises, involving a range of scientific goals, vessels, and regions within the estuary and the plume. The focus of this presentation is on the description of the modeling, observation and information infrastructure that was developed to support the cruises. At the core of the infrastructure were two 3D baroclinic circulation models (ELCIRC [1] and SELFE [2]), both of which solve for the shallow equations using semi-implicit, Eulerian-Lagrangian, unstructured-grid, hybrid methods (finite volumes/finite differences and finite elements/finite volumes, respectively). Short-term quality control was enabled through a near real-time observation network, combining fixed stations and vessel instrumentation. Prior to deployment, models were also extensively tested in the context of multi-year simulations and observations (e.g., [3]). Radio-based near real-time telemetry was used to transfer customized forecast products to the vessels, a process that was conducted in background every time the vessels were within radio range of a land-based station. A local web server was set-up in each vessel, allowing scientists on-board to have fast access to information. The freshness of the information available on board varied with the cruise plan (specifically, the distance to the land-based station). Typical information latency ranged from a few minutes to a few days. Forecasts were typically able to predict major features of plume and estuarine dynamics, even if the details of quantitative agreement with observations varied with ocean, wind and river conditions. [1] Y. L. Zhang, A. M. Baptista, and E. P. Myers, "A cross-scale model for 3D baroclinic circulation in estuary-plume-shelf systems: I. Formulation and skill assessment," Continental Shelf Research, 24:2187-2214, 2004. [2] Y. L. Zhang and A. M. Baptista, "A semi-implicit S-Z finite element model for cross-scale ocean circulation," International Journal for Numerical Methods in Fluids, Submitted. [3] A. M. Baptista, Y. L. Zhang, A. Chawla, M. Zulauf, C. Seaton, E. P. Myers, III, J. Kindle, M. Wilkin, M. Burla, and P. J. Turner, "A cross-scale model for 3D baroclinic circulation in estuary-plume-shelf systems: II. Application to the Columbia River," Continental Shelf Research, 25:935-972, 2005.