TY - JOUR
T1 - Seasonal and interannual variability of the Columbia River plume
T2 - A perspective enabled by multiyear simulation databases
AU - Burla, Michela
AU - Baptista, António M.
AU - Zhang, Yinglong
AU - Frolov, Sergey
N1 - Funding Information:
[54] Acknowledgments. The National Science Foundation (OCE-0622278, OCE-0424602) provided financial support for this research. The study relied on results from the CORIE/SATURN modeling system. Thanks are due to the following members of the CORIE/SATURN team: to Paul Turner and Charles Seaton for their contributions to generating the circulation databases and related information products and generation of Figure 1 and to Mike Wilkin and other field crew for their effort in maintaining CORIE observational network. We also thank Barbara Hickey and Ed Dever for providing the observational data sets from the RISE buoys and two anonymous reviewers and an associate editor, whose comments helped to improve this manuscript. Any statements, opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views or policies of the federal sponsors and no official endorsement should be inferred.
Publisher Copyright:
© 2010 by the American Geophysical Union.
PY - 2010/1/30
Y1 - 2010/1/30
N2 - As integral capability within an end-to-end observatory for the Columbia River estuary-plume-shelf system, we routinely create simulation databases of 3-D baroclinic circulation with unstructured grid models SELFE (Semi-implicit Eulerian-Lagrangian Finite Element) and ELCIRC (Eulerian-Lagrangian Circulation). Here, 1999–2006 SELFE simulations are used to study plume variability at multiple temporal scales: interannual, seasonal, and event scale. Time series of plume metrics, together with climatology and anomalies of surface salinity, suggest that simulations usefully capture key features of plume dynamics. In particular, simulations capture seasonal variability around two known trends: a coastally attached northward winter plume and a detached southward summer plume. Results show significant interannual variability of the plume orientation and extent, with potential implications on the variability of productivity in the system. An empirical orthogonal function analysis confirms that a bidirectional plume is prevalent in summer, showing that the result holds true regardless of interannual variability. Short-term bidirectional plumes, previously observed or modeled only in summer, can also occasionally develop in winter as a result of episodically strong upwelling-favorable winds. Across years, the predominantly coastal attached northward plume in late fall and winter is found to separate frequently from the coast, during wind relaxation events or weak wind reversals. Multiple skill scores are used to evaluate the quality of the simulations against earlier circulation databases and data. Analysis of root-mean-square error and bias suggests overall superiority of SELFE-generated over ELCIRC-generated simulation databases, but the generality of the conclusions is limited by (1) models not being the only difference between simulation databases and (2) no model prevailing across all error metrics.
AB - As integral capability within an end-to-end observatory for the Columbia River estuary-plume-shelf system, we routinely create simulation databases of 3-D baroclinic circulation with unstructured grid models SELFE (Semi-implicit Eulerian-Lagrangian Finite Element) and ELCIRC (Eulerian-Lagrangian Circulation). Here, 1999–2006 SELFE simulations are used to study plume variability at multiple temporal scales: interannual, seasonal, and event scale. Time series of plume metrics, together with climatology and anomalies of surface salinity, suggest that simulations usefully capture key features of plume dynamics. In particular, simulations capture seasonal variability around two known trends: a coastally attached northward winter plume and a detached southward summer plume. Results show significant interannual variability of the plume orientation and extent, with potential implications on the variability of productivity in the system. An empirical orthogonal function analysis confirms that a bidirectional plume is prevalent in summer, showing that the result holds true regardless of interannual variability. Short-term bidirectional plumes, previously observed or modeled only in summer, can also occasionally develop in winter as a result of episodically strong upwelling-favorable winds. Across years, the predominantly coastal attached northward plume in late fall and winter is found to separate frequently from the coast, during wind relaxation events or weak wind reversals. Multiple skill scores are used to evaluate the quality of the simulations against earlier circulation databases and data. Analysis of root-mean-square error and bias suggests overall superiority of SELFE-generated over ELCIRC-generated simulation databases, but the generality of the conclusions is limited by (1) models not being the only difference between simulation databases and (2) no model prevailing across all error metrics.
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U2 - 10.1029/2008JC004964
DO - 10.1029/2008JC004964
M3 - Article
AN - SCOPUS:84962048419
VL - 115
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
SN - 0148-0227
IS - C2
M1 - C00B16
ER -