HR: 0800h
AN: G51A-0137    [Abstracts]
TI: Sea-level Variability in Chesapeake Bay from Autoregressive Decomposition of Tide Gauge Records
AU: * Barbosa, S M
EM: susana.barbosa@fc.up.pt
AF: Universidade Porto, Faculdade de Ciencias, Departamento de Matematica Aplicada. Rua do Campo Alegre, 687, Porto, 4169-007, Portugal
AU: Silva, M
EM: mesilva@fc.up.pt
AF: Universidade Porto, Faculdade de Ciencias, Departamento de Matematica Aplicada. Rua do Campo Alegre, 687, Porto, 4169-007, Portugal
AB: Sea-level is a fundamental parameter for the study of regional climate variability, long-term coastal management and the preservation of marine ecosystems. Tide gauge measurements of relative sea-level heights provide a fundamental dataset for examining the variability of coastal sea-level. However, a key issue in the analysis and interpretation of tide gauge records is the separation of seasonal, inter-annual and long term signals. This is a challenging task, requiring the application of specific methodologies, such as autoregressive decomposition; this model-based approach allows to obtain flexible estimates of seasonal, inter-annual and long-term variability within an adequate inferential framework, yielding optimal predictions and error bar estimates for the derived components. In this study, relative sea-level heights from 9 tide gauge stations in Chesapeake Bay, the largest estuary in the US, are analyzed. The time series of relative sea-level measurements are decomposed through autoregressive decomposition into seasonal and long-term signals. The temporal evolution of each of the decomposed signals is further analyzed, specifically by examining the temporal variability of the amplitude and phase of the seasonal signal, and by producing predictions from the long-term signals. The results show a distinct behavior, in terms of both seasonal and low-frequency variability between the 5 sites in the southern, outer part of the estuary and the 4 tide gauge stations in the northern, inner part of Chesapeake Bay.
DE: 1641 Sea level change (1222, 1225, 4556)
DE: 1872 Time series analysis (3270, 4277, 4475)
DE: 4217 Coastal processes
DE: 4235 Estuarine processes (0442)
DE: 4556 Sea level: variations and mean (1222, 1225, 1641)
SC: Geodesy [G]
MN: 2007 Fall Meeting