2024-03-29T12:48:37Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/270222020-11-12T09:35:57Zcom_10261_123com_10261_8col_10261_376
Relative performance of future altimeter systems and tide gauges in constraining a model of North Sea high-frequency barotropic dynamics
Mourre, Baptiste
De Mey, Pierre
Ménard, Yves
Lyard, Florent
Le Provost, Christian
North Sea
Barotropic dynamics
Wide swath ocean altimeter
Altimeter constellation
Tide gauges
Ensemble Kalman Filter
14 pages, 13 figures, 1 table
We evaluate in this paper the ability of several altimeter systems, considered separately as well as together with tide gauges, to control the time evolution of a barotropic model of the North Sea shelf. This evaluation is performed in the framework of the particular model errors due to uncertainties in bathymetry. An Ensemble Kalman Filter (EnKF) data assimilation approach is adopted, and observing-systems simulation experiments (OSSEs) are carried out using ensemble spread statistics. The skill criterion for the comparison of observing networks is, therefore, not based on the misfit between two simulations, as done in classic twin experiments, but on the reduction of ensemble variance occurring as a consequence of the assimilation. Future altimeter systems, such as the Wide Swath Ocean Altimeter (WSOA) and satellite constellations, are considered in this work. A single WSOA exhibits, for instance, similar performance as two-nadir satellites in terms of sea-level correction, and is better than three satellites in terms of model velocity control. Generally speaking, the temporal resolution of observations is shown to be of major importance for controlling the model error in these experiments. This result is clearly related to the focus adopted in this study on the specific high-frequency response of the ocean to meteorological forcing. Altimeter systems lack adequate temporal sampling for properly correcting the major part of model error in this context, whereas tide gauges, which provide a much finer time resolution, lead to better global statistical performance. When looking into further detail, tide gauges and altimetry are demonstrated to exhibit an interesting complementary character over the whole shelf, as tide gauge networks make it possible to properly control model error in a ∼100-km coastal band, while high-resolution altimeter systems are more efficient farther from the coast
This work was jointly supported by the Centre National d'Etudes Spatiales (CNES) and the Centre de la recherche Scientifique (CNRS)
Peer reviewed
2010-08-12T10:42:52Z
2010-08-12T10:42:52Z
2006-12
artículo
http://purl.org/coar/resource_type/c_6501
Ocean Dynamics 56(5-6): 473-486 (2006)
1616-7341
http://hdl.handle.net/10261/27022
10.1007/s10236-006-0081-2
en
https://doi.org/10.1007/s10236-006-0081-2
none
5867 bytes
application/pdf
Springer