Correction of inertial oscillations by assimilation of HF radar data in a model of the Ligurian Sea
Vandenbulcke, L.; Beckers, J.-M.; Barth, A. (2017). Correction of inertial oscillations by assimilation of HF radar data in a model of the Ligurian Sea. Ocean Dynamics 67(1): 117-135. https://dx.doi.org/10.1007/s10236-016-1012-5 In: Ocean Dynamics. Springer-Verlag: Berlin; Heidelberg; New York. ISSN 1616-7341; e-ISSN 1616-7228, more |  |
| Keyword | | | Author keywords | Data assimilation; High-frequency radar; Ligurian sea; Inertialoscillation |
| Abstract | This article aims at analyzing if high-frequency radar observations of surface currents allow to improve model forecasts in the Ligurian Sea, where inertial oscillations are a dominant feature. An ensemble of ROMS models covering the Ligurian Sea, and nested in the Mediterranean Forecasting System, is coupled with two WERA high-frequency radars. A sensitivity study allows to determine optimal parameters for the ensemble filter. By assimilating observations in a single point, the obtained correction shows that the forecast error covariance matrix represents the inertial oscillations, as well as large- and meso-scale processes. Furthermore, it is shown that the velocity observations can correct the phase and amplitude of the inertial oscillations. Observations are shown to have a strong effect during approximately half a day, which confirms the importance of using a high temporal observation frequency. In general, data assimilation of HF radar observations leads to a skill score of about 30% for the forecasts of surface velocity. |
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