The Sicily Channel Regional Model forecasting system: initial boundary conditions sensitivity and case study evaluation
- 1IMC – International Marine Centre Loc. Sa Mardini, 09170 Oristano, Italy
- 2University of Ljubljana, Department of Mathematics and Physics, Jadranska 19, Ljubljana, 1000-SI, Slovenia
- 3IAMC/CNR-Istituto Ambiente Marino Costiero, Sede di Oristano, c/o IMC-Centro Marino Internazionale Loc. Sa Mardini, 09170 Oristano, Italy
- 4ISMAR CNR sez. di La Spezia Forte Santa Teresa Pozzuolo di Lerici, 19036 La Spezia, Italy
Abstract. The Sicily Channel Regional Model forecasting system was tested using an optimization package for the initial and lateral boundary conditions. Spurious high frequency oscillations during the spin-up time were successfully reduced both in duration and magnitude by optimizing the time tendency of the free surface elevation using the Variational Initialization and Forcing Platform method developed in the framework of the Mediterranean Forecasting System Towards the Environmental Prediction project. The effect of optimization was most profound for the free surface elevation, where all oscillations with periods shorter than 4 h were suppressed.
The overall forecast skill was assessed on a 5 day case study starting on 6 April 2005, characterized by a fast passage of a deepening atmospheric low–pressure field with strong winds and marked wind direction change. We compared the predicted variables with in–situ and remotely sensed data. The forecasts of temperature, including the sea surface temperature, and salinity were quite successful, while the forecasted currents, especially within the surface layer, were not in good agreement with the measurements.