Ocean Science
www.ocean-sci.net
1812-0784
1812-0792
3
1
2007
10.5194/os-3-31-2007
http://www.ocean-sci.net/3/31/2007/
http://www.ocean-sci.net/3/31/2007/os-3-31-2007.html
http://www.ocean-sci.net/3/31/2007/os-3-31-2007.pdf
31
41
2007-01-30
The Sicily Channel Regional Model forecasting system: initial boundary conditions sensitivity and case study evaluation
S. Gaberšek
gaberseksasa@gmail.com
R. Sorgente
S. Natale
A. Ribotti
A. Olita
M. Astraldi
M. Borghini
IMC – International Marine Centre Loc. Sa Mardini, 09170 Oristano, Italy
University of Ljubljana, Department of Mathematics and Physics, Jadranska 19, Ljubljana, 1000-SI, Slovenia
IAMC/CNR-Istituto Ambiente Marino Costiero, Sede di Oristano, c/o IMC-Centro Marino Internazionale Loc. Sa Mardini, 09170 Oristano, Italy
ISMAR CNR sez. di La Spezia Forte Santa Teresa Pozzuolo di Lerici, 19036 La Spezia, Italy
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.
<br><br>
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.
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