Numerical simulation of wind waves at the Río de la Plata: evaluation of four global atmospheric databases

MARTIN, PAULA; DRAGANI, WALTER; CERNE, BIBIANA; ALONSO, GUADALUPE; PESCIO, ANDRES; PRARIO, BARBARA

BRAZILIAN JOURNAL OF OCEANOGRAPHY

INST OCEANOGRAFICO

Lugar: São Paulo; Año: 2012 vol. 60 p. 501 - 511

1679-8759

The performances of NCEP/NCAR I, NCEP/DOE II, Japanese 25-year and ERA-Interim global databases, implemented as atmospheric forcings of SWAN model in the Río de la Plata region, were quantitatively tested by calculating the bias, the mean root square error, the determination coefficient and the slope of the line fitted between observed and simulated wave parameters (significant wave height, mean period and direction).  Even though statistic estimators did not show evident differences for wave periods and directions some noticeable differences were observed for simulated significant wave heights depending on the forcing used. The lowest bias (0.22 m) was obtained when SWAN model was forced by ERA-Interim. With regards to the mean root square errors, the lowest values were obtained when NCEP/NCAR I (0.16 m) and NCEP/DOE II (0.19 m) were used as forcing. In addition, the best slope for simulated heights (0.79) was obtained using NCEP/DOE II. Computed determination coefficient for heights, periods and directions were very similar (0.89-0.93) for all the simulations carried out in this work. Energetic and severe wave events were specially considered. The most energetic wave episode recorded at the Río de la Plata mouth (24 August, 2005) was  analyzed and discussed in particular. It was concluded that during energetic atmospheric conditions the best agreement is achieved implementing NCEP/DOE II as forcing. In the light of these results it is concluded that NCEP/DOE II is the most suitable atmospheric forcing to simulate wave heights with SWAN model in the Río de la Plata region.