Naslov
A new approach to bathymetry smoothing in sigma-coordinate ocean models

Autori
Dutour-Sikirić, Mathieu ; Janeković, Ivica ; Kuzmić, Milivoj

Izvornik
Ocean modelling (1463-5003) 29 (2009), 2; 128-136

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
bathymetry smoothing ; filter ; linear programming

Sažetak
Sigma-coordinate ocean models are currently used in large basin and coastal seas simulations. When there is a 19 strongly varying bathymetry, r-coordinate system solutions exhibit an intrinsic error in the horizontal 20 pressure gradient (HPG) term. In this paper, a new, linear programming (LP) procedure has been pro- 21 posed to deal with this problem. The success of the procedure in alleviating HPG error is gauged in com- 22 parison with two implementations of the Shapiro filter, the Mellor-Ezer-Oey (1994) algorithm (MEO), 23 and the recently (2006) proposed procedure of Martinho and Batteen (MB). All are applied to three idea- 24 lised cases and then to the Adriatic Sea, as modelled with the Rutgers version of ROMS. The comparisons 25 reveal that even the improved Shapiro filter creates very large modifications to the bathymetry and 26 should be avoided. The MB procedure performance is comparable to that of LP when the slope factor 27 is larger than approximately 0.2, and inferior to it at smaller slope factor values. In cases where volume 28 conservation is required, the MB method is inferior to both MEO and LP. The difference between the 29 above-mentioned solutions is more pronounced for coarser grids.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

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