Talk by Johannes Gemmrich

(University of Victoria, Canada)


The Strait of Georgia is an inland sea about 200 km long and 30km wide, separating the Canadian mainland and Vancouver Island. About 10% of Canada's population lives on the shores of the Strait, and the waters of the Strait are heavily used for recreational and commercial purposes; this includes traffic to and from Canada’s largest port, as well as ~80/day ferry sailings across the Strait. Weather and wind conditions around the Strait can vary spatially and on short temporal scales, due to the surrounding rugged mountain topography, with elevations of more than 1000 m bordering the coast.

Spectral wave forecast models achieve remarkable skills in open ocean conditions, due to recent improvements of the representation of relevant wave physics. However, the conditions in coastal and enclosed seas still represent a challenge for spectral wave models. Here, we discuss some of these challenges and present results from a 2-year run of Wavewatch III ® for the Strait of Georgia. The model resolution is 500m on a regular grid; surface currents are provided by a 1km resolution NEMO circulation model, and winds are taken from a 2.5km resolution atmospheric model. The model captures intermediate and major wind and wave events reasonably well, and highlights some of the variations on short spatial scales, that are not covered by the limited observations or the general marine forecast.