Wind wave variability in Hornsund fjord, west Spitsbergen

In this study, the third-generation spectral wave model Simulating WAves Nearshore (SWAN) is applied to an analysis of wind wave conditions in Hornsund, a relatively small fjord in the southwestern part of Spitsbergen (Svalbard Archipelago). The model is run on a series of three nested grids with increasing spatial resolution. Wave energy spectra from a large-scale WAVEWATCH III model, wind from the Global Forecast System, and water levels from a tidal model of the Arctic Ocean are used as input data. The modelling results are validated against observational data from four coastal locations within Hornsund: one in Gåshamna and three in Isbjørnhamna/Hansbukta (I/H), which is the main area of interest in this study. Within the frequency range available in observations (<0.15 Hz), the model reproduces the total wave energy with high accuracy (bias below 4 cm, correlation above 0.9), with slight under-/overestimation of energy below/above 0.1 Hz, leading to underestimated mean wave periods (negative bias of 0.65–1.14 s, correlation 0.63–0.78). We analyze transformation of wave energy spectra from the open boundary to the inner parts of Hornsund and perform a detailed analysis of wave conditions in I/H area, identifying the dominating wave patterns and their relationships with wind and open-ocean wave forcing.