Recent wave conditions in Hornsund, Svalbard from in situ measurements

Over the last decades, the Atlantic sector of the Arctic has been experiencing more frequent, longer and more severe storms. At the same time the extent and duration of the sea ice cover has been decreasing, contributing to longer potential fetch, the distance over which waves grow. The number of ice-free days has been increasing for many coastal areas. Bigger waves operating at the coast over a longer time period may cause erosion, wave overtopping and flooding, putting coastal societies and infrastructure at risk. In situ wave measurements are critical for understanding wave climate, analysing trends, and calibrating and validating wave models. Continuous wave data are sparse in e.g. Svalbard and Greenland, where communities and infrastructure (industry, research) exist. To fill this gap, we set up a monitoring program in Hornsund fjord, SW Spitsbergen, Svalbard where Polish Polar Station (PPS) is located. Since July 2013 water pressure has been continuously recorded using RBR sensors mounted at the bottom (8-23 m depth) of various bays in northern (Hansbukta, Isbjornhamna, Veslebogen) and southern (Gashamna) parts of the fjord. We processed the data using standard techniques and obtained sea level (tides), wave spectra, and bulk wave parameters at hourly frequency. This dataset is freely available. We characterise recent wave conditions in Hornsund, identify spatial and temporal (seasonal to interannual) trends, and discuss the impact of the nearshore wave conditions on coastal change and infrastructure damage.