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In this paper we consider flexural-gravity waves propagating in a layer of water of constant depth limited by a vertical wall simulating a straight coastline. The water surface is covered with an elastic ice sheet of constant thickness. The ice sheet is split by one or two straight cracks parallel to the coastline, simulating the structure of land-fast ice with a refrozen lead. Analytical solutions of hydrodynamic equations describing the interaction of flexural-gravity waves with the ice sheet and cracks have been constructed and studied. In this paper, the amplification of the amplitude of incident waves between the shoreline and cracks was described depending on the incident angle of the wave coming from offshore. The constructed solutions allow the existence of edge waves propagating along the coastline and attenuated offshore. The energy of edge waves is trapped between the coastline and ice cracks. The application of the constructed solutions to describe wave phenomena observed in the land-fast ice of the Arctic shelf of Alaska is discussed.

Abstract Variability in sea ice conditions, combined with strong couplings to the atmosphere and the ocean, lead to a broad range of complex sea ice dynamics. More in-situ measurements are needed to better identify the phenomena and mechanisms that govern sea ice growth, drift, and breakup. To this end, we have gathered a dataset of in-situ observations of sea ice drift and waves in ice. A total of 15 deployments were performed over a period of 5 years in both the Arctic and Antarctic, involving 72 instruments. These provide both GPS drift tracks, and measurements of waves in ice. The data can, in turn, be used for tuning sea ice drift models, investigating waves damping by sea ice, and helping calibrate other sea ice measurement techniques, such as satellite based observations.

The paper is focusing on the tides and on the strong tidal current generated in the western fjords of Svalbard. Numerical model is chosen as a tool to study the barotropic tides. Model results are compared against measured sea level and drifters. Numerical modeling and observation of tides point that the tidal amplitude does not change strongly in these fjords but the tidal currents are enhanced in several locations, namely at the entrance to the Dickson Fjord, in the narrow passages in proximity to Svea, and in the central part of Van Keulenfjorden. As the strongest currents have been found at the passages at Akseløya Island we have focused our research on this location. The narrow northern channel (Akselsundet) at Akseløya is the main waterway to Svea coal mines. Tidal currents computed and observed at the northern tip of Akseløya Island can reach amplitude from 2 to 3 m s−1. Observation of the deployed drifters and calculation of the seeded particles in the passage at Akseløya depicted a complicated pattern of eddies. The jet-like currents and eddies are quite different at the ebb and flood tide phases. As the Akseløya Island orientation relative to the shore is different for the flood and ebb waters the flow through Akselsundet is differently constrained by this geometry. The observations show that the oscillating tidal motion causes large excursions of the water particle. The drifters released in the passage during flood ended up trapped in the eddy on the eastern side of the island.