Barotropic waves in a sloping two- and multiple-basin Arctic ocean model

Large-scale barotropic flow in the Arctic Ocean is strongly steered by the seafloor topography, yet how this geometry constrains free modes and facilitates inter-basin interactions remains unclear. Free modes conserve potential vorticity and at high latitudes the circulation pathway is enclosed by its sloping two-basin geometry. We begin by presenting a simple two-basin model, representing the Canadian and Eurasian basin respectively, with sloping boundaries and flat bottoms to explore simplified Arctic flow behaviour. Topographic Rossby waves are analytically obtained and the two basins are linked together via a mode-matching framework. We show free modes are tightly constrained to geometry, with basin-trapped dipole wave modes only emerging in certain geometric parameters. We then extend this to a more realistic, multiple-basin Arctic Ocean model that include the Nordic seas, and demonstrate the transmission and exchange of these topographic waves across these multiple sloping basins.