Arctic Ocean bathymetry and its connections to tectonics, oceanography and climate

For at least the past 50 million years, the Arctic region has had a major role in regulating global climate regimes and their variations through time. In this Review, we discuss the role of the Arctic oceanic basin and its complex bathymetry in controlling ocean circulation and marine cryosphere development. The spatial distribution and depth of various seafloor features, such as ocean gateways, submarine plateaus and continental shelves, influence the pathways of ocean currents, both today and in the past. The Arctic Ocean was an enclosed basin until the Early Eocene (56–48 million years ago), when the Eurasian Basin started to form and a shallow sea connected the Arctic to the Tethys Ocean. The connections with the North Atlantic and the global ocean through shallow and deep gateways prompted the transition from a global greenhouse to icehouse climate. However, the Arctic Ocean remains underexplored, as less than one-quarter of its seafloor is mapped in detail. Future integrated geoscience research, modern bathymetric mapping technology and active international programmes are needed to close these data gaps. Changes in seafloor topography, resulting from tectonic, magmatic and sedimentary processes, influence Arctic and global climate via a multitude of impacts on ocean pathways and energetics. This Review explores the past and present links between Arctic bathymetry, tectonics, oceans and climate.