The overarching objective of this project was to investigate physical and biogeochemical variability in the Amundsen and Ross Seas, two regions which show contrasting responses to climate change and are perhaps the least sampled in the Southern Ocean. Specifically, we addressed the extent of Circumpolar Deep Water (CDW) intrusions along the shelf, assessed freshwater inputs from glacial melt and changes in sea ice production, and examined the biogeochemical fluxes in response to the different physical environments, all in the context of surface forcing associated with large-scale climate patterns. The actual area is undergoing some conspicuous changes that include the thinning and collapsing of ice shelves and contrasting regional changes in the duration of the sea ice season. The CDW is a water mass of particular significance to physical and biological dynamics, that regionally floods the continental shelf, directly threatening the stability of ice shelves, and hence the ice sheet. Linking the climate sensitive aspects of this region to the changes in local ocean physics and biogeochemical fluxes is a key focus of this project.