Abstract

The largest changes in the circulation of the South-eastern Pacific resulting from global warming are associated with the southward shift and intensification of the anticyclone and with coastal surface warming. Coastal upwelling is projected to be increase off central Chile, due to an increase in equatorward winds, although increased oceanic stratification and associated enhanced nearshore turbulence will yield an onshore deepening/flattening of the thermocline. The overall increase in south-easterly trade winds of the South-eastern Pacific in a warmer climate are likely to increase the connectivity pattern between Juan Fernandez and Desventuradas islands, and along the Sala y Gomez ridge, through increasing wind-driven mean ocean currents. Deoxygenation associated with the warmer temperatures and changes in ventilation are likely to modify marine habitat and the respiratory barriers of species in the seamounts located in the vicinity of the limits of the minimum oxygen zone. In the South-eastern Pacific, the prevailing 2D understanding of the responses of marine life to climate change needs to be expanded to 3D approaches, integrating the vertical habitat compression of marine organisms as a result of ocean warming and deoxygenation, as climate velocities for temperature and oxygen have contrasting vertical and horizontal patterns. There is a need for regional biogeochemical-coupled modelling studies dedicated to the Chilean islands in order to provide an integrated view of the impact of anthropogenic stressors (e.g. deoxygenation, increased stratification, and climate shift) at the scale required for addressing socio-ecological interactions. A refined understanding of the large-scale biogeography and spatial dynamics of marine populations through experimentation with high-resolution regional ocean models is a prerequisite for scaling-up regional management planning and optimizing the conservation of interconnected marine ecosystems across large scales.