Future Physical and Biogeochemical Ocean Conditions under Climate Change along the British Columbia Continental Margin

Climate change impacts coastal ecosystems through large scale changes in temperature, stratification, circulation and ocean acidification. Here, the potential response of British Columbia continental margin to climate is investigated using a regional circulation-biogeochemical model downscale projections from Canadian global models (CanRCM4/CanESM2) under two Intergovernmental Panel on Change emission scenarios (RCP 4.5 RCP 8.5). Projections future physical biogeochemical conditions for 2041–2070 period are compared recent past (1981–2010). We found an overall annual average warming >1.6°C sea surface increase stratification upper layer, decrease pH as much 0.21. Increasing changing winds have limited impact nitrate availability, phytoplankton biomass primary production, whilst increases production by up 30% most domain. Increased atmospheric CO2 contributes acidification over domain with aragonite saturation (Ωarag) at all depths resulting 20 32% volume Ωarag ≤1 100 m shelf depending scenario. Our projected results, therefore, show that may alter amount food available higher trophic levels habitat benthic species, since bottom waters will be undersaturated respect 2–3 months mid-summer. Both results similar pattern but were stronger more extensive 8.5 showing benefit mitigation efforts reducing effect marine ecosystem stressors.