Grant: Alliance Grants

Climate change is rapidly altering the planet, and solutions are urgently required to reduce greenhouse gas (GHG) emissions and limit further warming. In 2021, Canada committed to more ambitious greenhouse gas (GHG) emissions-reductions targets to mitigate climate change. Achieving these new targets will require an accounting of all mitigation options, including Canada's natural ocean carbon sinks. Blue carbon ecosystems (BCE; salt marshes, seagrass meadows, and potentially kelp forests) and marine soft sediment habitats are increasingly recognized as important carbon reservoirs. Yet, despite having the world's longest coastline, Canada has yet to account for ocean carbon sinks in its GHG inventories. Our proposed partnership research with DFO, Parks Canada, BC Parks, Oceans North, The Kelp Rescue Initiative, Nature Trust, BC Parks, and the Ecology Action Centre will produce the critically-needed nationwide assessment of the potential for Canada's oceans to contribute to natural climate solutions (NCS). Together we will: 1) quantify the current and future (projected to 2050) annual mitigation potential of coastal blue carbon ecosystems using species distribution models (SDMs) coupled with carbon sequestration rates. SDMs will incorporate Canada-wide syntheses of all available occurrence records for salt marsh, seagrass, and kelp, and be informed by state-of-the-art dynamically-downscaled ocean hydrography data sets and IPCC climate projections tailor-made for Canada's Arctic, Atlantic and Pacific nearshore coastlines; 2) quantify the marine soft-sediment carbon sinks that could be preserved by limiting Canada's bottom-trawl footprint; 3) evaluate the areas of Canada's coastlines where protection or restoration would provide the greatest NCS benefits. This partnership will significantly advance scientific understanding of the extent to which Canada's ocean carbon sinks can contribute to emissions reductions, and enable inclusion of these sources in our climate mitigation accounting. Our research will also enable evaluation of the climate change benefits of existing protected marine areas, and identify important areas that could be prioritized for future spatial protection.