Evaluating the Current and Future Capacity for Natural Climate Solutions in Canada's Oceans

气候变化正在迅速改变地球，迫切需要解决方案来减少温室气体（GHG）排放并限制进一步变暖。2021年，加拿大承诺制定更加雄心勃勃的温室气体（GHG）减排目标，以减缓气候变化。要实现这些新目标，就需要对包括加拿大天然海洋碳汇在内的所有缓解方案进行核算。蓝碳生态系统（BCE；盐沼、海草草甸和潜在的海带林）和海洋软沉积物栖息地越来越被认为是重要的碳库。然而，尽管拥有世界上最长的海岸线，加拿大尚未将海洋碳汇计入其温室气体清单。我们提议与DFO、加拿大公园、BC公园、海洋北部、海带救援倡议、自然信托、BC公园和生态行动中心进行合作研究，将对加拿大海洋为自然气候解决方案（NCS）做出贡献的潜力进行迫切需要的全国性评估。我们将共同：1)利用物种分布模型（SDMs）和碳固存率，量化目前和未来（预计到2050年）沿海蓝碳生态系统的年度减缓潜力。SDMs将在加拿大范围内综合所有可用的盐沼、海草和海带的发生记录，并通过最先进的动态缩小的海洋水文数据集和为加拿大北极、大西洋和太平洋近岸海岸线量身定制的IPCC气候预测提供信息；2)量化通过限制加拿大底拖网足迹可以保存的海洋软沉积物碳汇；3)评估加拿大海岸线的保护或恢复将提供最大的NCS利益的地区。这一伙伴关系将大大促进对加拿大海洋碳汇能够在多大程度上促进减排的科学理解，并使我们能够将这些来源纳入我们的气候缓解核算。我们的研究还将有助于评估现有海洋保护区的气候变化效益，并确定未来可能优先进行空间保护的重要区域。

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.