Sea-level rise enhances carbon accumulation in United States tidal wetlands

•Relative sea-level rise is the dominant driver of coastal wetland carbon accumulation•Balances between soil growth and erosion determine landscape-scale budgets•Even submerging marshes sequester at rates that increase with Coastal wetlands are well-known hotspots for sequestration. However, they vulnerable to rise, there concern this important sink may weaken under climate change. We synthesized 503 measurements accumulation from across United States show positively correlated local rise. then examined rapidly Louisiana coast investigate balance loss in eroding gain surviving marshes. find generally fastest portions where land highest, allowing a net persist. Although will eventually lead loss, our results suggest strong negative carbon-climate feedback marshes, even accumulate more efficiently than terrestrial systems, but potentially threatens persistence prominent sink. 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