资源环境科技发展态势分析平台

With Arctic amplification (enhanced polar warming) possibly increasing periods of intense winter freezing, and global warming producing more powerful extratropical storms, winter sedimentation on northern saltmarshes may likely increase in the future. Here we show that a large ice‐rafting event in northern MA delivered the equivalent of 15 years of mineral deposition to the marsh surface in a single storm. During an intense extratropical cyclone in January 2018, sediment laden ice was rafted onto the Great Marsh, MA, by a ~1m storm surge coinciding with high astronomical tides. The muddy sand content combined with abundant shells indicates that the sediment originated from proximal bays and tidal flats. Sediment layers delivered by individual ice rafts averaged 3.19 cm in thickness, 12 times the combined organic and inorganic yearly vertical accretion rate on high marshes. This previously under‐appreciated vector for sediment deposition is likely to help marsh resiliency to sea‐level rise (SLR).