Localized uplift, widespread subsidence and implications for sea level rise in the NYC Metropolitan Area

Regional relative sea level rise is exacerbating flooding hazards in the coastal zone. In addition to changes in the ocean, vertical land motion (VLM) is a driver of spatial variation in sea-level change that can either diminish or enhance flood risk. Here we apply state-of-the-art Interferometric Synthetic Aperture Radar (InSAR) and global navigation satellite system (GNSS) time-series analysis to estimate velocities and corresponding uncertainties at 30 m resolution in the New York City Metropolitan Area, revealing VLM with unprecedented detail. We find broad subsidence of 1.6 mm/yr consistent with glacial isostatic adjustment to the melting of the former ice sheets, and previously undocumented hotspots of both subsidence and uplift that can be physically explained in some locations. Our results inform ongoing efforts to adapt to sea-level rise and reveal points of VLM that motivate both future scientific investigations into surface geology and assessments of engineering projects.

区域相对海平面上升正在加剧沿海区域的洪涝灾害风险。除海洋自身变化外，垂直陆地运动（Vertical Land Motion, VLM）是造成海平面变化空间差异的驱动因子之一，其既可能降低也可能加剧洪涝风险。本研究采用当前最先进的合成孔径雷达干涉测量（Interferometric Synthetic Aperture Radar, InSAR）与全球导航卫星系统（Global Navigation Satellite System, GNSS）时序分析方法，以30米空间分辨率估算纽约都会区的垂直运动速率及其对应不确定性，以前所未有的精细程度揭示了垂直陆地运动的特征。研究发现，区域整体以1.6毫米/年的速率沉降，该现象与古冰盖消融引发的冰川均衡调整过程相符；同时还识别出此前未被记录的沉降与抬升热点区域，部分区域的异常运动可通过物理机制得到合理解释。本研究结果可为当前应对海平面上升的适应性工作提供科学参考，同时揭示的若干垂直陆地运动点位，可为后续地表地质相关科学研究以及工程项目评估提供明确的研究方向。