Coral reef islands can accrete vertically in response to sea level rise.
Coral reef islands can accrete vertically in response to sea level rise.
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珊瑚礁岛屿可以随着海平面上升而垂直增生。
DOI：
10.1126/sciadv.aay3656
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发表时间：
2020
期刊：
影响因子：
13.6
通讯作者：
Masselink G
中科院分区：
文献类型：
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作者：
Masselink G
由于海平面上升（SLR）造成的洪水增加预计将使珊瑚礁岛屿（定义为珊瑚礁平台顶部的桑迪或砾石岛屿）在几十年内无法居住。这种预测一般假定礁岛是地质惰性地貌，无法调整形态。我们提出的数值模拟结果表明，由砾石材料组成的礁岛是形态动力学弹性地貌，SLR下的增生，以保持积极的干舷，同时撤退lagoonwards的发展。这种岛屿调整是由将沉积物从海滩表面转移到岛屿表面的波浪越顶过程驱动的。我们的研究结果表明，珊瑚礁岛屿的这种自然适应可能会提供一个替代的未来轨迹，可能会支持一些岛屿的短期可居住性，尽管有额外的管理挑战。在一个给定的礁岛SLR脆弱性的充分表征应结合联合收割机形态动力学模型与气候相关的影响淡水供应，碳酸盐沉积物供应和未来的波浪制度的评估。
Increased flooding due to sea level rise (SLR) is expected to render reef islands, defined as sandy or gravel islands on top of coral reef platforms, uninhabitable within decades. Such projections generally assume that reef islands are geologically inert landforms unable to adjust morphologically. We present numerical modeling results that show reef islands composed of gravel material are morphodynamically resilient landforms that evolve under SLR by accreting to maintain positive freeboard while retreating lagoonward. Such island adjustment is driven by wave overtopping processes transferring sediment from the beachface to the island surface. Our results indicate that such natural adaptation of reef islands may provide an alternative future trajectory that can potentially support near-term habitability on some islands, albeit with additional management challenges. Full characterization of SLR vulnerability at a given reef island should combine morphodynamic models with assessments of climate-related impacts on freshwater supplies, carbonate sediment supply, and future wave regimes.