沿海的硬化及其对世界沙的意义
Khin Nawarat1,2, Johan Reyns3,4, Michalis I Vousdoukas5
1Department of Coastal and Urban Risk & Resilience, IHE Delft Institute for Water Education, Delft, The Netherlands. k.nawarat@un-ihe.org.
Nature communications
|December 5, 2024
概括
世界上超过三分之一的沙海岸线已经变硬,这增加了海平面上升造成的严重海损失的脆弱性. 缓解努力可以在2100年前显著减少预计的海侵蚀.
科学领域:
- 沿海地质的地质学
- 环境科学环境科学
- 气候变化影响气候变化的影响.
背景情况:
- 海平面上升威胁低海拔沿海区域 (LECZ),影响生态系统和人类人口.
- 带有人造结构的沙面临着受限制的陆地迁移,容易受到侵蚀的影响.
- 硬化海岸线的全球规模及其严重海损失的风险仍然未得到量化.
研究的目的:
- 量化全球硬化沙海岸线的全球范围.
- 在不同的气候变化情景下评估严重海损失的风险.
- 确定最容易受到沿海侵蚀和海损失的影响的地区.
主要方法:
- 利用卫星图像产品和地理空间数据集来识别硬化的海岸线.
- 分析了政府间气候变化专门委员会 (IPCC) AR6区域的硬化海岸线范围.
- 整合了海岸硬化数据与海岸线退缩预测,以建模未来的海损失.
主要成果:
- 目前,世界上33%的沙海岸线已经变硬.
- 在高排放场景 (SSP5-8.5) 下,到2100年,多达26%的沙海岸线可能会遭受严重的海损失.
- 在温和排放情景下 (SSP2-4.5),严重的海损失预计将影响21%的沙海岸线.
- 预计高收入和中高收入国家将经历大多数严重的沙损失.
结论:
- 沿海的硬化显著加剧了由于海平面上升而造成严重海损失的风险.
- 未来海损失的程度对排放场景非常敏感,这凸显了气候变化减缓的重要性.
- 应对沿海侵蚀需要综合战略,考虑硬化和自然海岸线,重点关注脆弱的高收入国家和特定的IPCC地区.
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