在几内亚湾的海平面变化从卫星高度测量
Franck Eitel Kemgang Ghomsi1,2,3, Roshin P Raj4, Antonio Bonaduce4
1Department of Oceanography, University of Cape Town, Cape Town, South Africa. franckeitel@gmail.com.
Scientific reports
|February 27, 2024
概括
几内亚湾的沿海海平面上升正在加速,从1993年到2021年,平均海平面上升了8.9厘米. 了解这些变化和相关的极端事件对于沿海的弹性至关重要.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 沿海地理形态学沿海地理形态学
背景情况:
- 沿海地区,特别是几内亚湾 (GoG),面临着气候变化影响的重大风险,例如海平面上升和洪水.
- 印度政府的潮测量数据有限,这阻碍了对沿海海平面十年变化的理解.
- 卫星高度测量为在数据稀缺的地区监测海平面变化提供了有价值的工具.
研究的目的:
- 调查赤道大西洋海平面变化与几内亚湾沿海之间的联系.
- 通过使用卫星高度测量数据,量化GOG海平面上升的速度和加速.
- 分析与该地区极端气候事件相关的沿海被困波 (CTW) 的驱动因素和传播.
主要方法:
- 利用近三十年 (1993-2021) 的卫星高度测量数据.
- 综合的海面温度异常,PIRATA停泊数据 (20°C异热),以及基于Argo的立体/温度海平面数据.
- 分析了沿海被困波 (CTW) 的传播及其与大西洋尼诺现象的相关性.
主要成果:
- 印度群岛的平均海平面上升率从3.47mm/年增加到3.89mm/年,加快了0.094mm/年2.2.
- 在1993年至2021年期间,海平面上升总量约为8.9厘米.
- 确定CTW从赤道到西非海岸的传播延迟1个月,与2010年,2012年,2019年和2021年的极端变暖事件有关.
结论:
- 该研究量化了几内亚湾海平面上升和加速的显著程度,突出了其脆弱性.
- 了解沿海被困波浪的动态及其与极端事件的联系对于预测和管理沿海影响至关重要.
- 调查结果强调了持续研究的必要性,以支持知情决策和加强沿海社区应对气候变化的弹性.
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