全球风暴浪潮模型对海面拖拉力的敏感性
Feyza Nur Özkan1, Martin Verlaan1,2, Sanne Muis2,3
1Delft Institute of Applied Mathematics, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands.
概括
先进的海面阻力参数化通过减少对最大潮值的低估,显著改善了风暴潮预测. 实现动态,波动依赖的粗度,特别是变量Charnock,对于准确的沿海洪水预测至关重要.
科学领域:
- 海洋学 海洋学 海洋学
- 气象学 天气学
- 沿海工程 沿海工程
背景情况:
- 准确的风暴潮模型对于沿海洪水预测和减轻影响至关重要.
- 现有的模型往往难以准确预测极端冲浪事件.
研究的目的:
- 评估各种海面阻力参数对风暴潮预测的影响.
- 确定最有效的拖动配方,以提高模型的准确性.
主要方法:
- 利用全球潮和浪潮模型 (GTSM) 进行10年时间和两个特定风暴事件的模拟.
- 我们比较了四个模型实验:一个完全动态的配方与简化的恒 drag 方法.
- 研究了可变空气密度,大气稳定性和海洋状态依赖的阻力的影响.
主要成果:
- 先进的阻力配方将全球低估的年度最大激增从18%降低到12%,其中变量Charnock是最有效的.
- 波浪依赖的粗度改善了Storm Xaver (RMSE从0.21米减少到0.16米) 和风Fiona (改善了高达0.30米) 的冲浪预测.
- 空气密度和大气稳定的变化对冲浪高度的影响最小.
结论:
- 动态的,取决于海洋状态的阻力配方,特别是变量Charnock,是提高风暴潮预测准确性的关键.
- 虽然有所改善,但对极端激增事件的持续低估仍然是一个挑战.
- 波浪依赖的粗度在高度和风暴易发的地区,海平面变化的地区显示出特别的好处.
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