阻力系数依赖于北冰洋中部漂流海冰下边界层稳定性的阻力系数
Yusuke Kawaguchi1, Mario Hoppmann2, Kunio Shirasawa3
1Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Chiba, 277-8564, Japan. ykawaguchi@aori.u-tokyo.ac.jp.
Scientific reports
|July 4, 2024
概括
这项研究表明,冰洋阻力系数和转向角度随着稳定性而有显著变化. 这些发现表明,模拟中的常数参数值可能低估了冰块增长期间的北极电流.
科学领域:
- 海洋学 海洋学 海洋学
- 北极研究 北极研究
- 气候建模气候模型
背景情况:
- 冰洋阻力系数和转向角度对于合模拟中的动量转移至关重要.
- 当前的模型经常使用这些参数的常数值,忽略了冰洋界面稳定性.
研究的目的:
- 调查冰洋阻力系数和转向角度的变化.
- 确定静态稳定对这些关键参数的影响.
主要方法:
- 在北极中部的多年冰下直接观察热能和运动能平衡.
- 分析在从剥离到重新结的过渡过程中收集的数据.
主要成果:
- 观察到阻力系数 (1-130 x 10^-3) 和转角度 (-19-1°) 的显著变化.
- 显示了阻力系数对稳定性参数的强烈依赖,随着稳定性增加而迅速衰减.
- 发现转角度在不稳定的条件下较小,在稳定的条件下较大.
结论:
- 在中立/不稳定的条件下,冰到海洋的动量转移会增强,在稳定的条件下会减弱.
- 使用常量参数的数值模拟可能会低估北极冰增长时期的近地流.
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