Currents and convection cause enhanced gas exchange in the ice–water boundary layer
Currents and convection cause enhanced gas exchange in the ice–water boundary layer
复制标题
洋流和对流导致冰水边界层中的气体交换增强
DOI：
10.3402/tellusb.v68.32803
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
D. Perovich
中科院分区：
文献类型：
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作者：
B. Loose;A. Lovely;P. Schlosser;C. Zappa;W. McGillis;D. Perovich
海冰的存在是海气交换的物理障碍。另一方面，由于冰形成过程中的水流剪切和对流，它会产生额外的湍流。我们目前的结果，从实验室研究，演示如何剪切和对流在冰海洋边界层可以导致显着的气体交换。在没有风的情况下，冰下0.23 m s − 1的水流产生2.8 m d − 1的气体传输速度（k），相当于在公海上7 m s − 1的风速产生的k。由海气热交换引起的对流也使k值比单独由海流切变产生的k值增加了131%。当风和海流结合时，k增加到7.6 m d − 1，大于风或海流单独产生的k，但在这些实验中，风强迫的气体交换产生了混合的结果。总的来说，这些实验表明，使用风速参数化来估计海冰区的k可能会低估k约。风速<8 m s − 1时为50%。
The presence of sea ice acts as a physical barrier for air–sea exchange. On the other hand it creates additional turbulence due to current shear and convection during ice formation. We present results from a laboratory study that demonstrate how shear and convection in the ice–ocean boundary layer can lead to significant gas exchange. In the absence of wind, water currents beneath the ice of 0.23 m s−1 produced a gas transfer velocity (k) of 2.8 m d−1, equivalent to k produced by a wind speed of 7 m s−1 over the open ocean. Convection caused by air–sea heat exchange also increased k of as much as 131 % compared to k produced by current shear alone. When wind and currents were combined, k increased, up to 7.6 m d−1, greater than k produced by wind or currents alone, but gas exchange forcing by wind produced mixed results in these experiments. As an aggregate, these experiments indicate that using a wind speed parametrisation to estimate k in the sea ice zone may underestimate k by ca. 50 % for wind speeds <8 m s−1.