A measure of near‐surface fluid motions that predicts air‐water gas transfer in a wide range of conditions
A measure of near‐surface fluid motions that predicts air‐water gas transfer in a wide range of conditions
复制标题
近地表流体运动的测量，可预测各种条件下的空气-水气体传递
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
Sanjoy Banerjee
中科院分区：
文献类型：
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作者：
D. Turney;W. Smith;Sanjoy Banerjee
气水气体传输影响许多重要的地球化学过程，但目前的理解涉及很大的不确定性。这是因为该过程依赖于分子扩散和流体运动之间的复杂相互作用，而这种相互作用尚未得到充分表征。在这里，我们展示了一个机制模型的第一个实验支持，该模型将近地表运动与一系列风况下的气体传输系数联系起来，包括那些导致破碎小波的因素。我们发现，均方根表面速度发散的平方根与理论预测的气体传递系数以及均方表面斜率呈线性变化。除了促进对空气-水气体传输机制的理解外，这些结果还提出了易于测量的参数，这些参数可以通过进一步研究提供现场设置中的气体传输系数。
Air‐water gas transfer impacts many important biogeochemical processes, yet current understandings involve large uncertainty. This arises because the process depends on a complex interaction between molecular diffusion and fluid motions that has not been adequately characterized. Here we show the first experimental support for a mechanistic model that relates near‐surface motions to gas transfer coefficients over a range of wind conditions, including those leading to breaking wavelets. We find that the square root of the root mean square surface‐velocity divergence varies linearly with both the gas transfer coefficient, as predicted by theory, as well as with mean square surface slope. Besides advancing the understanding of the mechanisms governing air‐water gas transfer, these results suggest easy‐to‐measure parameters that could, with further investigation, provide gas transfer coefficients in field settings.