Sfyri Eleni, Rotach Mathias W, Stiperski Ivana, Bosveld Fred C, Lehner Manuela, Obleitner Friedrich
1Department of Atmospheric and Cryospheric Sciences, University of Innsbruck, Innrain 52f, 6020 Innsbruck, Austria.
2Royal Netherlands Meteorological Institute, 3701 AE De Bilt, The Netherlands.
Boundary Layer Meteorol. 2018;169(1):11-46. doi: 10.1007/s10546-018-0365-3. Epub 2018 Jun 14.
The scaled standard deviations of temperature and humidity are investigated in complex terrain. The study area is a steep Alpine valley, with six measurement sites of different slope, orientation and roughness (i-Box experimental site, Inn Valley, Austria). Examined here are several assumptions forming the basis of Monin-Obukhov similarity theory (MOST), including constant turbulence fluxes with height and the degree of self-correlation between the involved turbulence variables. Since the basic assumptions for the applicability of the MOST approach-horizontally homogeneous and flat conditions-are violated, the analysis is performed based on a local similarity hypothesis. The scaled standard deviations as a function of local stability are compared with previous studies from horizontally homogeneous and flat terrain, horizontally inhomogeneous and flat terrain, weakly inhomogeneous and flat terrain, as well as complex terrain. As a reference, similarity relations for unstable and stable conditions are evaluated using turbulence data from the weakly inhomogeneous and flat terrain of the Cabauw experimental site in the Netherlands, and assessed with the same post-processing method as the i-Box data. Significant differences from the reference curve and also among the i-Box sites are noted, especially for data derived from the i-Box sites with steep slopes. These differences concern the slope and the magnitude of the best-fit curves, illustrating the site dependence of any similarity theory.
在复杂地形中研究了温度和湿度的尺度化标准差。研究区域是一个陡峭的高山峡谷，有六个不同坡度、方向和粗糙度的测量站点（i-Box实验站点，奥地利因河谷）。这里检验了构成莫宁-奥布霍夫相似性理论（MOST）基础的几个假设，包括湍流通量随高度恒定以及相关湍流变量之间的自相关程度。由于MOST方法适用的基本假设——水平均匀和平坦条件——被违反，因此基于局部相似性假设进行分析。将作为局部稳定性函数的尺度化标准差与先前在水平均匀平坦地形、水平非均匀平坦地形、弱非均匀平坦地形以及复杂地形中的研究结果进行了比较。作为参考，使用来自荷兰卡堡实验站点弱非均匀平坦地形的湍流数据评估了不稳定和稳定条件下的相似关系，并采用与i-Box数据相同的后处理方法进行评估。注意到与参考曲线以及i-Box站点之间存在显著差异，特别是对于来自陡坡i-Box站点的数据。这些差异涉及最佳拟合曲线的斜率和幅度，说明了任何相似性理论对站点的依赖性。
