Field estimates of scalar advection across a canopy edge
Field estimates of scalar advection across a canopy edge
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DOI：
10.1016/j.agrformet.2011.01.003
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发表时间：
2011-05
影响因子：
6.2
通讯作者：
J. Kochendorfer;U. KyawThaPaw
中科院分区：
文献类型：
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作者：
J. Kochendorfer;U. KyawThaPaw
在平坦均匀地形的理想情况下，在作物冠层边缘和下风向测量能量和质量的水平和垂直通量，以研究非均匀性对地气交换的影响。能量平衡关闭也进行了检查和经常被忽视的平流项上的能量收支的影响进行了评估。结果表明，无论是垂直或水平平流不应被忽略，从非均匀边界的中等距离下风，与能量收支关闭附近的前缘改善了20%以上的水平和垂直平流的潜热和感热。即使在典型的白天条件下，水汽和温度的平均平流水平和垂直通量的显着分歧。在稳定的条件下，水平平流可以负责超过15%的标量（水蒸气）运输136冠层高度的水蒸气源密度和表面粗糙度的变化顺风。
Measurements of the horizontal and vertical fluxes of energy and mass were taken at a crop canopy edge and downwind of it to examine the effects of inhomogeneity on surface–atmosphere exchange, for the ideal case of flat uniform terrain. Energy balance closure was also examined and the effects of the often-neglected advection terms on the energy budget were evaluated. The results show that neither vertical nor horizontal advection should be neglected for moderate distances downwind from heterogeneous boundaries, with the energy budget closure near the leading edge improved by more than 20% with the inclusion of the horizontal and vertical advection of latent and sensible heat. Significant mean advective horizontal and vertical flux divergences of water vapor and temperature were found even in typical daytime conditions. In stable conditions horizontal advection can be responsible for more than 15% of the scalar (water vapor) transport 136 canopy heights downwind of a change in water vapor source density and surface roughness.