一般化风型模型在山区森林中的适用性
Yun-Chao Pang1,2,3, Tian Gao2,4,5, Xiu-Fen Li1,2,4
1Shenyang Agricultural University, Shenyang 110866, China.
Ying yong sheng tai xue bao = The journal of applied ecology
|April 22, 2024
概括
莫宁-奥布霍夫风形状模型对于复杂的地形是不准确的,高估了风速,需要改进流量模型. 它只在平面上表现良好.
科学领域:
- 大气科学 大气科学
- 环境科学 环境科学
- 地质物理学 地质物理学
背景情况:
- 莫宁-奥布霍夫 (M-O) 相似性理论提供了一个广泛用于预测平面地形上风速的风形方程.
- 它在复杂地形上的适用性和准确性,对于估计空气动力学参数至关重要,例如零位移高度 (d) 和粗度长度 (z),仍然在很大程度上未得到验证.
- 准确的空气动力学参数估计对于使用诸如旋转协变等方法进行流量计算 (碳,水,微量气体) 是至关重要的.
研究的目的:
- 评估基于M-O相似性理论的通用风形状模型在复杂的山地地形中的适用性.
- 将模型在复杂地形中的性能与在平坦的农业景观中的性能进行比较.
- 确定影响不同地形和季节风形状模型准确性的主要因素.
主要方法:
- 在清远森林CERN (复杂地形) 的一个流域中使用三个流量塔收集了三维风速数据.
- 来自复杂地形站点的数据与来自潘金农业站 (平坦地形) 的数据进行了比较.
- 统计分析,包括确定系数 (R2),标准误差和F测试,用于评估模型性能.
主要成果:
- 基于M-O的风形状模型显著低估了复杂地形中的风速,R2值在0.12和0.30之间.
- 在复杂的地形中预测的风速被大大高估,有时是两倍,标准误差高达2m·s-1.1.
- 相比之下,该模型在平坦的农业景观中准确预测了风速 (R2:0.900.93,标准误差:0.5 m·s-1).
结论:
- 一般化的风形状模型不适合预测复杂地形中的风速,特别是森林树冠上的风速.
- 在复杂地形中低估零位移高度 (d) 和粗度长度 (z) 会导致空气动力学高度估计不准确.
- 地形复杂性是限制模型适用性的主要因素,季节性 (上/下叶) 是次要影响因素.
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