A downscaling scheme for atmospheric variables to drive soil–vegetation–atmosphere transfer models
A downscaling scheme for atmospheric variables to drive soil–vegetation–atmosphere transfer models
复制标题
驱动土壤-植被-大气转移模型的大气变量降尺度方案
DOI：
10.1111/j.1600-0889.2010.00466.x
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
C. Simmer
中科院分区：
文献类型：
--
作者：
A. Schomburg;V. Venema;R. Lindau;F. Ament;C. Simmer
为了驱动土壤植被迁移模型或水文模型，需要高分辨率的大气强迫数据。对于大多数应用，大气模式输出的分辨率太粗糙。为了避免非线性过程造成的偏差，降尺度系统应该预测大气强迫的未解决的变化。为此，我们推导出一个分解系统，包括三个步骤：（1）低分辨率数据的双二次样条插值，（2）所谓的“确定性”部分，基于高分辨率表面变量和所需的大气近地表变量之间的统计规则和（3）自回归噪声生成步骤。在高分辨率模式输出（水平网格间距400 m）的基础上，开发了解集系统，并对解集系统进行了测试。当应用到大气COSMO模式的最低层的大气变量，解聚是能够充分重建的参考字段。应用缩减步骤1和2，均方根误差减小。步骤3最终导致子网格的变化性和时间自相关与参考字段的密切匹配。该方案可以应用于大气模式的输出，无论是独立的离线模拟，和一个完全耦合的模型系统。
For driving soil–vegetation–transfer models or hydrological models, high-resolution atmospheric forcing data is needed. For most applications the resolution of atmospheric model output is too coarse. To avoid biases due to the non-linear processes, a downscaling system should predict the unresolved variability of the atmospheric forcing. For this purpose we derived a disaggregation system consisting of three steps: (1) a bi-quadratic spline-interpolation of the low-resolution data, (2) a so-called ‘deterministic’ part, based on statistical rules between high-resolution surface variables and the desired atmospheric near-surface variables and (3) an autoregressive noise-generation step. The disaggregation system has been developed and tested based on high-resolution model output (400mhorizontal grid spacing).Anovel automatic search-algorithm has been developed for deriving the deterministic downscaling rules of step 2. When applied to the atmospheric variables of the lowest layer of the atmospheric COSMO-model, the disaggregation is able to adequately reconstruct the reference fields. Applying downscaling step 1 and 2, root mean square errors are decreased. Step 3 finally leads to a close match of the subgrid variability and temporal autocorrelation with the reference fields. The scheme can be applied to the output of atmospheric models, both for stand-alone offline simulations, and a fully coupled model system.
影响因子：
8.9
作者：
Venema;S. Gimeno García;C. Simmer
通讯作者：
C. Simmer