Processes shaping forest snow cover evolution often vary at small spatial scales, which are not resolved by most model applications. Representing this variability at larger scales and coarser model resolutions constitutes a major challenge for model developers. In this study, we use a well‐validated hyper‐resolution forest snow model that explicitly resolves the spatial variability of canopy‐snow interactions at the meter scale to explore adequate representation of forest‐snow processes at coarser resolutions (50 m). For this purpose, we assess coarser‐resolution runs against spatially averaged results from corresponding hyper‐resolution simulations over a 150,000 m² model domain. For the coarser‐resolution simulations, we tested alternative upscaling strategies. Our results reveal considerable discrepancies between strategies that utilize generalized canopy metrics versus strategies that apply a more detailed set of process‐specific canopy descriptors. Particularly, the inclusion of canopy descriptors that represent the various scales and perspectives relevant to the individual processes leads to accurate simulation of forest snow cover dynamics at coarse resolutions. Our results further demonstrate that a realistic representation of snow‐covered fraction in snowmelt calculations is important even for relatively small (∼50 m) grid cells. Ultimately, this work provides recommendations for modeling forest‐snow processes in large‐scale applications, which allow coarse resolution simulations to approximate spatially averaged results of corresponding hyper‐resolution simulations.

中文翻译：

---

在粗分辨率模型中增加森林雪过程的物理表示：从升级超分辨率模拟中学到的经验教训

塑造森林积雪演变的过程通常在较小的空间尺度上变化，大多数模型应用无法解决这些问题。在更大的规模和更粗糙的模型分辨率下表现出这种可变性，对模型开发人员构成了重大挑战。在这项研究中，我们使用经过充分验证的超分辨率森林积雪模型，该模型明确解决了米尺度上的冠层-雪层相互作用的空间变异性，以探索在较粗分辨率（50 m）下森林-雪过程的适当表示。为此，我们根据150,000 m ^2上相应超分辨率模拟的空间平均结果，评估了较粗分辨率的运行模型域。对于较粗分辨率的模拟，我们测试了替代的放大策略。我们的结果表明，利用广义冠层度量的策略与应用更详细的过程特定冠层描述符集的策略之间存在很大差异。特别是，包含代表各个过程的各个尺度和观点的树冠描述符会导致以粗分辨率准确模拟森林积雪的动态。我们的结果进一步证明，即使对于相对较小（约50 m）的网格单元，在融雪计算中真实地表示积雪分数也很重要。最终，这项工作为在大型应用程序中对森林雪过程进行建模提供了建议，