Coarsening of soil properties and topography for large scale fully coupled subsurface-land-atmosphere models

项目P5的目的是在研究单位的耦合数据同化框架中表示土壤，并研究土壤在耦合模式中的多变量数据同化中的作用。在第一阶段，土壤被考虑在米的长度尺度上，并与其他隔室分离。在第二阶段，该项目开发了用完全耦合系统的粗网格单元处理非饱和区中的流动的方法。该项目将研究如何在完全耦合的数据同化模式中表示土壤，当观测量不同于土壤和土地利用结构平滑的大模式网格体积时。在其他与观测和模型之间的比例差距有关的问题中，该项目将解决粗化地形时处理山坡的问题。另一个重点将是土壤观测同化对地下水和大气等其他分区的影响，以及其他分区中的观测对土壤状态变量和通量的模型预测的影响。这将在与项目伙伴合作的多变量数据同化实验中完成。

This project P5 aims at the representation of soils in the coupled data assimilation framework of the research unit and at the role of soils in multivariate data assimilation in coupled models. In Phase I, soils were considered on length scales of meters and decoupled from the other compartments. In Phase II, the project develops methods to treat flow in the unsaturated zone with coarse grid cells of a fully coupled system. The project will investigate, how to represent soils in the fully coupled data assimilation model, when observation volumes differ from large model grid volumes with soil and land use structure smoothed out. Amongst other problems related to the scale gap between observations and model, the project will address the treatment of hillslopes when coarsening topography. Another focus will be the impact of the assimilation of soil observations on the other compartments such as the groundwater and the atmosphere and the impact of observation in other compartments on model predictions of state variables and fluxes in soils. This will be done in multivariate data assimilation experiments in collaboration with project partners.