Value of Groundwater Data in the Assimilation of the Groundwater-Soil-Land-Surface Nexus

该项目研究了(a)地下水观测和含水层性质估计是否以及如何通过大气-地表-地下耦合系统的数据同化改善总体状态估计和预测，以及(b)相邻隔间的状态和性质更新是否以及如何改善地下水隔间的状态估计。我们期望通过在耦合建模框架内对所有相邻隔层跨越含水层边界的通量进行一致处理来增加价值。然而，合并相邻的隔间增加了计算工作量，除了隔间之间的空间和时间尺度不匹配之外，还增加了概念和参数的不确定性。该项目将在基于TerrSysMP-PDAF的弱耦合和强耦合数据同化框架中制定更新地下水状态和参数的最佳策略。

The project investigates (a) whether and how groundwater observations and the estimation of aquifer properties improve the overall state estimation and prediction by data assimilation in coupled atmosphere-surface-subsurface systems, and (b) whether and how updating states and properties of neighbouring compartments improves the state estimation of the groundwater compartment. We expect added value by a consistent treatment of fluxes across aquifer boundaries in all neighbouring compartments within a coupled modeling framework. However, incorporating neighbouring compartments increases computational efforts, and adds conceptual and parametric uncertainty besides mismatching spatial and temporal scales between the compartments. The project will develop the best strategy for updating groundwater states and parameters both in a weakly and strongly coupled data assimilation framework based on TerrSysMP-PDAF.