Integrated surface-subsurface hydrologic modelling of fluid flow, solute and thermal transport

地下水和地表水系统中污染物或热能的流动和扩散模式受到水力参数、多组分化学反应过程和大气输入的空间变异性的强烈影响。在地表和地下流动机制内在耦合的背景下，设计用于预测陆地、河流和变饱和地下流速以及污染物和热能交换通量的现实计算模型还必须适应复杂的地形、土地利用/土地覆盖的时空变化以及幕式或长期强迫函数，所有这些都是在次流域到流域到大陆的三维尺度上进行的。我最近在解决涉及强耦合系统的问题的计算水文地质学/水文学方面取得了长足的进步，这使我们能够以前所未有的3D细节在数百到数千平方公里甚至更远的范围内探索许多突出的问题。为了深入了解非均匀地表/地下流动系统中大气/地表/地下交换过程的行为，将对地表水和地下水科学家面临的各种当代问题进行高分辨率数值模拟，包括对监测良好的流域的模型应用。拟议的研究将集中在水量和水质问题上。我的研究小组一直在积极开发和应用新的三维数值解决策略，以解决高度非线性的偏微分方程，描述流体流动，质量和热传输在一个集成的表面/地下建模框架。我们的三维完全集成的地表/地下水文地球圈模型是最先进的，被科学界广泛使用。由于现有的气候模型不能代表饱和区地下水流动的动态、陆地表面水入渗/渗漏的复杂模式以及河流、湿地和水体之间地下水相互作用的相关模式，因此正在将水文地球圈的平行版本与几个知名的气候模型进行完全耦合。

Fluid flow and spreading patterns of contaminants or thermal energy in groundwater and surface water systems are strongly influenced by the spatial variability of hydraulic parameters, multi-component chemical reaction processes and atmospheric inputs. In the context of surface and subsurface flow regimes, which are inherently coupled, realistic computational models designed to predict overland, stream and variably-saturated subsurface flow rates and contaminant and thermal energy exchange fluxes must also accommodate complex topography, spatial and temporal variations in land use/land cover and episodic or long-term forcing functions, all at the sub-watershed to watershed to continental scales in three dimensions. My recent strides in computational hydrogeology/hydrology to address problems involving strongly coupled systems have uniquely positioned us to explore many of the salient issues at hand in unprecedented detail in 3D at scales ranging from hundreds to thousands of square kilometres and beyond. In order to gain insight into the behaviour of atmospheric/surface/subsurface exchange processes in heterogeneous surface/subsurface flow systems, high-resolution numerical simulations of a variety of contemporary problems facing surface water and groundwater scientists, including model applications to well-monitored watersheds, will be performed. The proposed research will focus on both water quantity and quality issues. My research group has been actively developing and applying new 3D numerical solution strategies to solve the highly nonlinear partial differential equations describing fluid flow, mass and heat transport in an integrated surface/subsurface modelling framework. Our 3D fully-integrated surface/subsurface model HydroGeoSphere is state-of-the-art and is widely used by the scientific community. Full coupling of a parallel version of HydroGeoSphere to several well-known climate models is being performed because existing climate models fail to represent the dynamics of saturated-zone groundwater flow and the complex patterns of water infiltration/exfiltration over the land surface and related groundwater interactions between streams, wetlands and water bodies.