“…But with the capabilities of the current generation of flow models, one is no longer restricted to the simulation of such simple GW systems anymore or forced to oversimplify more complex GW systems—the current trend is toward the simulation of complex systems based on integrated surface water (SW)‐GW flow models (IFMs; Barthel & Banzhaf, ; Paniconi & Putti, ). Compared to numerical models that exclusively simulate GW flow, IFMs enable the simulation of GW and SW flow in a physically‐based and fully‐coupled way and allow the inclusion of many hydrologically relevant processes such as unsaturated flow through complex heterogeneous structures (e.g., Irvine et al, ; Schilling, Irvine, et al, ; Tang et al, , ), heat and mass transport (e.g., Carniato et al, ; Karan et al, ; Kurtz et al, ; Schilling et al, ), snow accumulation, melt and pore water freeze‐thaw (e.g., Cochand et al, ; Evans & Ge, ; Painter et al, ; Schilling et al, ; Shojae Ghias et al, ), and SW‐GW‐vegetation interactions (e.g., Banks et al, ; Maxwell & Condon, ; Schomburg et al, ). Compared to numerical flow models that exclusively simulate GW flow, IFMs require more parameters and boundary conditions to be defined and calibrated (the minimally required parameters and boundary conditions of different types of GW and SW simulations are listed in Table ).…”