“…However, as a result of simplification, this approach has the potential to produce significant errors, or deviations, from the complex model. Although there are newly emerging projection-based techniques for producing extremely accurate low-fidelity models, such as proper orthogonal decomposition (Gosses et al, 2018;Ushijima & Yeh, 2017;Siade et al, 2010Siade et al, , 2012 and dynamic mode decomposition (Schmid, 2010), these methods are mainly limited to linear, well-behaved models and likely infeasible for real-world models involving complex, nonlinear, discontinuous boundary conditions and processes. The second, data-driven, category aims to develop some kind of empirical surrogate model that approximates the input-output relationships of the complex model.…”