Guillaume Jouvet, Guillaume Cordonnier

Convolutional Neural Networks (CNN) trained from high-order ice flow model realizations have proven to be outstanding emulators in terms of fidelity and computational performance. However, the dependence on an ensemble of realizations of an instructor model renders this strategy difficult to generalize to a variety of ice flow regimes found in the nature. To overcome this issue, we adopt the approach of physics-informed deep learning, which fuses traditional numerical solutions by finite differences/elements and deep learning approaches. Here, we train a CNN to minimise the energy associated with high-order ice flow equations within the time iterations of a glacier evolution model. As a result, our emulator is a promising alternative to traditional solvers thanks to its high computational efficiency (especially on GPU), its high fidelity to the original model, its simplified training (without requiring any data), its capability to handle a variety of ice flow regimes and memorize previous solutions, and its relative simple implementation. Embedded into the ``Instructed Glacier Model’’ (IGM) framework, the potential of the emulator is illustrated with three applications including a large-scale high-resolution (2400x4000) forward glacier evolution model, an inverse modelling case for data assimilation, and an ice shelf.