Snow equi-temperature metamorphism described by a phase-field model
applicable on micro-tomographic images: prediction of microstructural
and transport properties
Lisa Bouvet
Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France, Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France, Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France
Corresponding Author:[email protected]
Author ProfileNeige Calonne
Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France, Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France, Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France
Author ProfileFrederic Flin
Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France, Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France, Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Études de la Neige, 38000 Grenoble, France
Author ProfileChristian Geindreau
Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France, Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France, Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, Grenoble, France
Author ProfileAbstract
Representing snow equi-temperature metamorphism (ETM) is key to model
the evolution and properties of the snow cover. Recently, a phase-field
model describing mean curvature flow evolution on 3-D microstructures
was proposed (Bretin et al., 2019). In the present work, this model is
used to simulate snow ETM at the pore scale, considering the only
process of moving interfaces by sublimation-deposition driven by
curvatures. We take 3-D micro-tomographic images of snow as input in the
model and obtain a time series of simulated microstructures as output.
Relating the numerical time, as defined in the model, to the real
physical time involves the condensation coefficient, a
poorly-constrained parameter in literature. A calibration was performed
by fitting simulations to experimental data through the evolution of
specific surface area (SSA) of snow under ETM at -2°C. A value of the
condensation coefficient was obtained: (9.8 ± 0.7) 10-4 and was used in
all the following simulations. We then show that the calibrated model
enables to well reproduce an independent time series of ETM at -2°C in
terms of SSA, covariance length, and mean curvature distribution.
Finally, the calibrated model was used to investigate the effect of ETM
on microstructure and effective transport properties (thermal
conductivity, vapor diffusion, permeability), for four different
samples. As an interesting preliminary result, simulations show an
enhancement of the structural anisotropy of snow in the case of
initially anisotropic microstructures such as depth hoar. Results
highlight the potential of such micro-scale models for the development
of snow property predictions for large-scale snowpack models.