Work

Simulating the effect of natural convection in a tundra snow cover

Year: 2026

Type: article

Abstract: . As a straightforward solution to improve the one-dimensional physics-based multi-layer snow model SNOWPACK, a C++ interface is implemented for a tight coupling between SNOWPACK and OpenFOAM with the aim to investigate natural convection in real snow covers. OpenFOAM simulates convection in two dimensions based on SNOWPACK snow profiles and feeds the convective vapor fluxes back to SNOWPACK. Among different snow covers, significant convection events that are well synchronized with cold events are numerically observed by the SNOWPACK-OpenFOAM coupler for a herb tundra permafrost at Bylot Island only if we neglect wind slab formation for surface layers. We find significant sublimation in downward flow regions and that convection generates a low-density path extending vertically almost through the whole snow column. The strong footprint of convection on snow density and temperature with significant lateral variations up to 90 kg m−3 and 5 K respectively makes a consistent representation in the SNOWPACK one-dimensional profile difficult. But the most prominent effect of convection on the snow density profile, namely a low density foot and high density top, corresponds qualitatively to observations. Further work is required to adapt physical parameterizations in conventional snow models to represent this effect and its interaction with snow settling and metamorphism.

Source: The cryosphere

DOI: 10.5194/tc-20-2439-2026

Authors: Mahdi Jafari, Michael Lehning

Institutions: École Polytechnique Fédérale de Lausanne, WSL Institute for Snow and Avalanche Research SLF

Language: English

Topic: Cryospheric studies and observations

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $1,574