A model of the weathering crust and microbial activity on an ice-sheet surface

Abstract. Shortwave radiation penetrating beneath an ice-sheet surface can cause internal melting and the formation of a near-surface porous layer known as weathering crust, dynamic hydrological system that provides home to impurities microbial life. We develop mathematical model, incorporating thermodynamics population dynamics, for evolution such layers. The model accounts conservation mass energy, surface-absorbed radiation, logistic growth species mediated by nutrients are sourced from ice. It also potential melt–albedo microbe–albedo feedbacks, through dependence absorption coefficient on porosity or concentration. investigate one-dimensional steadily solutions which give rise predictions crust depth, water content, melt rate, abundance, depending number parameters. In particular, we examine how these quantities depend forcing energy fluxes, finding relative amounts shortwave (surface-penetrating) other heat fluxes particularly important in determining structure crust. results explain why crusts form disappear under different conditions suggest range possible changes behaviour response climate change.