iSUBLIME · Isotopes in Sublimation by Laboratory and In-field Meteorological Experiments

Snow and ice influence the Earth’s hydrological cycle and radiation balance and therefore are prime factors governing the climate and water resources. Snow storage and ablation by melting and sublimation play a crucial role in numerous atmospheric, ecological, and ecosystem processes. While the processes related to the isotopic mass exchange during sublimation of snow are well understood, the parameterization of snow sublimation, which is critical to improving the predictive modelling of the fate of snow in the present and near future, remains an important problem to be addressed. The primary question of this project is: what are the key processes that control the patterns and magnitude of snow sublimation fluxes to the atmosphere? This question will be addressed through i) high temporal resolution measurements of snow properties, natural isotopic tracers, and micro-meteorological conditions in the field and ii) controlled environmental chamber experiments in the laboratory. Field measurements will be performed at Pallas (Arctic) and Sodankylä (sub-Arctic), Finland above the snow surface (open ground and forest canopy). Control experiments will be carried out in the Cold Climate Container (CCC) at the University of Oslo, Norway. The aim will be to understand the mass transfer between snow and atmosphere, by measurements of the stable isotopes of hydrogen and oxygen in solid (snow), liquid (snow-melt) and vapor phase. By performing these experiments and measurements, the primary target would be to constrain the isotopic signature of sublimation flux and develop a model to simulate isotopic interactions between the snow layer and atmosphere. The findings from this study will have a multidisciplinary impact on understanding the influence of snow sublimation on atmospheric and terrestrial water balance in the snow-dominated regions of the world