How well do we understand the influence of drifting and blowing snow in extreme environments?

• Main Authors: Sharma, Varun, Dujardin, Jérôme, Walter, Benjamin, Gerber, Franziska, Lehning, Michael
• Format: Text
• Language: unknown
• Published: 2020
• Subjects: Antarc*; Antarctica
• Online Access: http://infoscience.epfl.ch/record/274135

Extreme cold environments such as the polar regions and high mountain areas are characterised by unknown precipitation quantities and a high variability of snow and ice masses. A key player in understanding the surface mass balance in these areas is drifting and blowing snow. Apart from the surface mass balance, drifting and blowing snow may perturb the surface structure of the boundary layer resulting in feedback loops that have not been sufficiently explored, especially at large scales. In this contribution we review recent advances in measuring and modelling drifting and blowing snow as well as their effects on the atmosphere and the surface mass balance. In particular, we suggest that current models may underestimate drifting snow sublimation because they assume saturation close to the surface and do not adequately represent the effects of transient (turbulent) wind fields. We highlight the importance of knowing not only the frequency of snow transport occurrence but also the height distribution of both mass flux and humidity for an accurate assessment. Therefore, we present first ground-based micro rain radar measurements of blowing snow clouds in Antarctica and show examples of blowing snow events which are not represented in current weather and climate models. Additionally, recent advances made is simulations of blowing snow clouds in Antarctica are present and compared with measurements. These simulations play the critical role of understanding the effect of drifting and blowing snow at continental scale. Results from such simulations, particularly on vapor contribution due to blowing snow sublimation will be presented as examples to highlight their utility.