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In polar regions, and specifically in continental Antarctica, the local surface mass and energy balances can be largely controlled by snow transport in form of drifting and blowing snow particles, and sublimation both from the snow or ice surface and from the airborne snow particles. Adverse conditions in such extreme environments make continuous and reliable measurements of snow drift and sublimation a challenge, especially during the period of polar night and in absence of maintenance. Additionally, existing state-of-the-art snow mass and moisture flux measurement systems have relatively large power requirements, often resulting in spurious values or data gaps due to insufficient power supply from the autonomous wind and solar based power systems. In this contribution, we present observations of drifting snow events and latent heat fluxes obtained from collocated installations of classical eddy covariance instrumentation, optical snow particle counters, and acoustic particle flux devices deployed in Queen Maud Land, East Antarctica. We investigate the coherence of the optical and low-power acoustic snow drift measurements and compare them to numerical simulations of mass fluxes at the sensor sites. Furthermore, to mitigate the problems of potential power failure, low-power, fast-response humidity sensors are tested in laboratory and field settings to obtain latent heat flux estimates at largely reduced power consumption in comparison to eddy covariance measurements using infra-red gas analysers. Promising or successful novel systems may be a viable alternative for recording continuous time series of sublimation, in particular in the polar night season, and at significantly lower cost.
Varun Sharma, Michael Lehning, Franziska Gerber