Effects of meteorology and soil moisture on the spatio-temporal evolution of the depth hoar layer in the polar desert snowpack

• Published in: Journal of Glaciology
• Main Authors: Gautier Davesne, Florent Domine, Daniel Fortier
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2022
• Subjects: Arctic snowpack; depth hoar; polar desert; soil moisture; thermal conductivity; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Arctic; Hunt Island; Resolute Bay; Ward Hunt Island; Journal of Glaciology; Tundra
• Online Access: https://doi.org/10.1017/jog.2021.105; https://doaj.org/article/a738ca8fa0fb4a3396ccd7d7deb5358e

In polar deserts, depth hoar (hereinafter: DH) growth is not systematic unlike on tundra and this is critical for snowpack properties. Here, we address the spatio-temporal variability of the DH layer in the polar desert at two sites in the Canadian High Arctic: Ward Hunt Island (83° N) and Resolute Bay (75° N). Our data show that, over humid areas, DH represented a larger fraction of the snowpack and was characterized by lower density and coarser crystals than over dry gravelly areas. Increased soil moisture extends the zero-curtain period during freeze-up, leading to stronger temperature gradients in the snowpack and greater kinetic metamorphism. Our results also demonstrate that the large inter-annual variability in DH is primarily driven by wind conditions in the fall since this key variable controls the initial snow density and snow onset date. These strong controls exerted by soil moisture and meteorological conditions on DH growth in polar deserts highlight the possibility of major changes in polar snowpacks physical properties in response to the rapid climate and environmental changes currently affecting these regions.