Supervised by:

Daniel Fortier (Regular Member (Co-researcher))

Research project description

Ground ice of eastern Canadian High Arctic polar desert

Introduction

The cryosphere of the polar deserts is strongly affected by climate change, both in terms of permafrost, sea ice, glaciers and nival coverage. For permafrost, the key element of its stability is ground ice. Ground ice can be defined as ice within frozen or partly frozen ground, irrespective of the form of occurrence or the origin of ice. The amount of ground ice within permafrost varies markedly between frozen sediment based on latitude, elevation, and continentality. The permafrost ice of the polar deserts of the Canadian High Arctic has so far been little studied. Having a better knowledge of quantity and distribution of permafrost ice is essential to simulate the future response of polar deserts to climate change and to evaluate its impacts on hydrology, geomorphology, vegetation and biogeochemical cycles.

Objectives

The principal aims of this project are: To model the formation and development of polar desert ground ice using physical modeling in permafrost simulators and numerical cryo-hydro modeling. To assess the role of snowmelt water and subsurface flow in the formation of polar desert permafrost ice. To extrapolate permafrost ice data obtained in the laboratory and in the field at the landscape scale using artificial intelligence-assisted remote sensing.

Study Sites

Ward Hunt Island lies at the northern tip of North America, 6 km off the northern coast of Ellesmere Island in the High Arctic of Nunavut. The northern Ellesmere/Ward Hunt Island region is subject to an extreme polar desert climate, corresponding to the arid portion of the periglacial regions of Canada. The mean annual air temperature for this region ranges from -15 to -17.5°C. The average air temperature in winter months is in the range of -30 to -35°C, while the average in summer months is in the range of 1 to 5°C. Given its extreme northern latitude, Ward Hunt Island experiences large fluctuations in incident radiation, from continuous daylight in summer to continuous darkness in winter.

Material and methods

The research question will be investigated at different scales, including landscape scale, plot scale, and process scale. The methods used in this research project are: Physical modeling of permafrost ground ice dynamics in temperature-controlled simulators using climate scenarios recorded at Ward Hunt Island over the past ten years. Numerical thermal modeling of active layer and permafrost based on field measurements and physical modeling. Use of remote sensing (radar interferometry, multi-spectral, panchromatic imaging) to model the lateral and vertical distribution of permafrost ice and incorporate the results of the research into the 'land system model' CLASS.

References

-Murton, J., Ground ice and cryostratigraphy. 2013. -Muller, S.W., ... Permafrost, Or Permanently Frozen Ground: And Related Engineering Problems. 1945: Army map service, US Army. -Murton, J.B. and H.M. French, Cryostructures in permafrost, Tuktoyaktuk coastlands, western arctic Canada. Canadian Journal of Earth Sciences, 1994. 31(4): p. 737-747. -Woo, M.-k., Permafrost hydrology. 2012: Springer Science & Business Media. -Smith, M., Observations of soil freezing and frost heave at Inuvik, Northwest Territories, Canada. Canadian Journal of Earth Sciences, 1985. 22(2): p. 283-290. -Paquette, M., D. Fortier, and W.F. Vincent, Water tracks in the High Arctic: a hydrological network dominated by rapid subsurface flow through patterned ground. Arctic Science, 2017. 3(2): p. 334-353. -French, H.M. and P. Williams, The periglacial environment. Vol. 341. 1976: Wiley Online Library. -Mackay, J.R., The frost heave of stones in the active layer above permafrost with downward and up

Research Site Coordinates