Disappearing semi-permanent snow in the High Arctic and its consequences

Abstract

ABSTRACT. Semi-permanent snow is part of the continuum between seasonal snow and glacier ice. Although ubiquitous in the High Arctic, most late-lying snow banks and snow beds have lost their perennial status over the past decade as the summers have become progressively warmer. The loss over the past decade is the most unprecedented since aerial photography of the Canadian Arctic islands was first undertaken over half a century ago, and it has produced observable thermal, hydrological and ecological impacts. Where the ground has become exposed beneath the perennial snow cover, seasonal ground thaw has deepened. Tundra ponds and patchy wetlands fed principally by meltwater in the summer have suffered water-level decline or desiccation. The water balance of headwater basins is also affected, losing a buffering vehicle that accumulates storage surplus from the wet cool years to support streamflow and evaporation in the dry warm years. The tundra vegetation, already sparse, undergoes changes in the long term. As an essential source of water in the polar desert environment, the widespread distribution of semi-permanent snow magnifies its Arctic-wide importance.

Snow cover variability at Polar Bear Pass, Nunavut

“…3). This finding does differ from Woo and Young (2014), who documented the rapid disappearance and loss of semipermanent snowbeds occurring on hillslopes and in incised valleys, and attributed it to warmer air temperatures since about 2000 (Woo and Young 2014).…”

“…Northern Eurasia is now experiencing above normal snow cover (Cohen et al 2012) and in the Canadian High Arctic, Gauthier et al (2016) report that at Qarlikturvik Valley, Bylot Island snow depths have been increasing since 1993 but snowmelt is earlier. In response to recent warming (since 2000), Woo and Young (2014) confirm the loss of semipermanent snowbeds in the Canadian High Arctic. Recent climate modeling efforts suggest that loss of arctic sea ice is contributing more heat into the overlying atmosphere during fall and early winter.…”

“…In response to recent warming (since 2000), we are already seeing the demise of semipermanent snowpacks (Woo and Young 2014). Deep hillslope and valley snowbeds may build up in cooler, snowier years but whether they can persist over one or two seasons like they did in the early 1970s is not yet well known, especially when they lose thick basal ice layers in warm seasons (Woo and Young 2014).…”

Spatio-temporal sensitivity of MODIS land surface temperature anomalies indicates high potential for large-scale land cover change detection in Arctic permafrost landscapes

“…It has a typical polar desert climate with long, cold winters and short, cool summers (Young & Labine, 2010 (Mekis & Vincent, 2011). Air temperatures have been warming at both Resolute Bay and Polar Bear Pass over the last decade (Woo & Young, 2014).…”

Controls on spatial and temporal patterns of soil nitrogen availability in a High Arctic wetland

“…This is consistent with research conducted by 10 Stewart et al (2014), where N mineralization rates, and consequently NH4 + levels, were higher in lower lying areas. The increase of nutrient concentrations from east to west also follows the east to west retreat of the snowpack as the melt season progressed, which ties back to the importance of this perennial snowpack to the wetland in this environment (Woo and Young, 2014).…”