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The seasonal snowcover and snowmelt (2008-2010) of an extensive low-gradient wetland at Polar Bear Pass, Bathurst Island, Nunavut, Canada (7540' N, 9830' w) was examined. This wildlife sanctuary is characterized by two large lakes and numerous tundra ponds, and is bordered by rolling hills with incised hillslope stream valleys. In arctic environments snow remains one of the most important sources of water for wetlands. End-of-winter snowcover measurements (snow depth, density, water equivalent) together with direct and modeled estimates of snowmelt provided an assessment of the seasonal snowcover regime of representative terrain types comprising upland (plateau, stream valley, late-lying snowbed) and lowland landscapes (wet meadow, ponds, lakes). In all three seasons, deep and persistent snowpacks occurred in sheltered areas (stream valleys) and in the lee of slopes adjacent to the wetland. Exposed areas yielded shallow snowpacks (e.g. plateau, pond) and they melted out rapidly in response to favorable weather conditions. Overall, the basin snowcover and melt progression was dominated by accumulation and melt occurring in upland areas. We surmise the sustainability of this low-gradient wetland is dependent on snowmelt contributions from upland sites. [ABSTRACT FROM AUTHOR]

Snowmelt onset and end date estimates are made from QuikSCAT scatterometer measurements in the Canadian High Arctic wetland of Polar Bear Pass (PBP) and the surrounding region of Bathurst Island, Nunavut. In situ data within PBP is used to validate QuikSCAT snowmelt onset/end date estimates. Results indicate that within PBP from 2000 to 2009, the mean snowmelt onset date was Year Day (YD) 162, the mean snowmelt end date was YD179, and the mean snowmelt duration was 17 days. More interannual variability was apparent in snowmelt end date and duration compared with onset, and only snowmelt end date was significantly correlated with mean June air temperature at −0.78. Cooler air temperatures in 2004 contributed to a long snowmelt duration of 24 days, and the very short snowmelt duration in 2007 of just 11 days was caused by rapid and sustained increases in air temperature. For snowmelt end date and duration the mean spatial pattern revealed two centres of later snowmelt end date/longer snowmelt duration over Bathurst Island. They were separated by early snowmelt end date/short snowmelt duration in PBP. These patterns are in agreement with the spatial distribution of mean May to July air temperature over Bathurst Island and are likely influenced by the local-scale topography of Bathurst Island. Given the correlation between air temperature and snowmelt end date, we might expect quicker snowmelt under increased warming. The latter process may have implications for the sustainability of the PBP wetland under a warmer climate. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study examined the end-of-winter snow storage, its distribution and the spatial and temporal melt patterns of a large, low gradient wetland at Polar Bear Pass, Bathurst Island, Nunavut, Canada. The project utilized a combination of field observations and a physically-based snowmelt model. Topography and wind were the major controls on snow distribution in the region, and snow was routinely scoured from the hilltop regions and deposited into hillslopes and valleys. Timing and duration of snowmelt at Polar Bear Pass were similar in 2008 and 2009. The snowmelt was initiated by an increase in air temperature and net radiation receipt. Inter-annual variability in spatial snowmelt patterns was evident at Polar Bear Pass and was attributed to a non-uniform snow cover distribution and local microclimate conditions. In situ field studies and modelling remain important in High Arctic regions for assessing wetland water budgets and runoff, in addition to model parameterization and validation of satellite imagery. Editor Z.W. Kundzewicz Citation Assini, J. and Young, K.L., 2012. Snow cover and snowmelt of an extensive High Arctic wetland: spatial and temporal seasonal patterns. Hydrological Sciences Journal, 57 (4), 738–755. [ABSTRACT FROM PUBLISHER]

The article presents a study on the hydrology of the Canadian High Arctic hillslope-wetland catchments at the Polar Bear Pass including the Landing Strip Creek and the Windy Creek. It discusses the findings of the water balance framework, movement of the water, and response to rain of both streams. It cites the role of post-snowmelt season runoff to summer precipitation which is greatly affected by soil-type, vegetation, and ground ice.