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Interest is growing about how groundwater supplies will shift in warming northern terrains. We evaluated the seasonal and spatial pattern of groundwater flow in a wet meadow bordered by a late-lying snowbed and tundra ponds at Polar Bear Pass, Bathurst Island (75.7°N, 98.7°W). A water budget approach signalled the relative importance of groundwater inflow to tundra ponds. Groundwater flow across the wet meadow was estimated using a modified Darcy's equation, which requires information on both water and frost tables, and hydraulic conductivity. These data were obtained from 2007 to 2009 along a series of water wells extending from a late-lying snowbed across the wet meadow to a nearby study pond. Groundwater fluxes across the wet meadow were limited in magnitude and duration in a warm/dry year (2007), when the late-lying snowbed was the main external water source, a response differing from rainy/cool years (2008 and 2009). Overall, seasonal water budgets indicate that groundwater fluxes were minimal in the wet meadow and an adjacent tundra pond. Late-lying snowbeds play a limited role in sustaining wet meadows and ponds here. Summer precipitation and evaporation continue to drive wet meadow and tundra pond hydrological response in low-gradient wetlands, especially in the post-snowmelt season. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT A large number of wetlands, lakes and ponds exist in northern Canada, Alaska and Siberia, and the hydrologic and ecological processes in these water bodies are now responding to a changing climate. A large wetland, Polar Bear Pass (PBP), situated in the middle of Bathurst Island is considered to be one of the most important ecological sites in the region. Numerous ponds exist at PBP and are connected to their surrounding watersheds by streams and groundwater inflow, receiving varying amounts of water and nutrients. In 2008 and 2009, the representative hydrology of typical ponds at PBP along with their quantity of dissolved organic and inorganic carbon (DOC and DIC, respectively) was evaluated. Pond DOC and DIC loads and composition differ depending on the presence or absence of one or more hydrologic linkages that a pond has with its catchment. Elevated DOC loads were mostly of terrestrial origin and occurred in ponds receiving meltwater from snowbeds and discharge from hillslope creeks. The seasonal shift in connectivity of a pond to its catchment was critical in controlling DOC loads and concentrations. The frequency and duration of summer precipitation had a strong control on pond hydrologic connectivity and elevated the contribution of terrestrial DOC from wetland to ponds, especially ones that were hydrologically connected. The estimated DOC yields from wet meadow catchments highlight their importance as a source of carbon to pond ecosystems downstream. These wetland areas and ponds are potentially significant pools of carbon and are sensitive to future climate changes in permafrost-dominated environments. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

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]

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.