Assessing the Importance of Potholes in the Canadian Prairie Region under Future Climate Change Scenarios

Abstract

The Prairie Pothole Region (PPR) of Canada contains millions of small isolated wetlands and is unique to North America. The goods and services of these isolated wetlands are highly sensitive to variations in precipitation and temperature. We evaluated the flood proofing of isolated wetlands (pothole wetlands) under various climate change scenarios in the Upper Assiniboine River Basin (UARB) at Kamsack, a headwater catchment of the Lake of the Prairies in the Canadian portion of the PPR. A modified version of the Soil Water Assessment Tool (SWAT) model was utilized to simulate projected streamflow under the potential impacts of climate change, along with changes to the distribution of pothole wetlands. Significant increases in winter streamflow (~200%) and decreases (~11%) in summer flow, driven by changes in future climates, were simulated. Simulated changes in streamflow resulting from pothole removal were between 55% for winter and 15% for summer, suggesting that climate will be the primary driver in the future hydrologic regime of the study region. This research serves as an important guide to the various stakeholder organizations involved in quantifying the aggregate impacts of pothole wetlands in the hydrology of the Canadian Prairie Region.

Climate Change Impacts on Reservoir Inflow in the Prairie Pothole Region: A Watershed Model Analysis

“…The climate of UARB is continental sub-humid characterized by long cold winters and a short summer [3,9]. Mean annual precipitation is 510 mm and mean annual temperature is 1.5 • C during the periods 1988-2017.…”

“…Climate change is predicted to significantly impact the availability of water resources around the world [1]. Scientific consensus is that increasing temperature will alter both the quantity and timing of regional precipitation, evapotranspiration, and soil moisture, which will in-turn affect hydrologic flows into lakes and streams [2][3][4][5]. Climate change is also predicted to increase precipitation intensity, which could lead to higher rates of surface runoff causing an increased risk of floods.…”

“…Climate change is also predicted to increase precipitation intensity, which could lead to higher rates of surface runoff causing an increased risk of floods. Increasing temperature will enhance evapotranspiration rate, which may increase the demand for water availability during the peak growing season [3,6]. With more than one-sixth of the earth population relying on glaciers and seasonal snowpacks for their water supply, the consequences of climate change and interrelated hydrological changes for future water availability are likely to be severe [7].…”

“…Based on numerous studies, climate change over the Prairie Pothole Region (PPR) of North America, which spans across Alberta, Saskatchewan, and Manitoba in Canada and extends into North Dakota, South Dakota, Iowa, Minnesota, and Montana in the United States, will significantly impact runoff that is driven by seasonal snowmelt [3,[9][10][11][12][13]. The Canadian portion of the Prairie region, especially the central part, is projected to warm over the next 60 years [3,14], which may result in excessive moisture risk [15] and frequent drought conditions. The latest report from Environment and Climate Change Canada (ECCC) projected a 6.5 • C rise in temperature for the Canadian Prairies [16].…”

“…For example, Canadian Regional Climate Model (CRCM) ver. 5 was utilized [3] to assess impacts of climate and land use change on the hydrology of the Upper Assiniboine River basin. While the study outlined that climate will play far more significant role in changing hydrologic regime of the watershed in comparison to the land use changes, the study's primary recommendation focused on the use of multiple climate models to conduct similar studies to come into a comprehensive recommendation.…”