Relation between climate variability and groundwater levels in the upper carbonate aquifer, southern Manitoba, Canada

Modeled trends of key climate variables in the Winnipeg area show that the annual mean temperature has increased by about 1 °C over the past 105 years. Potential impacts of climate change on groundwater levels are investigated by analyzing the relationship between historical climate records and water levels in monitoring wells completed in the upper carbonate aquifer. Both precipitation and annual mean temperature display a strong correlation with annual groundwater levels in this aquifer. The correlation with temperature becomes stronger in the periods of higher annual mean temperatures. In areas where the aquifer is found at shallow depth, temperature has a greater influence than precipitation on groundwater levels. Results suggest that a trend of increasing temperatures, predicted by global climate models for this region, may reduce net recharge and affect groundwater levels.