Regional-Scale Evaluation of Landslide Distribution and Its Relation to Climate in Southern Alberta, Canada

Abstract

This work illustrates a semi-quantitative approach to evaluate changes in regional landslide distribution as a consequence of forecasted climate change, which can be adopted at other regions. We evaluated the relationship between climate conditions and landslide distribution at a regional scale. In this study, landslides on parts of the Battle, Red Deer, and Bow Rivers that are located within the Bearpaw Formation in Southern Alberta, Canada, were mapped, and their characteristics were compared. In order to find a relationship between the climate conditions and the mapped landslides, 30-year annual precipitation and other factors, such as slope aspect and geology, were compared between the river valleys. The results show that climatic conditions and the size and shape of the landslides are different in the Battle River area compared to the Red Deer and Bow Rivers regions. The weak Bearpaw overconsolidated shale and the bentonite layers throughout the region are sensitive to moisture and create favorable conditions for landslides in the river valleys. Further investigations into the long-term impact of climate on the formation of river valleys and the Bearpaw Formation support the argument that climate is one of the main factors in causing variations in landslide distribution across the study areas. These findings provide insight into possible changes in regional landslide distribution as a consequence of climate change.