Remote Sensing of Surface Water Connectivity across the Canadian Shield

Abstract:

As projected climate change intensifies the hydrologic cycle in the Arctic and subarctic, understanding the fundamental hydrologic processes of these environments will be critical for managing and predicting water resources. Surface water connectivity, in particular, is a critical control on river discharge in poorly drained, lake-dominated environments. This is especially true for the Canadian Shield, a vast, remote, bedrock-dominated region of northern Canada. In the Canadian Shield, discharge relies on intermittent topographically controlled connections, called “fill-and-spill” events, between water bodies. These connections only occur when topographic depressions fill to their storage capacities and spill downstream. Understanding topographic connectivity is therefore integral to a comprehensive understanding of downstream discharge patterns in the Canadian Shield.

In this research, topographic connectivity in the Canadian Shield is mapped using high-resolution digital elevation models and remote sensing imagery. By analyzing a digital elevation model, we show where intermittent connections between usually separate water bodies might be found. We then use high-resolution satellite imagery to map these connections and any associated surface water changes overtime. Finally, the potential future use of remote sensing data products for understanding the hydrologic connectivity of the Canadian Shield in a wetter climate will be discussed.