Impacts of Climate Change

Climate Impacts on the Lake Simcoe Watershed

By downscaling global climate models to the Lake Simcoe watershed, we gained a better understanding of how the local climate is expected to change in the coming century.

Data for this exercise was provided by the Climate Change Hazards Information Portal and the Climate Atlas of Canada. These online resources provided climate projections from 25-37 General Circulation Models, downscaled to the Shanty Bay weather station, which has the longest uninterrupted climate data series in the watershed. Two emission scenarios, as identified by the International Panel on Climate Change were used in these models: a high carbon scenario (i.e. RCP 8.5); and a mid-carbon scenario (i.e. RCP 4.5). While the projections were developed based on best-available science, there are always uncertainties. We will ensure an adaptive management approach to monitor and assess the effectiveness of the recommendations and modify as necessary.

Water Quality in our Rivers and Streams

In the Lake Simcoe watershed, the greatest impacts to water quality will be in changes to phosphorus, chloride, and total suspended solids.

Water Quantity

Increased frequency and intensity of rain events, or more frequent snow melt events, can affect all aspects of the water cycle and water movement through the watershed.

Stream and River Ecosystems

Warming water temperatures, reduced snowpack, more frequent drought, and more extreme precipitation patterns will alter habitats for local aquatic species. Since individual species have specific habitat requirements, some species may be able to cope with or even thrive under new conditions, while others may struggle.

The Lake Ecosystem

Lake Simcoe provides watershed residents with many valuable socioeconomic and ecosystem services, including drinking water and wastewater assimilation, tourism, recreation, and irrigation. Unfortunately, climate change is impacting significant aspects of the lake ecosystem, and these important services will be impacted as a result.

Terrestrial Natural Heritage

When natural communities are healthy, resilient, and connected, they form a robust natural heritage system that provides the functions and services upon which we depend. These systems are vital for creating habitat, enabling the movement of species for survival, and maintaining natural diversity. These ecological functions provide valuable ecosystem services.