Rating B (Moderate Progress)
The amount of water in Canadian lakes, rivers, wetlands, and aquifers has been impacted by climate change, evidenced by more flooding, toxic algae blooms, risk of waterborne diseases, drought, fires, hail storms, tornadoes, higher temperatures causing glacier melting, poor quality drinking water, and weather variability in temperature, rainfall, and snowfall. Rivers and lakes are being stressed as cities grow and remove natural vegetation that replenishes groundwater and moisture in the soil, prompting erosion and floods.
Agriculture Canada states that increased temperatures, longer growing seasons, shifting precipitation patterns, and increased frequency and intensity of extreme climate events bring challenges and opportunities to agricultural production. This results from water stress (flooding, drought), heat stress, wind damage, increased pest and disease pressures, water availability, delayed plantings or crop failures, and reduced soil health. As industry and manufacturing use much water for processes, they can experience supply chain disruptions, productivity losses, structural damage, and cleanup costs after extreme weather events.
Global Water Futures tells us that the rate at which water moves through the water cycle is accelerating, changing weather and precipitation patterns within disrupted hydrologic cycles by altering water flow and water chemistry. Climate change is changing aquatic ecosystems, given increases in air and water temperature, decreases in ice and snow cover, and changes in the timing and amount of precipitation. This amplifies the negative effects of development and pollution on watersheds and damage to aquatic life.
Canada’s Changing Climate Report identifies several climate-burdened water issues over recent years that continue to grow worse:
- Oceans surrounding Canada have warmed, become more acidic, and less oxygenated, consistent with observed global ocean changes over the past century.
- Effects of widespread warming include more extreme heat, less extreme cold, longer growing seasons, shorter snow and ice cover seasons, earlier spring peak streamflow (runoff), thinning of glaciers (western Canada), thawing permafrost, and the threat of rising sea levels. Glacier loss reduces streamflow and increases the possibility of drought. Permafrost conditions link to hydrological (drainage) and land surface processes (erosion and slope movements), ground warming, and thawing.
- Precipitation is increasing for most of Canada, although summer rainfall decreases in some areas of southern Canada, with a shift toward less snowfall and more rainfall. This results in rain-generated local flooding. Extreme summer dry periods are beginning to increase drought, mainly through the southern Prairies and interior BC.
- Canada has more than 8500 rivers and streams. Seasonal availability of freshwater is changing, with an increased risk of summer water supply shortages due to warmer winters, earlier snowmelts, and glacier loss. Warmer summers increase evaporation of surface water, contributing to reduced Prairie water availability.
- A warmer climate has meant more extreme hot temperatures, heatwaves, and increased drought and wildfire risks, for example, in southern Alberta and interior BC. More intense rainfalls increase urban flood risks, as evident in the southeast prairies, Alberta, Red River (Manitoba), Saint John River (New Brunswick), and BC.
- Canadian areas of the Arctic and Atlantic Oceans have experienced longer and more widespread sea-ice-free conditions, increasing the risk of damage to coastal infrastructure and ecosystems. Several of the Great Lakes have dropped water levels, given climate change. Seasonal sea ice along the east coast has ice melting each spring completely, and melting sea ice in the Gulf of St. Lawrence, James Bay, and the eastern part of Hudson Bay impacts marine ecosystems.
- Coastal flooding is increasing in many areas of Canada. Changes in local sea levels combine rising seas and local land subsidence.
Canada has legislative policies to protect water – visit https://www.canada.ca/en/ environment-climate-change/services/water-overview/governance-legislation/federal-policy.html.
A new Canada Water Agency’s (May 2023) priority is modernizing the Canada Water Act to reflect changes in fresh water in Canada, climate change, and Indigenous rights. Canada’s budget for 2023 will renew and expand the Freshwater Action Plan through this new agency to protect Canada’s reserves, i.e., Lake Winnipeg, the St. Lawrence River, the Great Lakes, and the Mackenzie River.
Canada’s progress in preventing and adopting climate-related water issues appears to be a B – Moderate Progress. Work is needed to forecast floods and droughts and strengthen quality drinking water access for all First Nation communities.
This Post was submitted by Climate Scorecard Canada Country Manager Diane Szoller.