Climate Change and Water

Water and SunUnderstanding the vulnerability of Canada’s water resources to climate change is vitally important. Water is one of Canada’s greatest resources. We depend on the availability of a clean, abundant water supply for domestic use; food, energy and industrial production; transportation and recreation; and the maintenance of natural ecosystems. It is estimated that water’s measurable contribution to the Canadian economy reaches $7.5 to 23 billion per year.

Natural climate variability causes some areas of the world to receive more water than others – creating wet, tropical rainforests and hot, arid deserts. The same is true across Canada; water is not distributed evenly. Some regions experience droughts and shortages and others flooding. Historically we have learned to adapt to these differences in climate by building communities near water sources or by altering where water flows. We build dams across rivers to store water for hydro-power generation, irrigation, urban water supply and flood control. We drain wetlands and clear forests to create farms and cities, and we divert water from where it flows naturally to where it is needed.

As demands for water grow in future, so too will impacts on the hydrologic cycle through these kinds of interventions. Climate change will create additional changes to the hydrologic cycle in addition to human interference. Our global climate is no longer as predictable as it once was. Traditional patterns of precipitation can no longer be depended upon. Thinking now about the way in which climate change affects the hydrologic cycle, and how these changes affect human societies and ecosystems, will permit earlier and more effective adaptation.

Read more: Climate Change Facts

Read Local: Climate Change in My Watershed

Adapted from Pollution Probe's Mainstreaming Climate Change in Drinking Water Source Protection Planning in Ontario Primer.