Extreme weather event attribution

Extreme weather event attribution is the science of calculating how much human-caused climate change influences extreme weather events. The Rapid Extreme Weather Event Attribution system shows how human-caused climate change changes the likelihood of extreme weather events happening. It examines the extreme heat, cold, and precipitation events in regions covering all of Canada. The system uses climate models to compare three different climates: -the climate of the 1800s, based on levels of atmospheric gases that existed before the Industrial Revolution -the climate of today, based on observed levels of greenhouse gases and other results of human activity -a projected future climate reflecting additional global warming. Several days after a heat wave, extreme cold, or extreme precipitation event, scientists can compare the number of those extreme events in the three different climates. Then, they calculate the ratios of the three climates to find how much human activity has changed the chances of such an event happening. We use seven set statements to describe the likelihood that an extreme weather event was influenced by climate change from human activities. On one end of the…

Publisher

Environment and Climate Change Canada

Resources

2

Catalogue metadata updated

2026-08-21