Climate change made June’s heatwave in eastern Canada “two to ten times more likely,” Canada's Environment Ministry notes in an unprecedented study.
In mid-June, Canada's Atlantic coast provinces, Quebec and Ontario, experienced temperatures seven to ten degrees above the seasonal norm.
The Ministry's study analyses the role of human activity in recent heatwaves by comparing current and pre-industrial-period data.
Temperature records from the 1870s, when measurements first began, were broken. For instance, the Saint John area in New Brunswick hit 34.5 degrees Celsius.
Abnormally high day temperatures were revealed, along with high humidity and unusually warm nighttime temperatures, providing “little or no respite.”
The heatwave was made significantly more probable due to climate change, the Ministry concluded, stressing that it was rare to see such weather conditions so early in June.
The first of its kind in Canada, the new "rapid attribution system for extreme weather events" aims to quickly determine the relationship between the heat wave and human-induced climate change so as to provide a concrete illustration of climate disruption.
Currently in a testing phase, it will next be extended to other extreme events such as cold waves or floods, the Ministry said.
It will analyse, in particular, the current heatwave affecting western Canada, where over 50 daily temperature records were broken in British Columbia and Alberta in recent days.
