Polar Vortex Breakdown Causes Harsh Winter In Eastern Canada

Photo Credit: Brendan Hunter via iStock

Eastern Canada has experienced an intense winter, due to a breakdown in the polar vortex, a large mass of arctic air that usually remains trapped near the North Pole. This is a sharp contrast to Vancouver and the rest of the Lower Mainland, which has experienced an extremely mild winter — except for the past month.

Rising global temperatures due to climate change weakened the forces keeping the vortex stable. This occurs as rising arctic temperatures lead to a weaker polar jet stream, which keeps the cold constrained to the north.

While the phenomenon primarily impacts eastern cities, Vancouver has also seen some milder effects, seen in our increasingly extreme temperatures. Since the years 1998 to 2002, July temperatures have increased from 17.5°C to 19.2°C, a difference of 1.7°C. However, February temperatures have dropped by 5.3°C from 5.1°C to -0.2°C, according to Environment Canada. 

This climate change-induced event also masks the effects of global warming by ushering in colder temperatures — which can cause problems of its own. This breakdown can cause unpredictable storms, and more sudden onsets of extreme winter events due to the warming of the arctic, according to the US National Oceanic and Atmospheric Administration.

Projections by Environment Canada expect the cold period to ease soon. As temperatures begin to rise, Canadians can expect a hot summer throughout the country. However, climate change will lead to more frequent extreme weather events, and Canadians must be prepared for greater variability in future winters, according to the BC government website. 

As these events will become increasingly common, Environment and Climate Change Canada advises that Canadians should prepare an emergency kit, and buy an emergency radio.