What is the polar vortex – and how is it linked to climate change? | US weather | The Guardian
Polar Imperative: A History of Arctic Sovereignty in North America by Shelagh D. Grant
Life on the edge: Iñupiat communities and polar bears on Alaska's wild North Slope | National Geographic
Polar Vortex Building in North America
America and Russia work together during challenging times | WWF Arctic
In pictures: Polar vortex strikes North America - BBC News
Polar Bears Migrate from America to Russia as Temperatures Rise
Weakening polar vortex may yield longer, harsher winters in North America | AccuWeather
Arctic Weather Plunges into North America
Polar Bear Facts: Animals of North America - WorldAtlas
Weakened 'polar vortex' blamed for N. American chill
The U.S. is about to get a potent polar vortex blast - Science
Map of where bears live in North America
Arctic Weather Plunges into North America
Analysis: Polar Vortex collapse causes heavy winter for North America and the Nordics - Kjeller Vindteknikk
US braced for -50C temperatures as polar vortex bites
See all 70 polar bears in North American Zoos (interactive) - oregonlive.com
Eight die as polar vortex brings life-threatening temperatures to US Midwest | US News | Sky News
Polar Bear Watching Trips: Tailor-Made Ideas and Group Tours | Wildlife Worldwide
Home - American Polar Society
Polar Lights Model Kit – Captain America | Lake City Hobbies
As Polar Vortex Stirs, Deep Freeze Threatens U.S. and Europe - Bloomberg
Care For Us - Polar Bear | Wild Welfare
Polar vortex coming in November: Arctic blast to central, eastern U.S.
Cruises to Crossing the Arctic Circle | Holland America Line Cruises
Polar vortex: cold that has killed dozens to give way to 'spring-like' weather | US weather | The Guardian
Polar vortex whips millions of Americans with strong winds, freezing temperatures and even snow - CNN
We're not the only ones... Arctic storm with POLAR VORTEX cripples America | Nature | News | Express.co.uk
