Geopolitical tensions are heating up on Canada’s borders, but the biggest threat may be from wildly fluctuating temperatures transforming the tundra and oceanIn early February, during the depths of winter, Twin Otter aircraft belonging to the Canadian military flew over the vast expanse of the western Arctic looking for sea ice. Below, sheets of white extended beyond the horizon.But the pilots, who were searching for a suitable site to land a 34-tonne (76,000lb) Hercules transport plane a month later, needed ice that was 1.5-metres (5ft) thick. Continue reading...