Canadian Press: Canadian scientists are sounding another environmental alarm with word that a massive Arctic ice shelf has broken free and is now adrift in the Arctic Ocean. The 50-square-kilometre Markham Ice Shelf broke away in early August, researchers say, and two large sections representing 60 per cent of the Serson Ice Shelf have also become detached. That means some 214-square-kilometres of Arctic ice shelves have been lost this summer, or about a quarter of what was left. It’s the …