Sydney Morning Herald: THE vast Arctic sea ice which spreads across the North Pole could disappear during the summer within a decade or two – or even by 2013 – leading scientists are warning. The Canadian Coast Guard’s strongest icebreaker, the Louis S. St Laurent, took the Herald and an ABC Four Corners crew with a team of scientists going to the Arctic at the beginning of this summer’s melt in July to explore the extraordinary changes there first hand. Only a few years ago, climate modellers …