Tamara Rud, 70, fishes in the River Polui in the arctic city of Salekhard some 2000 km (1242 miles) northeast of Moscow November 25, 2007. REUTERS/Vasily Fedosenko (RUSSIA)It’s hard to imagine how big some of the cracks are on this link to satellite images of the Arctic ice during winter – dark lines hundreds of miles (km) long abruptly appear off the Canadian islands at the bottom right of the picture as the ice swirls through the winter.