I am in a tundra buggy, a giant moonrover-like vehicle designed to negotiate the bumpy subarctic tundra, and to provide a safe and lukewarm enclosure for temperate souls like me to encounter the Ice Bear. Several of them argue nearby, grouchy of hunger as they wait for Hudson Bay to freeze so they can hunt seals again after a long summer of fasting. The place is Churchill, in Manitoba, Canada, "polar bear capital of the world." The GPS says I am a snowball's toss south of latitude 66, that bump in the permafrost called the Arctic Circle. It is late autumn and a perfect circumpolar day - cloudless, amazingly windless, and almost above freezing. The sun's rays slant across the tundra for that edge of the day magenta cast that photographers love.