Alaska: Earth's Frozen Kingdom

The land is bathed in 24-hour sunlight during the short Alaskan summer, luring hummingbirds up from Mexico, exposing deserts in the Arctic and relying on parachuting firefighters to tackle forest fires in its vast wilderness. Grizzly bears fatten up on a sudden wealth of salmon, a caribou calf joins a vast herd on its great migration and a huge male moose finds unlikely ways to impress a female. Among the human population, a dedicated grower of giant vegetables takes his half-ton pumpkin to the Alaska State Fair