Caravan double-parked along the Alcan Highway at midnightPhotograph: Roger NorumSnowy ridges of Denali National ParkPhotograph: Roger NorumThe Yukon River wends its way across Western Canada into Alaska, finally emptying out in the Bering StraitPhotograph: Roger NorumThe Brooks Range seen from an eight-passenger Cessna aircraftPhotograph: Roger NorumCrosscheck: Approaching landing just outside of Deadhorse, AKPhotograph: Roger NorumHave petrol, will travel: Northern Alaska's desolate permafrost road Photograph: Roger NorumStanding at the southern edge of the Arctic Ocean with dadPhotograph: Roger NorumSome of the crudest oil in the world flows through the Alaska Pipeline. Currently, 700,000 barrels are pumped each day at a rate of 5.4 miles per hour, taking just over five days to complete the journey from Prudhoe Bay to Valdez. Because of the permafrost, 420 miles of the pipeline must run above groundPhotograph: Roger NorumAlaska contains 13% of the world's glaciers. Over the past century, the state's glaciers have lost approximately 500 cubic miles of ice to meltwater.Photograph: Roger NorumBoreal forest occupies 44% of the Alaskan interiorPhotograph: Roger NorumCrossing the Arctic Circle with dadPhotograph: Roger NorumSummer solstice, 1am at the Canada–US borderPhotograph: Roger NorumSunday Cross: Canada–US border post Photograph: Roger NorumAlaskan Bill Miller and son Trey use a DIY suction machine powered by a lawnmower engine to pan for gold in a creek near Boundary, AK. Here, Trey finds a 1/2 ounce piece of gold. Their gross (and net) profit each summer averages about $30,000.Photograph: Roger NorumMoose crossing, southern AlaskaPhotograph: Roger NorumAlaska vanity plate in Canada's Yukon Photograph: Roger NorumNative American Iñupiaq ritual masks Photograph: Roger Norum