A frozen mass of soil, rock, trees, ice, and other debris is very close to the Dalton Highway in Alaska (Figure 1). State officials now plan to move a 4000 ft (1220 m) section of the highway. The frozen debris lobe has been moving downhill for hundreds of years and is expected to reach the highway in the next 4-6 years. It is less than 100 ft (30 m) from the highway and is moving about 15 ft (4.6 m) annually. The Dalton Highway – referred to locally as the “Haul Road” – is critical to the economy of Alaska, as trucks use this route to bring supplies to North Slope oil production facilities.

More information is available from the Alaska Dispatch News and the Frozen Debris Lobes website at the University of Alaska-Fairbanks.