The World in 2050_ Four Forces Shaping Civilization's Northern Future - Laurence C. Smith [87]
The big message here is that climate warming presents a severe challenge to current and future physical infrastructure in northern permafrost areas. The structural strength of many soils will be reduced, threatening existing structures and making new ones more expensive to engineer and maintain. Some permafrost landscapes will slump, collapse, or suffer hydrological changes, rendering them even less appealing for human activities than they are now.
Projected losses by 2050 in (1) the structural integrity of permafrost soils, a threat to buildings and other permanent infrastructure; and (2) suitably freezing temperatures for the construction of temporary winter roads over wet or soft areas.
The map379 on the previous page illustrates the scale of this problem by midcentury. Part of it derives from a new model of permafrost load-bearing capacity developed by Dmitry Streletskiy, Nikolay Shiklomanov, and Fritz Nelson at the University of Delaware. Dark tones indicate reduced bearing capacities (structural strength) of permafrost soils associated with a middle-of-the road carbon emissions scenario, i.e., the “moderate” (SRES A1B) scenario described in Chapter 5. Widespread losses in Alaska, northern Canada, and most of Siberia suggest that problems of reduced ground strength to support pilings, building foundations, and other heavy installations will be particularly severe there.
The hatched lines on the map are unrelated to permafrost. They illustrate another sort of change that will occur, in places where the ground surface freezes less long and hard during winter than it does now. The repercussions of this are quite different from the threat to infrastructure posed by warming permafrost, as we shall see next.
Ice Road Suckers
The second way in which rising temperatures will make remote northern landscapes less accessible is by reducing our ability to travel on them using winter roads.
Winter roads, also variously called ice roads, snow roads, temporary roads, and other names, are a remarkably well-kept secret. As their name suggests, they are temporary features, requiring a hard, deeply frozen surface to work. Winter roads are used extensively in Alaska, Canada, Russia, and Sweden and are also used in Norway, Finland, Estonia, and several northern U.S. states. In truly remote areas they are the only kind of road at all. Yet, despite their importance, these transient travel lanes rarely show up on maps. Before the popular television series Ice Road Truckers was produced, few people even knew they existed. But in many parts of the North—especially wet, boggy areas—they are the only way to economically resupply villages, run construction projects, harvest timber, find oil and gas, or do just about anything. Away from rivers and coastlines the only other option is to use airplanes and helicopters, which are extremely expensive.
In contrast to its biological life, economic activity on northern landscapes springs to action in winter, after the ground freezes and ground vehicles can be brought in. With remote distances and low population densities, the cost of permanent roads is rarely justified. In contrast, even the most expensive of winter roads—built up like an ice-skating rink by repeatedly glazing it with water—costs 99% less to build.380 So in many remote areas, the road network is not fixed but an ephemeral ghost, expanding briefly each winter, then melting away again in the spring.
One famous winter road, featured in the first season of Ice Road Truckers, is the Tibbitt-Contwoyto ice road built each year in Canada’s Northwest Territories. It begins near the city of Yellowknife and runs six hundred kilometers northeast into Nunavut, supplying a string of highly lucrative diamond mines. This road traverses bog and lakes and can exist only for about two traffic-jammed