Accelerating Arctic warming has shortened the duration and extent of areas of ice road use across the Far North, scientists and industrial users have been saying for years.
Now a new study Scientists from Nanjing University in China have quantified these losses for different regions of the Arctic, including Alaska, where ice roads are important seasonal transportation routes to many remote areas.
The study is based on satellite data and assesses climate, landscape and sea ice conditions as they change from 1979 to 2017. The study does not track the construction or use actual ice roads; rather, it follows the conditions that make it possible to build and use stable ice roads.
The analysis shows that across the Arctic and throughout the long winter, significant areas went from suitable for ice road building to unsuitable. In Alaska, the biggest changes occurred in December and April, according to the study. But even during the months of January, February and March, the time when winter conditions are at their peak, there have been losses of suitable ice road conditions in Alaska, the study found.
“We have demonstrated that potential ice roads have decreased significantly over the past few decades,” the study said. With the loss of potential ice road area, the later onset and earlier end of cold conditions “all provide evidence that the potential time window for ice road construction in the Panarctic is shrinking.
The study is published in the journal Environmental Research Letters.
For Alaska, he assessed conditions in western and interior Alaska as well as the North Slope.
Ice roads of various types have long been used as seasonal transportation routes in many rural areas of Alaska. The frozen Yukon River, for example, has been considered a naturally created ice road, and the frozen surface of the Kuskokwim River is groomed every winter to serve as a temporary ice road.
Commercially, ice roads are of particular importance on the North Slope, where oil companies use them to avoid damage to the tundra and permafrost below. Companies typically construct ice roads to access exploration and development sites; exploration drilling is done in winter, when the tundra is frozen and covered with snow. In the summer, the ice roads melt and the tundra becomes soft, soggy and difficult to navigate.
Oil companies and other entities also use the frozen tundra – with no ice roads at the top – for winter travel. For trip to the tundra to be permitted, ground temperatures and snow cover must meet thresholds set by state regulators.
Records from the Alaska Department of Natural Resources show that the tundra travel season on the North Slope has declined significantly since the 1970s, when travel seasons of around 200 days per year were typical, until today, when tundra travel is permitted for about 130 days a year. . For several recent years, conditions in the Brooks Range foothills region of the North Slope have never reached the thresholds required to allow tundra to shift in these areas.
The North Slope ice road season deviates slightly from this pattern. MNR began reporting the ice road season separately from the tundra travel season beginning in winter 2003-2004. During the first decade of these separate measurements, the length of the ice road season fluctuated widely, from a high of 209 in the winter of 2010-11 to a low of 123 in the winter of 2007-08. . Over the next decade, the seasons become somewhat more consistent, hovering between 161 and 200 days per year, according to DNR reports.
The Department’s Mines, Lands and Water Division has refined its regulatory system for tundra travel and ice roads to help preserve the length of the seasons. There was also constructive adaptations to achieve this objective, such as the pre-compaction of snow and the storage of ice chips on the ground. Nevertheless, Arctic Alaska’s changing climate is expected to continue to pose challenges challenges ice road construction on the North Slope and travel across the tundra.
Alaska Beacon is part of States Newsroom, a network of news outlets supported by grants and a coalition of donors as a 501c(3) public charity. Alaska Beacon maintains editorial independence. Contact editor Andrew Kitchenman with any questions: info@alaskabeacon.com. Follow Alaska Beacon on Facebook and Twitter.
