Ice Roads

Simulated temperature evolution during melting season by Cryogrid3 in and below an ice road cover of 20cm thickness (darkblue: upper ice boundary, light blue: lower ice boundary, green: soil temperature at 30cm depth). The dotted black line illustrates surface air temperature (SAT), the dashed horizontal red line illustrates a soil temperature threshold at -5°C.
Simulated temperature evolution during melting season by Cryogrid3 in and below an ice road cover of 20cm thickness (darkblue: upper ice boundary, light blue: lower ice boundary, green: soil temperature at 30cm depth). (Graphic: Alfred-Wegener-Institut)

Global warming and the thawing of permafrost not only lead to destabilization of the soil in the permafrost regions of the Arctic, but also to a tendency to increasingly delimit the temporal useability of so-called ice roads. Ice Roads are annual winter transport routes that play an important role in supplying remote Arctic locations. Based on the Tundra Travel Rules, the Ice Roads may only be used under certain ground temperature conditions. The safety and the annual lifetime of these traffic routes are directly affected by the global warming and the shorter frost periods. The time slot within which ice roads may be used has decreased from about 200 days a year to about 100 days a year over the last 40 years.

On the one hand, the predictability of logistics is of utmost importance for companies operating in these hard-to-reach regions. On the other hand, serious and irreparable environmental damage can be caused if transport routes are used beyond a certain thermal stability limit. Reliable and timely risk assessment is therefore crucial from an economic as well as ecological point of view.

The permafrost model CryoGrid, which has been further developed as part of PermaRisk, is intended to help predict the usability and ecological compatibility of the Ice Roads. The CryoGrid model is already technologically able to predict the stability of such transport routes with the help of meteorological data from weather models. As part of this project, our scientific model will be used to develop demonstrator software for transport routes in Alaska.