Prediction of Climate Change Impact on a Highway in Warm Permafrost

Climate warming is causing a widespread impact on the built infrastructure, such as roads, airports, and pipelines, and threaten their safe operation in the broad cold regions. Such problems are particularly severe in areas where ice-rich and thaw-unstable warm permafrost exists extensively. This paper presents the preliminary results of a case study on a highway in Bethel, Alaska, located in deep, warm permafrost in western Alaska. The climate change influence on the thermal state of warm permafrost and its potential impact on the built infrastructure are assessed. We first analyzes the characteristics of the near-surface air temperature predictions from 31 climate models in the fifth phase of the Coupled Model Intercomparison Project (CMIP5) for the next century. The air freezing and thawing indices are evaluated from the climate modeling results and compared with historical data. A thermal model of a selected ice-rich soil profile is built and used to assess the ground temperature variation and permafrost degradation during the next century. Subsequently, permafrost thaw settlement is predicted, and their potential impact on the built transportation infrastructure is discussed.