Permafrost change and its engineering effects under climate change and airport construction scenarios in northeast China

Climate warming leads to the aggravation of infrastructures and environmental risks in permafrost regions. There are few reports about the interaction between airport runway and permafrost foundation. Based on long term field monitoring, remote sensing and comparative analysis approaches, our study quantitatively investigates the impacts of runway and climate on permafrost in northernmost China, and also the engineering problems are analyzed. Results show that the atmospheric inversion in winter controls the regional permafrost distribution in the study area. Ground surface warmed significantly after vegetation removal because of the runway construction. The maximum temperature difference among the forest, the swamp and the bared gravel can reach to 30 °C in summer. Such surface alterations caused abnormally rapid degradation of permafrost within the context of climate warming. The rate of permafrost table deepening varies from 0.461 to 0.590 m/a over the 2007–2017 periods. Also, the annual mean ground temperature at the 13 m depth increased at a rate of 0.054–0.130 °C /a. Its annual increase value is 0 ∼ 0.47 °C, with an average 0.108 ± 0.124 °C. In turn, permafrost degradation caused runway safety problems, such as the decrease of bearing capacity, increase of longitudinal slope, decrease of planeness, pavement cracks, density decrease of the foundation and cement concrete pavement cavity. However, in the natural places, the permafrost remained relatively stable and didn’t show a continued degradation trend. The permafrost table fluctuated with air temperature changes. Its interannual fluctuation range is 0 ∼ 0.25 m, with an average 0.08 ± 0.08 m. The interannual fluctuation range of ground temperature at the depth of 13 m is 0.01 ∼ 0.10 °C, with an average 0.06 ± 0.03 °C. In addition, the zero curtain phenomena were observed at the study site. Once the zero curtain periods were over, the ground temperature warmed rapidly. These findings have positive implication for new runway design in permafrost regions.