Risk assessment of potential thaw settlement hazard in the permafrost regions of Qinghai-Tibet Plateau

Jie Ni; Tonghua Wu; Xiaofan Zhu; Xiaodong Wu; Qiangqiang Pang; Defu Zou; Jie Chen; Ren Li; Guojie Hu; Yizhen Du; Junming Hao; Xiangfei Li; Yongping Qiao

doi:10.1016/j.scitotenv.2021.145855

Risk assessment of potential thaw settlement hazard in the permafrost regions of Qinghai-Tibet Plateau

Sci Total Environ. 2021 Jul 1:776:145855. doi: 10.1016/j.scitotenv.2021.145855. Epub 2021 Feb 20.

Authors

Jie Ni¹, Tonghua Wu², Xiaofan Zhu³, Xiaodong Wu³, Qiangqiang Pang³, Defu Zou³, Jie Chen³, Ren Li³, Guojie Hu³, Yizhen Du¹, Junming Hao¹, Xiangfei Li¹, Yongping Qiao³

Affiliations

¹ Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China. Electronic address: thuawu@lzb.ac.cn.
³ Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.

PMID: 33652323
DOI: 10.1016/j.scitotenv.2021.145855

Abstract

Climate warming could exacerbate the occurrence of thaw settlement hazard in the permafrost regions of the Qinghai-Tibet Plateau (QTP), which would threaten the stability of engineering infrastructure in cold regions. The risk associated with permafrost settlement, valuable for the regional sustainable development, remains poorly assessed or understood on the QTP. In this study, three common Geo-hazard indices were used to assess the settlement risks in the permafrost regions of the QTP, including the settlement index, the risk zonation index, and the allowable bearing capacity index. However, large spatial differences existed in simulating the risk maps by using the abovementioned Geo-hazard indices. Hence, we developed a combined index (I_c) by integrating the three indices to reduce the uncertainty of the simulations. The results indicated that the ground ice is a critical factor for assessing the settlement risk in permafrost regions. We also applied the I_c to assess the settlement risk along the Qinghai-Tibet Railway (QTR). The proportion of low-risk area along the QTR would be the highest (45.38%) for the future periods 2061-2080 under Representative Concentration Pathway 4.5. The medium-risk area combined with the high-risk area would be accounted for more than 40%, which were located at the boundary of the present permafrost regions. Therefore, the corresponding adaptation measures should be taken to reduce the potential economic losses caused by the high-risk regions to the infrastructure. Overall, the results would present valuable references for engineering design, construction and maintenance, and provide insights for early warning and prevention of permafrost thaw settlement hazard on the QTP.

Keywords: Engineering construction; Permafrost; Qinghai-Tibet Plateau; Thaw settlement hazard.