Modeling permafrost properties in the Qinghai-Xizang(Tibet) Plateau  

作　　者：HU GuoJie ZHAO Lin WU XiaoDong LI Ren WU TongHua XIE ChangWei PANG QiangQiang XIAO Yao LI WangPing QIAO YongPing SHI JianZong 

机构地区：[1]Cryosphere Research Station on Qinghai-Xizang Plateau, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences

出　　处：《Science China Earth Sciences》2015年第12期2309-2326,共18页中国科学（地球科学英文版）

基　　金：financially supported by the National Major Scientific Project of China(Grant No.2013CBA01803);the National Natural Science Foundation of China(Grant Nos.41271081;41271086);the Foundation of One Hundred Person Project of the Chinese Academy of Sciences(Grant No.51Y551831)

摘　　要：Water and heat dynamics in the active layer at a monitoring site in the Tanggula Mountains, located in the permafrost region of the Qinghai-Xizang （Tibet） Plateau （QXP）, were studied using the physical-process-based COUPMODEL model, including the interaction between soil temperature and moisture under freeze-thaw cycles. Meteorological, ground temperature and moisture data from different depths within the active layer were used to calibrate and validate the model. The results indicate that the calibrated model satisfactorily simulates the soil temperatures from the top to the bottom of the soil layers as well as the moisture content of the active layer in permafrost regions. The simulated soil heat flux at depths of 0 to 20 cm was consistent with the monitoring data, and the simulations of the radiation balance components were reasonable. Energy consumed for phase change was estimated from the simulated ice content during the freeze/thaw processes from 2007 to 2008. Using this model, the active layer thickness and the energy consumed for phase change were predicted for future climate warming scenarioS. The model predicts an increase of the active layer thickness from the current 330 cm to approximately 350-390 cm as a result of a 1-2℃ warming. However, the effect active layer thickness of more precipitation is limited when the precipitation is increased by 20%-50%. The COUPMODEL provides a useful tool for predicting and understanding the fate of permafrost in the QXP under a warming climate.Water and heat dynamics in the active layer at a monitoring site in the Tanggula Mountains, located in the permafrost region of the Qinghai-Xizang(Tibet) Plateau(QXP), were studied using the physical-process-based COUPMODEL model, including the interaction between soil temperature and moisture under freeze-thaw cycles. Meteorological, ground temperature and moisture data from different depths within the active layer were used to calibrate and validate the model. The results indicate that the calibrated model satisfactorily simulates the soil temperatures from the top to the bottom of the soil layers as well as the moisture content of the active layer in permafrost regions. The simulated soil heat flux at depths of 0 to 20 cm was consistent with the monitoring data, and the simulations of the radiation balance components were reasonable. Energy consumed for phase change was estimated from the simulated ice content during the freeze/thaw processes from 2007 to 2008. Using this model, the active layer thickness and the energy consumed for phase change were predicted for future climate warming scenarios. The model predicts an increase of the active layer thickness from the current 330 cm to approximately 350–390 cm as a result of a 1–2°C warming. However, the effect active layer thickness of more precipitation is limited when the precipitation is increased by 20%–50%. The COUPMODEL provides a useful tool for predicting and understanding the fate of permafrost in the QXP under a warming climate.

关 键 词：PERMAFROST COUPMODEL hydrothermal processes phase change soil temperature soil moisture 

分 类 号：P642.14[天文地球—工程地质学]