98 IEEE GEOSCIENCE AND REMOTE SENSING MAGAZINE SEPTEMBER 2022 Global Warning Satellite (Human and Natural Factors) Temperature Change Land Temperature Increase of Permafrost Regions Precipitation Land Cover Change Permafrost Degradation ALT Variation Permafrost Engineering Stability Permafrost Deformation Vegetation Earth-Air Exchange Active Layer Permafrost Hydrological and Plant Ecological Characteristics Soil Moisture Changes Freeze-Thaw Cycles of Active Layer FIGURE 3. The interaction among permafrost environmental factors, engineering facilities, and the soil freezing and thawing process in the permafrost region. (Source: Reproduced from Jiang et al. [63] with modifications.) Lake Radar Signal