Asymmetric East‐West Changes in Mountain Fog Driven by Urbanization and Climate Warming

Abstract Fog is a vital component of montane climates, providing essential moisture for cloud forests and supporting the productivity of high‐value crops. This life‐sustaining feature, however, is increasingly vulnerable to disruption from rapid urbanization and climate change. To investigate the individual and combined impacts of these two drivers on fog dynamics, we employed a high‐resolution weather model and a full factorial design, excluding the effect of aerosols. Our results reveal that urbanization shifts the fog belt upward, reducing fog occurrence in lowlands while enhancing it at mid‐elevations. In contrast, warming‐induced circulation changes reduce fog in the west of the Central Mountain Range (CMR) but promote fog formation in the east. The complex interplay among local terrain, urbanization, and climate warming resulted in asymmetric changes in mountain fog, which can worsen the water stress differential between the western and eastern flanks of the CMR in Taiwan.