Document Type
Research-Article
Journal Name
Climate Dynamics
Keywords
Low-latitude highland, Soil temperature and moisture, Soil–atmosphere coupling, WRF model numerical simulation
Abstract
The low-latitude highland (LLH) of Southeast Asia is a hot spot of soil–atmosphere coupling, and variations in the soil temperature and moisture in this region have a significant effect on the regional climate. In this study, the characteristics of the soil–atmosphere coupling were analyzed, two decoupling numerical tests were designed, and the impacts of the soil temperature and moisture on the regional climate in the LLH were assessed. Finally, the key factors of the soil–atmosphere coupling were explored, and their contributions to air temperature and precipitation were evaluated. The primary conclusions are as follows. (1) The soil–atmosphere coupling in the LLH is primarily characterized by the soil moisture-limited regime in dry seasons (spring and winter) and the energy-limited regime in the wet seasons (summer and autumn), indicating that there is a seasonal difference in the soil–atmosphere coupling within the LLH. (2) The quantitative assessments conducted via numerical simulation revealed that the soil temperature–atmosphere coupling has the greatest impacts on the average air temperature and precipitation in winter and autumn, with changes of − 0.08 °C and 0.13 mm d−1 (35.5% and 1.4% variability), respectively. In contrast, the soil moisture–atmosphere coupling has the greatest impacts on the average air temperature and precipitation in summer, with changes of 0.20 °C and 0.13 mm d−1 (14.4% and − 3.0% variability), respectively. (3) Regarding the air temperature, the soil temperature mainly controls the net longwave radiation in the dry season and the net shortwave radiation in the wet season, with significant contributions exceeding 36.6%. The soil moisture regulates the sensible heat flux in both the dry and wet seasons, with significant contributions exceeding 32.8%. Regarding precipitation, both the soil temperature and moisture mainly affect evapotranspiration in the dry and wet seasons, with significant contributions exceeding 25.9%. © The Author(s) 2025.