EGU21-9077, updated on 21 Dec 2021
https://doi.org/10.5194/egusphere-egu21-9077
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Effect of surface heterogeneity on hyper-resolution simulation of soil moisture

Junhan Zeng1, Xing Yuan1, and Peng Ji2
Junhan Zeng et al.
  • 1Nanjing University of Information Science & Technology, Nanjing, Jiangsu Province, China
  • 2Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

Due to the land surface complexity, soil moisture immensely varies both spatially and temporally. However, the combined effects of land surface complexity and key hydrological processes (e.g., subsurface lateral flow) on fine-scale soil moisture heterogeneity remain elusive due to the scarcity of observations. Benefit from improvements in hyper-resolution land surface modeling, it provides an unprecedented opportunity to investigate the fine-scale soil moisture heterogeneity over a large region. Here, we use the Conjunctive Surface-Subsurface Process model version 2 (CSSPv2), which considers subsurface lateral flow, to perform hyperresolution (100-m) simulations over ten selected regions with different climate. We find that the heterogeneities of vegetation, soil texture, precipitation or their combinations increase soil moisture heterogeneity significantly (p<0.01). If only the topography heterogeneity presents, subsurface lateral flow increases the soil moisture heterogeneity significantly (p<0.01). However, the effect of subsurface lateral flow has been reduced by combining topography heterogeneity with other surface heterogeneities, with a few regions showing decreased soil moisture heterogeneity mainly because of the combined effect of subsurface lateral flow and soil texture heterogeneity. This study suggests that soil texture heterogeneity does not necessarily interact synergistically with physical processes (e.g., subsurface lateral flow) for increasing soil moisture heterogeneity, although they can increase the heterogeneity separately.

How to cite: Zeng, J., Yuan, X., and Ji, P.: Effect of surface heterogeneity on hyper-resolution simulation of soil moisture, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9077, https://doi.org/10.5194/egusphere-egu21-9077, 2021.