Zhang et al. (2026) Why Does a Shallow Land Model Underestimate the Dryland Drying Trends?

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Geophysical Research Atmospheres
• Year: 2026
• Date: 2026-08-11
• Authors: Xue‐Yan Zhang, Xubin Zeng, Zhi Li, Yuan Qiu, Guo‐Yue Niu
• DOI: 10.1029/2026jd046571

Research Groups

• Hydrology Department, University of [Name]
• Earth System Science Laboratory, National Institute for Environmental Studies

Short Summary

This study improves the representation of terrestrial water storage declines in global drylands by incorporating deeper soils into a land surface model, leading to more accurate simulations and highlighting potential biases in groundwater assessments based on GRACE data.

Objective

• Investigate the impact of soil depth on simulating terrestrial water storage declines in global drylands using advanced soil hydrology and plant hydraulics.

Study Configuration

• Spatial Scale: Global drylands (regions with low precipitation and high evapotranspiration)
• Temporal Scale: Long-term (annual to decadal) trends

Methodology and Data

• Models used: Noah-MP with advanced soil hydrology and plant hydraulics
• Data sources: GRACE satellite data, global data set of depth to bedrock, observation-based datasets for validation

Main Results

• Deeper soils enhance evapotranspiration supported by capillary rise and greater deep root water uptake of stored antecedent precipitation.
• Simulated dryland drying trends are dominated by groundwater storage changes rather than soil moisture changes.

Contributions

• The study provides new insights into the role of deeper soils in simulating terrestrial water storage declines, highlighting potential biases in GRACE-based groundwater assessments.
• The results suggest that incorporating deeper soils into land surface models can improve their ability to reproduce observed drying trends across global drylands.

Funding

• This research was supported by the National Science Foundation (Award # [Number]) and the Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research [Number]).

Citation

@article{Zhang2026Why,
  author = {Zhang, Xue‐Yan and Zeng, Xubin and Li, Zhi and Qiu, Yuan and Niu, Guo‐Yue},
  title = {Why Does a Shallow Land Model Underestimate the Dryland Drying Trends?},
  journal = {Journal of Geophysical Research Atmospheres},
  year = {2026},
  doi = {10.1029/2026jd046571},
  url = {https://doi.org/10.1029/2026jd046571}
}