Liu et al. (2026) Spatiotemporal characteristics and onset processes of flash droughts during the growing season in Inner Mongolia, China

Identification

• Journal: Journal of Mountain Science
• Year: 2026
• Date: 2026-01-01
• Authors: Hongyu Liu, Yunhu Xie, Gesi Tang
• DOI: 10.1007/s11629-025-9498-2

Research Groups

• College of Geographical Sciences, Inner Mongolia Normal University, Hohhot, China
• College of Ecology and Environment, Baotou Teachers’ College, Baotou, China

Short Summary

This study investigated the spatiotemporal characteristics and onset processes of flash droughts in Inner Mongolia, China, from 1982 to 2022, identifying five hotspot regions and determining that vapor pressure deficit is consistently the most influential meteorological driver.

Objective

• To investigate the spatiotemporal characteristics and development mechanisms of flash droughts (FDs) in Inner Mongolia, China, and to assess the roles of key meteorological drivers in driving soil moisture variability.

Study Configuration

• Spatial Scale: Inner Mongolia, China, with specific focus on five hotspot regions: southern Alxa Plateau, Hetao Plain in Bayannur, northwestern Xilingol Plain, western Liaohe River Plain, and northern Da Hinggan Ling.
• Temporal Scale: Growing seasons from 1982 to 2022 (41 years).

Methodology and Data

• Models used: Flash drought events were identified using root-zone soil moisture data. XGBoost was likely used for analyzing the influence of meteorological drivers, as indicated by keywords and the analysis of dominant drivers.
• Data sources: Root-zone soil moisture data, precipitation, evapotranspiration, temperature, potential evapotranspiration, incoming solar radiation, and vapor pressure deficit.

Main Results

• Five flash drought hotspot regions were identified: southern Alxa Plateau, Hetao Plain in Bayannur, northwestern Xilingol Plain, western Liaohe River Plain, and northern Da Hinggan Ling.
• Over the 41-year study period, an average of 7.44 flash drought events occurred across the study area.
• The mean duration of flash droughts was 9.17 pentads (approximately 45.85 days), exhibiting a significant increasing trend of 0.39 pentads per decade.
• Flash drought onsets primarily lasted for 2–3 pentads (10–15 days).
• During the flash drought development phase, precipitation and evapotranspiration decreased, while temperature, potential evapotranspiration, incoming solar radiation, and vapor pressure deficit increased.
• Vapor pressure deficit was consistently the most influential meteorological factor driving flash drought development, although the dominant drivers showed spatial heterogeneity across hotspot regions.

Contributions

• The findings improve the understanding of climate drivers at different stages of flash drought development.
• Provides scientific support for early warning and prevention of droughts in Inner Mongolia.

Funding

• Inner Mongolia Autonomous Region Natural Science Foundation Youth Fund Project (Grants No.2024QN04020)
• Science and technology program of Inner Mongolia Autonomous Region (Grants No.2022YFDZ0027)

Citation

@article{Liu2026Spatiotemporal,
  author = {Liu, Hongyu and Xie, Yunhu and Tang, Gesi},
  title = {Spatiotemporal characteristics and onset processes of flash droughts during the growing season in Inner Mongolia, China},
  journal = {Journal of Mountain Science},
  year = {2026},
  doi = {10.1007/s11629-025-9498-2},
  url = {https://doi.org/10.1007/s11629-025-9498-2}
}