Liu et al. (2026) SPEI-Based Drought Frequency, Intensity, and Duration from CMIP6 Models Under SSP1-2.6 and SSP5-8.5 Across Tropical–Subtropical Monsoon Asia

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

Identification

• Journal: Water
• Year: 2026
• Date: 2026-07-18
• Authors: Maochou Liu, Wenxiang Wu, Ziyi Zhang, Xinshuai Ren, Ke Wang, Jiahui Cheng, Bo Yang, Jin Geng
• DOI: 10.3390/w18141745

Research Groups

Not specified in the provided text.

Short Summary

This study evaluates future drought risk in tropical-subtropical monsoon Asia using CMIP6 models, concluding that while low-emission scenarios (SSP1-2.6) can stabilize moisture regimes, high-emission scenarios (SSP5-8.5) will lead to pervasive intensification and expansion of drought.

Objective

• To determine the regional patterns and the dependence of drought risk on emission scenarios in tropical-subtropical monsoon Asia under future warming.

Study Configuration

• Spatial Scale: Tropical-subtropical monsoon Asia.
• Temporal Scale: 2015–2100.

Methodology and Data

• Models used: 14-member CMIP6 multi-model ensemble (NEX-GDDP-CMIP6 dataset).
• Data sources: NEX-GDDP-CMIP6.
• Analysis Tools: 3-month Standardized Precipitation Evapotranspiration Index (SPEI-3), event-based run theory, and Mann–Kendall trend analysis.
• Evaluated Dimensions: Annual mean SPEI, frequency, intensity, duration, and regional drought area.

Main Results

• Current State: A west-to-east moisture gradient exists, with chronic deficits in southwestern China, southern Myanmar, and Thailand, and surpluses in southeastern China and the equatorial belt.
• Scenario Comparison:
  • SSP1-2.6: No statistically significant trends observed across the evaluated metrics.
  • SSP5-8.5: Robust drying trends; 8.0% of the region shows significant SPEI declines and up to 30.9% exhibits significant intensification.
• Quantitative Shifts: Negative SPEI anomalies are projected to deepen by 0.2–0.4 units.
• Uncertainty Analysis: Scenario uncertainty surpasses model structural uncertainty at different time horizons: intensity (2067), area (2078), duration (2079), and frequency (2090).

Contributions

• Provides a comprehensive assessment of drought risk across four dimensions (mean, frequency, intensity, duration) in a highly biodiverse and populous region.
• Quantifies the specific timing when emission scenario uncertainty becomes the dominant driver over model structural uncertainty for different drought metrics.

Funding

Not specified in the provided text.

Citation

@article{Liu2026SPEIBased,
  author = {Liu, Maochou and Wu, Wenxiang and Zhang, Ziyi and Ren, Xinshuai and Wang, Ke and Cheng, Jiahui and Yang, Bo and Geng, Jin},
  title = {SPEI-Based Drought Frequency, Intensity, and Duration from CMIP6 Models Under SSP1-2.6 and SSP5-8.5 Across Tropical–Subtropical Monsoon Asia},
  journal = {Water},
  year = {2026},
  doi = {10.3390/w18141745},
  url = {https://doi.org/10.3390/w18141745}
}