Abeysingha et al. (2026) Drought pattern under climate change in Harris County, Texas, USA based on CMIP6 projections

Identification

• Journal: Scientific Reports
• Year: 2026
• Date: 2026-03-25
• Authors: N. S. Abeysingha, Ram L. Ray, Kusalika M. Kularathna, D. M. B. M. Deegala
• DOI: 10.1038/s41598-026-42547-3

Research Groups

• College of Agriculture, Food and Natural Resources, Prairie View A&M University, Prairie View, TX, USA
• Department of Agricultural Engineering and Soil Science, Faculty of Agriculture, Rajarata University of Sri Lanka, Anuradhapura, Sri Lanka

Short Summary

This study assessed future drought conditions in Harris County, Texas, using CMIP6 GCMs under various SSP scenarios for 2026–2085, revealing a substantial projected increase in drought frequency, intensity, and severity, especially in the far-future (2056–2085).

Objective

• To assess future drought conditions in Harris County, Texas, under climate change using Coupled Model Intercomparison Project Phase 6 (CMIP6) projections and different Shared Socioeconomic Pathway (SSP) scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) for the period 2026–2085.

Study Configuration

• Spatial Scale: Harris County, Texas, USA.
• Temporal Scale:
  • Future period: 2026–2085 (with a specific focus on the far-future period of 2056–2085).
  • Historical periods for comparison: 1980–2002 and 2003–2024.

Methodology and Data

• Models used:
  • Five Coupled Model Intercomparison Project Phase 6 (CMIP6) General Circulation Models (GCMs).
  • Shared Socioeconomic Pathway (SSP) scenarios: SSP1-2.6 (low emissions), SSP2-4.5 (medium emissions), and SSP5-8.5 (high emissions).
  • Drought indices: Standardized Precipitation Evapotranspiration Index (SPEI) at 6-month (SPEI-6) and 12-month (SPEI-12) timescales.
  • Statistical tests: Mann-Kendall trend test (implied by trend analysis), significance testing (p < 0.05).
  • Analysis: Severity Duration Frequency (SDF) curve analysis.
• Data sources: NEX-GDDP-CMIP6 and Daymet repositories.

Main Results

• A substantial increase in drought frequency, intensity, and severity is projected for Harris County, particularly during the far-future period (2056–2085).
• An oscillating drought pattern was identified: high frequency (1980–2002), temporary reduction (2003–2024), and projected intensification (2056–2085).
• Under medium (SSP2-4.5) and high (SSP5-8.5) emission scenarios, both SPEI-6 and SPEI-12 exhibit significant (p < 0.05) negative trends across the ensemble mean and most individual GCMs for the future period, contrasting with slight positive trends observed in the historical period.
• Severity duration frequency curve analysis indicates that future droughts under SPEI-12 will be significantly more severe across all return periods (ranging from 2 years to 50 years).
• The study projects a doubling of drought frequency under the high emission scenario (SSP5-8.5).

Contributions

• Provides comprehensive, region-specific insights into future drought risk for Harris County, Texas, under various climate change scenarios using advanced CMIP6 projections.
• Identifies a critical threshold for regional water security due to the projected intensification and doubling of drought frequency, particularly under high emission scenarios.
• Offers crucial information for policymakers, emphasizing the urgent need for proactive planning and adaptation strategies to address future water security challenges in the region.
• Utilizes multi-scalar SPEI and SDF curve analysis to provide a robust characterization of future drought characteristics (frequency, intensity, severity, duration).

Funding

• Natural Resources and Conservation Services (NRCR), United States Department of Agriculture (USDA) [grant number: NR237442XXXXC023].

Citation

@article{Abeysingha2026Drought,
  author = {Abeysingha, N. S. and Ray, Ram L. and Kularathna, Kusalika M. and Deegala, D. M. B. M.},
  title = {Drought pattern under climate change in Harris County, Texas, USA based on CMIP6 projections},
  journal = {Scientific Reports},
  year = {2026},
  doi = {10.1038/s41598-026-42547-3},
  url = {https://doi.org/10.1038/s41598-026-42547-3}
}