Dommo et al. (2025) Assessment of Anticipated Changes in Extreme Temperature and Precipitation Under 1.5°C and 2°C Warming Over the Mississippi River Basin

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

Identification

• Journal: International Journal of Climatology
• Year: 2025
• Date: 2025-10-02
• Authors: Atanas Dommo, Zachary Leasor, Anthony R. Lupo, Sherry L. Hunt, Noel Aloysius
• DOI: 10.1002/joc.70135

Research Groups

Information not available in the provided abstract.

Short Summary

This study analyzes projected changes in extreme precipitation and temperature indices over the Mississippi River Basin under 1.5°C and 2°C global warming scenarios and two Shared Socio-economic Pathways, finding an exacerbation of most extreme events, significant sensitivity to warming levels and emission scenarios, and a predominant contribution of internal climate variability to total uncertainty.

Objective

• To analyse the projected changes of extreme precipitation and temperature indices at 1.5°C and 2°C of warming over the Mississippi River Basin (MRB) under Shared Socio‐economic pathways (SSP) 2‐4.5 and SSP5‐8.5.

Study Configuration

• Spatial Scale: Mississippi River Basin (MRB) and its subregions.
• Temporal Scale: Projected changes at 1.5°C and 2°C global warming targets, using daily precipitation, minimum, and maximum temperature data.

Methodology and Data

• Models used: A set of 12 Coupled Models Intercomparison Project phase 6 (CMIP6) models; Bias Correction Constructed Analogues with Quantiles Mapping Reordering (BCCAQ) technique for downscaling.
• Data sources: Daily precipitation, minimum temperature, and maximum temperature outputs from CMIP6 models.

Main Results

• Changes in extreme precipitation (R95p) and temperature indices (TX90p, WSDI) are sensitive to warming targets and emission scenarios.
• Both 1.5°C and 2°C warming targets are expected to exacerbate very heavy rainfall (R95p) and intensify extreme precipitation and temperature overall.
• Cumulative wet days (CWD) are projected to decrease in many parts of the MRB under both warming targets and scenarios.
• Rainfall intensity (SDII) is projected to be more reduced under SSP5‐8.5 compared to SSP2‐4.5 with an additional 0.5°C warming.
• An additional 0.5°C climate warming (from 1.5°C to 2°C) is expected to:
  • Increase warm days (TX90p) and warm spell duration (WSDI) by 50% under SSP2‐4.5 and nearly 100% under SSP5‐8.5 over much of the MRB subregions.
  • Reduce extreme precipitation in the center of the MRB.
• Uncertainty in the magnitude of changes shows more than 75% contribution from internal climate variability to total variance, nearly 20% from climate models, and a marginal contribution from climate scenarios.
• The predominance of natural climate variability indicates decreased predictability in future extreme precipitation and temperature due to anthropogenic forcings, particularly at the regional scale.

Contributions

• Provides a detailed analysis of projected changes in key extreme precipitation and temperature indices over the Mississippi River Basin under specific 1.5°C and 2°C warming targets and two SSP scenarios (SSP2-4.5, SSP5-8.5).
• Quantifies the relative contributions of internal climate variability, climate models, and climate scenarios to the total uncertainty in future extreme event projections.
• Highlights the critical role of natural climate variability in regional predictability of extreme events, underscoring the need for improved understanding of local and regional climate drivers for future climate models.
• Identifies serious challenges to water availability, agriculture, crop yields, and ecosystems in the MRB due to projected climate warming.

Funding

Information not available in the provided abstract.

Citation

@article{Dommo2025Assessment,
  author = {Dommo, Atanas and Leasor, Zachary and Lupo, Anthony R. and Hunt, Sherry L. and Aloysius, Noel},
  title = {Assessment of Anticipated Changes in Extreme Temperature and Precipitation Under 1.5°C and 2°C Warming Over the Mississippi River Basin},
  journal = {International Journal of Climatology},
  year = {2025},
  doi = {10.1002/joc.70135},
  url = {https://doi.org/10.1002/joc.70135}
}