Deng et al. (2025) Anthropogenic influences on rainfall seasonality changes and underlying physical mechanisms in global land monsoon regions

Identification

• Journal: Global and Planetary Change
• Year: 2025
• Date: 2025-12-14
• Authors: Shulin Deng, Xuanhua Song, Chunhua Lu, M. Lu, Tan Chen, Ni Yang
• DOI: 10.1016/j.gloplacha.2025.105253

Research Groups

• Key Laboratory of Environment Change and Resources Use in Beibu Gulf, (Nanning Normal University), Ministry of Education, Nanning 530001, China
• School of Geography and Planning, Nanning Normal University, Nanning 530001, China
• Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
• School of Management Science and Engineering, Guangxi University of Finance and Economics, Nanning 530003, China
• School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China
• School of Geography and Planning, Sun Yat-sen University, Guangzhou 510006, China

Short Summary

This study investigates how anthropogenic forcing influences rainfall seasonality changes and their underlying physical mechanisms in global land monsoon regions. It finds that enhanced rainfall seasonality in several key monsoon areas is confidently attributable to human activities, driven by varying contributions of greenhouse gases and aerosols affecting vertical moisture advection.

Objective

• To analyze the impacts of anthropogenic forcing on rainfall seasonality changes and their underlying physical mechanisms in global land monsoon regions.

Study Configuration

• Spatial Scale: Global land monsoon regions, with specific focus on South American, South African, North African, and South Asian monsoon regions.
• Temporal Scale: Recent decades (implied by "historical simulations" and "changes...during recent decades").

Methodology and Data

• Models used: Climate models (historical simulations), moisture budget analysis.
• Data sources: Observational data, historical climate model simulations.

Main Results

• Rainfall seasonality has significantly enhanced in the South American, South African, North African, and South Asian monsoon regions.
• This enhanced rainfall seasonality and the amplified risk of extreme seasonality in these regions are confidently attributed to anthropogenic forcing.
• The contributions of greenhouse gas (GHG) and anthropogenic aerosol (AER) forcings to rainfall seasonality changes vary across different regions.
• Moisture budget analysis reveals that either the GHG-forced thermodynamic term of vertical moisture advection, the AER-forced dynamic term of vertical moisture advection, or both, dominate the magnitudes and directions of rainfall trends during different parts of the local wet season, thereby altering rainfall concentration and magnitude, and ultimately enhancing rainfall seasonality.

Contributions

• Provides robust evidence attributing the enhanced rainfall seasonality in significant portions of global land monsoon regions to anthropogenic climate change.
• Elucidates the specific physical mechanisms (thermodynamic and dynamic terms of vertical moisture advection) through which GHG and AER forcings alter rainfall seasonality.
• Highlights the urgent need for both GHG and AER emissions reductions to mitigate future rainfall seasonality changes.

Funding

• Not specified in the provided text.

Citation

@article{Deng2025Anthropogenic,
  author = {Deng, Shulin and Song, Xuanhua and Lu, Chunhua and Lu, M. and Chen, Tan and Yang, Ni},
  title = {Anthropogenic influences on rainfall seasonality changes and underlying physical mechanisms in global land monsoon regions},
  journal = {Global and Planetary Change},
  year = {2025},
  doi = {10.1016/j.gloplacha.2025.105253},
  url = {https://doi.org/10.1016/j.gloplacha.2025.105253}
}