Cho et al. (2025) On the dynamic link between summer inner-continental warming and the outer-continental weakened precipitation extreme ascent in East Asia

Identification

• Journal: Atmospheric Research
• Year: 2025
• Date: 2025-11-22
• Authors: Jae Hee Cho, Hak‐Sung Kim
• DOI: 10.1016/j.atmosres.2025.108645

Research Groups

• Department of Environmental Education, Kongju National University, Gongju, Chungnam, Republic of Korea
• Department of Earth Science Education, Korea National University of Education, Cheongju, Chungbuk, Republic of Korea

Short Summary

This study elucidates the mechanism by which Arctic-cooling-induced inner-continental warming and anthropogenic aerosols suppressed July extreme precipitation in East Asia (eCYK) from 2013 to 2019. It reveals that these factors disrupted moisture transport and convective cloud formation, leading to a weakening of extreme precipitation events despite a general increase in summer precipitation.

Objective

• To elucidate the mechanism by which Arctic-cooling-induced inner-continental warming over East Asia suppressed July precipitation extremes in the outer-continental region encompassing eastern China, the Yellow Sea, and Korea (eCYK) during 2013–2019.

Study Configuration

• Spatial Scale: East Asia, specifically the outer-continental region (eastern China, Yellow Sea, Korea - eCYK) and the inner-continental region.
• Temporal Scale: July, during the period 2013–2019.

Methodology and Data

• Models used: WRF-Chem simulations
• Data sources: IMERG satellite data (precipitation), ERA5 reanalysis (large-scale circulation), Terra-MODIS observations (microphysical aerosol–cloud interactions and cloud properties)

Main Results

• A marked weakening of extreme ascent and associated drought conditions were observed in the eCYK region from 2013 to 2019, despite a general increase in summer precipitation and extreme events.
• This weakening was linked to pronounced Arctic cooling and intensified inner-continental warming.
• The warming-induced expansion of the upper-tropospheric Tibetan High strengthened the East Asian jet along its northern flank, while a southward intrusion of polar air created anomalous northwesterly flow over the eCYK region.
• This anomalous flow, amplified by indirect circulation, disrupted the transport of moisture from tropical oceans towards the rainy front.
• Terra-MODIS observations indicated reduced convective cloud formation, directly contributing to weaker precipitation extremes.
• WRF-Chem simulations showed that microphysical processes driven by anthropogenic aerosol indirect effects reduced precipitation by approximately 5.6 % across the eCYK region in July 2018.
• The combined impact of inner-continental warming and enhanced aerosol formation suppressed convective cloud development, leading to delayed onset and reduced intensity of extreme precipitation events.

Contributions

• Provides a comprehensive mechanism linking Arctic cooling, inner-continental warming, large-scale circulation changes, moisture transport, and microphysical aerosol–cloud interactions to the suppression of July extreme precipitation in East Asia.
• Quantifies the impact of anthropogenic aerosol indirect effects on precipitation reduction (approximately 5.6 % in July 2018).
• Highlights the complex interplay of multiple climate drivers contributing to regional precipitation anomalies during a specific recent period (2013–2019).

Funding

• Not specified in the provided text.

Citation

@article{Cho2025dynamic,
  author = {Cho, Jae Hee and Kim, Hak‐Sung},
  title = {On the dynamic link between summer inner-continental warming and the outer-continental weakened precipitation extreme ascent in East Asia},
  journal = {Atmospheric Research},
  year = {2025},
  doi = {10.1016/j.atmosres.2025.108645},
  url = {https://doi.org/10.1016/j.atmosres.2025.108645}
}