Dong et al. (2025) Intensification of extreme cold events in East Asia in response to global mean sea-level rise

Identification

• Journal: Nature Communications
• Year: 2025
• Date: 2025-09-30
• Authors: Caoyi Dong, Zhongshi Zhang, Noel Keenlyside, Stefan Sobolowski, Odd Helge Otterå, Antonio Bonaduce, Jiping Xie, Roshin P. Raj, Yong Liu, Bo Liu, Mingna Wu
• DOI: 10.1038/s41467-025-63727-1

Research Groups

• Department of Atmospheric Science, School of Environmental Studies, China University of Geoscience, Wuhan, China
• Centre for Severe Weather and Climate and Hydro-geological Hazards, Wuhan, China
• Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
• School of Geographic Science, Nantong University, Nantong, China
• State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, P.R. China
• Geophysical Institute, University of Bergen, Bergen, Norway
• Nansen Environmental and Remote Sensing Centre, Bjerknes Centre for Climate Research, Bergen, Norway
• NORCE Norwegian Research Centre, Bjerknes Centre for Climate Research, Bergen, Norway
• Centre for Early Sapiens Behaviour, University of Bergen, Bergen, Norway
• Plateau Atmosphere and Environment Key Laboratory of Sichuan Province, School of Atmospheric Sciences, University of Information Technology, Chengdu, China

Short Summary

This study investigates the impact of global mean sea-level (GMSL) rise on winter extreme cold events in East Asia using climate model experiments. The findings demonstrate that GMSL rise promotes stronger and more frequent extreme cold events by altering atmospheric circulation, a phenomenon expected to intensify in the coming century.

Objective

• To investigate the effects of global mean sea-level (GMSL) rise on winter cold extremes in East Asia using climate model experiments.

Study Configuration

• Spatial Scale: East Asia (focused region), Eurasia (blocking events), Northern Hemisphere (atmospheric responses), global (GMSL rise). Model horizontal resolution: atmosphere-land grid at 2°, ocean-sea-ice at a nominal 1° (approximately 40 km at high northern latitudes).
• Temporal Scale: Coupled sea-level experiments run for 2200 model years, with analysis focused on the last 200 years. Atmosphere-only experiments run for 45 years, with analysis focused on the final 40 years. Focus on winter (December, January, February).

Methodology and Data

• Models used: NorESM1-F (Norwegian Earth System Model family), which is based on the Community Climate System Model, version 4 (CCSM4), and NorESM1-M. Atmosphere-only experiments utilized the Community Atmosphere Model, version 4 (CAM4).
• Data sources:
  • Coupled sea-level sensitivity experiments (8 different GMSL rise levels: 0.15 m, 0.3 m, 0.625 m, 1.25 m, 2.5 m, 5 m, 10 m, 20 m), a pre-industrial (PI) control run, and an experiment without sea-level rise (SL0m).
  • Atmosphere-only experiments forced by climatological sea surface temperature (SST) annual cycle from the CO2400 experiment, with added winter monthly average North Pacific SST anomalies from coupled experiments.
  • Atmosphere-only experiment to assess regional sea-level anomalies derived from satellite altimetry-based sea surface height data (1993–2023).
  • Self-Organizing Maps (SOM) for clustering atmospheric circulation patterns.
  • Gradient-reversal (REV) indices for identifying atmospheric blocking events.

Main Results

• Global mean sea-level (GMSL) rise promotes stronger and more frequent winter extreme cold events (ECDs) in East Asia, with a non-linear relationship between GMSL rise and ECD intensification.
• This intensification is primarily attributed to weakened mid-high latitude westerly winds and an increased occurrence of blocking events over Eurasia.
• Specific synoptic patterns (e.g., SOM1, related to high-latitude European, Ural, and Okhotsk blockings) that favor ECDs show increased frequency and maximum persistence with GMSL rise.
• The weakening of westerly winds is linked to significant warming in the North Pacific, which generates positive geopotential height anomalies and triggers eastward-propagating Rossby waves.
• Changes in large-scale atmospheric circulations strengthen poleward atmospheric energy transport, contributing to regional Arctic warming while cooling the East Asian troposphere, further weakening westerly winds and enhancing blocking events.
• The polar vortex shifts towards North America and away from the Eurasian continent, further promoting blocking events and enhancing cold air intrusion in East Asia.
• Atmosphere-only experiments confirm that North Pacific warming is a key mechanism driving the intensification of ECDs, decreased westerly winds, and increased blocking events in Eurasia.

Contributions

• Provides the first evidence that even a slight, globally uniform sea-level rise can significantly modify synoptic systems and intensify extreme weather events, specifically winter cold extremes in East Asia.
• Highlights that the threats arising from GMSL rise are not limited to coastal regions but extend to inland areas.
• Elucidates the underlying mechanisms: GMSL rise leads to North Pacific warming, which triggers Rossby waves, weakens mid-high latitude westerly winds, increases Eurasian blocking events, enhances poleward atmospheric energy transport, and shifts the polar vortex, all contributing to more severe East Asian cold extremes.
• Demonstrates a non-linear relationship between the response of winter extreme cold events and the magnitude of GMSL rise.
• Suggests an urgent need for global disaster risk assessment stemming from sea-level rise, considering its complex and far-reaching impacts.

Funding

• National Natural Science Foundation of China (grant no. 42125502)
• SapienCE (project no. 262618)
• Norwegian Research Council (projects nos. 314371, 229819, and 221712)
• Notur/Norstore projects (NN9133/NS9133, NN9486/NS9486, and NN9874/NS9874)
• Department of Atmospheric Science, China University of Geosciences (CUG)

Citation

@article{Dong2025Intensification,
  author = {Dong, Caoyi and Zhang, Zhongshi and Keenlyside, Noel and Sobolowski, Stefan and Otterå, Odd Helge and Bonaduce, Antonio and Xie, Jiping and Raj, Roshin P. and Liu, Yong and Liu, Bo and Wu, Mingna},
  title = {Intensification of extreme cold events in East Asia in response to global mean sea-level rise},
  journal = {Nature Communications},
  year = {2025},
  doi = {10.1038/s41467-025-63727-1},
  url = {https://doi.org/10.1038/s41467-025-63727-1}
}