This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:

fact-checked

peer-reviewed publication

trusted source

proofread

Climate models predict weakened subtropical circulation in stable warming scenario

Weakening subtropical circulation under greenhouse warming
Seasonal changes in subtropical circulation under greenhouse warming. a, b Changes in the 850 hPa streamfunction (shading) in the Shared Socioeconomic Pathway 5-8.5 (SSP5-8.5) experiment relative to the historical experiment during a the boreal winter (December–February; DJF) and b the boreal summer (June–August; JJA). The contours in a and b represent the climatology of the 850 hPa streamfunction in the historical experiment (interval: 5 × 106 m2 s−1). Hatching indicates that the change is robust. Credit: Nature Communications (2024). DOI: 10.1038/s41467-023-44244-5

The latest climate models show a weakening of the subtropical circulation under stable greenhouse warming scenario, according to a new study published in Nature Communications.

The low-level subtropical atmospheric , which includes over land and high-pressure zones over the ocean, plays a pivotal role in shaping the climate, ecosystems, and societies of the surrounding regions.

The study, conducted jointly by researchers from the Institute of Atmospheric Physics of the Chinese Academy of Sciences and Yunnan University, explored various future carbon emission scenarios and uncovered two key drivers behind the changes in the subtropical circulation: The land-sea thermal contrast due to the direct effect of CO2 and surface warming.

These two factors work on distinct time scales. That is, the thermal contrast strengthens the circulation most significantly in the beginning, while the diminishing effect caused by surface warming unfolds gradually.

"The varying contributions of these two factors in different scenarios lead to different results in the model projections. However, in a more stable warming scenario, the subtropical circulation is expected to weaken significantly," said Prof. Huang Ping, corresponding author of the study.

The researchers used cutting-edge climate models to assess changes in the intensity of the lower-level subtropical atmospheric circulation due to greenhouse warming. The results show that the weakened subtropical circulation implies a reduced monsoon range and increased dryness at the edges of arid regions under a stable scenario.

Meanwhile, accurate projections of near-term changes in the subtropical circulation require a thorough consideration of greenhouse gas emission trajectories and the timescales of two key drivers.

"The finding is also helpful in understanding changes in the subtropical circulation in specific regions where large uncertainties remain in the current knowledge," said Dr. Zhou Shijie, lead author of the study.

More information: Shijie Zhou et al, Robust changes in global subtropical circulation under greenhouse warming, Nature Communications (2024). DOI: 10.1038/s41467-023-44244-5

Journal information: Nature Communications

Citation: Climate models predict weakened subtropical circulation in stable warming scenario (2024, January 18) retrieved 19 July 2024 from https://phys.org/news/2024-01-climate-weakened-subtropical-circulation-stable.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

Climate change in the South China Sea found to have global impacts on weather patterns

13 shares

Feedback to editors