The huge thermal and dynamic effects of the Tibetan Plateau (TP) and the adjacent Iranian Plateau have a significant impact on the surrounding atmosphere and oceans regions, and can extend to the globe as well. A review published in National Science Review summarized recent findings of a 10-year National Natural Science Foundation of China project entitled “The earth-atmosphere coupling system on the Qinghai-Tibet Plateau and its global climate effect”, launched in 2013.

The review, written by scientists from Institute of Atmospheric Physics at Chinese Academy of Sciences, Sun Yat-sen University, and Peking University， comprehensively summarized the studies during the past 6 years, and illustrated the formation of the Tibetan Plateau and Iranian Plateau (TIP) dynamical coupling system and its impact on the surrounding regions and the North Hemisphere climate. They also documented the mechanism that the TIP and ocean collaborative influence the Asian climate.

The paper revealed that the land-air coupling system in the Asian summer monsoon region is composed by the surface elevated heating over Tibetan Plateau and Iranian Plateau, the water vapor transport in the South Asian monsoon regions, and the condensation heating of the monsoon precipitation. The heating effect of TIP lifted the tropopause aloft, forms the anticyclonic circulation nearby with the temperature anomaly of upper colder and lower warmer. This pattern triggers the meridional monsoon circulation, and provides the large-scale ascending circulation background for the formation and maintenance of the Asian summer monsoon.

Clouds over Tibetan Plateau. (Image by HE Bian)

The team found the surface heating anomaly over TP during boreal summer could not only impact the Asian climate, but also impact the regional distribution of global atmospheric circulation anomaly. The "southern flood and northern drought" pattern over East Asia during the late 20’s century and the wet in the South China mainland/dry in the north India pattern, etc. are all related with the weakness of the TP surface thermal forcing. The TP could influence the Atlantic meridional overturning circulation (AMOC) through air-sea interactions. The air-sea coupled model experiments proved that the forcing of TP could influence the sea surface temperature and salinity through the quasi-stationary wave in the atmosphere, circulation in the ocean and the air-sea interaction process.

"We hope our findings can contribute to understanding of the influence of TP on the regional and global climate change." Said Prof. LIU Yimin, the lead author of the review.

Reference：
Yimin Liu, Mengmeng Lu, Haijun Yang, Anmin Duan, Bian He, Song Yang, Guoxiong Wu, Land–atmosphere–ocean coupling associated with the Tibetan Plateau and its climate impacts, National Science Review, Volume 7, Issue 3, March 2020, Pages 534–552, https://doi.org/10.1093/nsr/nwaa011

Media contact: Ms. LIN Zheng, jennylin@mail.iap.ac.cn