The Tibetan Plateau is an important heating source to the atmosphere, with great impacts on the weather, climate and environment systems in Asia and the Northern Hemisphere. The surface heating process of the plateau is therefore drawing attentions of the scientists and public. It’s generally believed that the Tibetan surface heating driven meridian circulation affects the onset and evolution of the South Asian summer monsoon. However, the monsoon hardly has feedback to the surface heating on the Tibetan Plateau due to the Himalayas blocking.  

More than half of the plateau surface is covered by giant mountain systems. In recent years, Professors ZOU Han, ZHOU Libo and their colleagues in the Institute of Atmospheric Physics, Chinese Academy of Sciences have been operating atmospheric experiments in the Himalayas region, and revealed the unique surface heating process in the Tibetan mountains and the negative feedback of the South Asian summer monsoon to the surface heating.  

They found that the complex topography in the Tibetan mountains traps great amount of solar energy, and gains a high surface temperature; and that the heat energy is transferred from the surface to the free atmosphere via the near surface turbulence and local circulation with much higher efficiency than the flat regions. This surface heating process is very sensitive to the input of solar energy, i.e., the strong solar radiation increases the surface heat energy, and enhances the upward heat transfer driven by the turbulence and local circulation, and vice versa.  

“The large cloud amount at high altitudes brought by the South Asian summer monsoon circulation efficiently blocks the solar radiation input,” Dr. ZOU explained, “It lowers the surface heat energy and weakens the heat energy transferred from the surface to the free atmosphere by the near surface turbulence and local circulation, and therefore depresses the surface heating in the Tibetan mountains.” 

The findings lead to a more comprehensive understanding on the Tibetan surface heating and its interaction with the neighboring climate systems.  

References   

Zhou, Libo, H. Zou, S. Ma, F. Li, J. Zhu, P. Li, and Y. Zhang (2015), The observed impacts of South Asian summer monsoon on the local atmosphere and the near-surface turbulent heat exchange over the Southeast Tibet, J. Geophys. Res. Atmos., 120, doi:10.1002/2014JD022928.   

Zhou, Libo, H. Zou, S. Ma, et al. (2012), Observed impact of the South Asian summer monsoon on the local meteorology in the Himalayas, Acta Meteor. Sinica, 26(2), 205-215, doi:10.1007/s13351-012-0206-0.   

Zou, Han, P. Li, S. Ma, L. Zhou, J. Zhu (2012), The local atmosphere and the turbulent heat transfer in the eastern Himalayas, Adv. Atmos. Sci., 29(3), 435–440, doi: 10.1007/s00376-011-0233-2.   

Zhou, Libo, H. Zou, S. P. Ma, P. Li, J. H. Zhu, and C. P. Huo (2011)，Vertical air mass exchange driven by the local circulation on the northern slope of Mount Everest, Adv. Atmos. Sci., 28(1), 217-222, doi: 10.1007/s00376-010-9231-z.    

Zou, Han, S. Ma, L. Zhou, P. Li, A. Li (2009), Measured turbulent heat transfer on the northern slope of Mt. Everest and its relation to the south Asian summer monsoon, Geophys. Res. Lett., VOL. 36, L09810, doi:10.1029/2008GL036984.   

Zhou, Libo, H. Zou, S. Ma, P. Li (2008), Study on impact of the South Asian summer monsoon on the down-valley wind on the northern slope of Mt. Everest, Geophys. Res. Lett., VOL. 35, L14811, doi:10.1029/2008GL034151.   

Zou, Han, L. Zhou, S. Ma, P. Li, W. Wang, A. Li, J. Jia, D. Gao (2008),Local wind system in the Rongbuk Valley on the northern slope of Mt. Everest, Geophys. Res. Lett., VOL. 35, L13813, doi:10.1029/2008GL033466. 

Contact: Dr. ZOU Han, zouhan@mail.iap.ac.cn