Duan Anmin, Xiao Zhixiang
State Key Laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences (CAS), Beijing 100029, China.
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science &Technology, Nanjing 210044, China.
Sci Rep. 2015 Sep 2;5:13711. doi: 10.1038/srep13711.
The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China, and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998-2013 (0.25 °C decade(-1)), compared with that during 1980-1997 (0.21 °C decade(-1)). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud-radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998, and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud-radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau.
基于1980年至2013年的历史观测数据确定了青藏高原的地面气温变化。与中国其他地区的降温趋势以及20世纪90年代后的全球变暖停滞情况相反,1998 - 2013年期间青藏高原出现了加速变暖趋势(0.25 °C/十年),相较于1980 - 1997年期间(0.21 °C/十年)。进一步的结果表明,这种加速变暖趋势在一定程度上可能归因于云辐射反馈。青藏高原北部夜间云量增加会通过增强大气逆辐射使夜间温度升高,而青藏高原南部白天云量减少会导致白天日照时长增加,从而使地面气温升高。同时,自1998年以来原地地面风速逐渐恢复,因此能量集中无法解释20世纪90年代后青藏高原的加速变暖趋势。研究表明,云辐射反馈可能在调节青藏高原近期的加速变暖趋势中发挥重要作用。