The CO2-induced sensible heat changes over the Tibetan Plateau from November to April
The CO2-induced sensible heat changes over the Tibetan Plateau from November to April
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DOI：
10.1007/s00382-019-04887-x
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发表时间：
2019-11
期刊：
影响因子：
4.6
通讯作者：
X. Qu;G. Huang;Lihua Zhu
中科院分区：
文献类型：
--
作者：
X. Qu;G. Huang;Lihua Zhu
利用耦合模式相互比较项目（CMIP 5）的月输出资料，分析了CO2的直接和间接效应对青藏高原感热响应的贡献。在全球变暖的背景下，11 - 4月（NDJFMA）的TP和SH呈均匀增加的趋势。在NDJFMA期间，TP上的SH变化主要归因于CO2增加引起的SST均匀增加。这种均匀的SST增加使大气变暖。反过来，它导致：（1）青藏高原降雪量减少，以南坡最大;（2）青藏高原以南3000 m海拔高度以上的融雪量增加，3000 m海拔以下的融雪量减少。降雪和融雪的净效应是朝着减少的积雪覆盖的TP，这可能会改变雪的反馈。因此，更多的太阳辐射被TP表面吸收，TP表面变暖。地面空气温差增大，导致SH增大。此外，SH的增强抵消了吸收的太阳辐射的增加，并平衡了辐射收支。在上述过程中，SST型对TP和SH的增加有一定的抵消作用，CO2直接辐射效应和残差项的贡献相对较小。在海拔不低于3000 m的网格上，平均变化基本上是线性的。
Based on the monthly outputs of the Couple Model Intercomparison Project phase 5 (CMIP5), the present study examines the contributions of direct and indirect effects of CO2to the response of the sensible heat (SH) over the Tibetan Plateau (TP). Under global warming, the TP SH features an uniform increase during November–April (NDJFMA). During NDJFMA, the SH change over the TP can be mainly attributed to the uniform SST increase induced by CO2increasing. This uniform SST increase warms the atmosphere. In turn, it leads to: (1) reduction in snowfall over the TP, with maximum over south TP; (2) increased snowmelt mainly above 3000 m and decreased snowmelt near or south of 3000 m elevation south of TP. The net effects of snowfall and snowmelt are towards the reduction of the snow cover over the TP, which may alter the snow-albedo feedback. Consequently, more solar radiation is absorbed by the TP surface, and the TP surface warms. The surface–air temperature difference increases, which leads to the increase in SH. In addition, the enhancement of the SH offsets the increase in absorbed solar radiation and balances the radiation budget. On the above processes, the SST pattern slightly cancels out the TP SH increase; the contributions of CO2direct radiative effect and residual terms are relatively small. Over the grids with elevations no less than 3000 m, the averaged changes are generally linear.