Global versus local effects on climate change in Asia
Global versus local effects on climate change in Asia
复制标题
DOI：
10.1007/s00382-014-2463-3
复制
发表时间：
2015-01
期刊：
影响因子：
4.6
通讯作者：
H. Paeth;Markus Müller;B. Mannig
中科院分区：
文献类型：
--
作者：
H. Paeth;Markus Müller;B. Mannig
区域气候变化产生于两个过程，在真实的气候系统中，这两个过程是不能相互分离的：局地辐射强迫和来自本身就受到气候变化影响的区域的气团平流。在这项研究中，我们提出了一个实验设计的区域气候模式的基础上，允许在亚洲的未来气候变化的全球和本地的影响进行评估。我们进行了两次运行，其特征是模型域内温室气体浓度不断增加，但其中一次（控制运行）单向嵌套在横向和海洋边界的全球控制运行中，而另一次（强制运行）是单向的。嵌套到一致强制的全球模拟中。目的是提高我们对区域范围内气候变化机制的认识。结果表明，亚洲的温度和降水变化确实主要与沿沿着横向边界进入的平流气团的变化有关。区域局限的温室效应只影响大气加热率，而降水和大气环流特征基本保持不变。强迫实验中的温度变化部分是由穿透横向边界的暖空气团决定的，部分是由大气环流过程的改变决定的，包括中亚上空双槽结构的趋势和温度平流的变化。降水的趋势模式在空间上更加不均匀，但可以部分归因于水平风散度和垂直速度的变化。
Regional climate change arises from two processes which, in the real climate system, cannot be separated from each other: local radiative forcing and advection of air masses from regions which themselves have been subject to climate change. In this study, we present an experimental design based on a regional climate model allowing for the assessment of global and local effects on future climate change in Asia. We carry out two runs which are characterized by increasing greenhouse gas concentrations within the model domain, but one (the control run) is one-way nested into a global control run at the lateral and oceanic boundaries while the other (the forced run) is one-way nested into a consistently forced global simulation. The aim is to improve our understanding of the mechanisms of climate change in a regional context. It turns out that temperature and precipitation changes in Asia are indeed mostly related to changes in the advected air masses which enter along the lateral boundaries. Regionally confined greenhouse forcing only affects the atmospheric heating rate while precipitation and atmospheric circulation features remain more or less unchanged. Temperature changes in the forced experiment are partly governed by warmer air masses penetrating the lateral boundaries and partly by a modification of atmospheric circulation processes, including a tendency towards a double-trough structure over Central Asia and changing temperature advection. The trend pattern of precipitation is much more heterogeneous in space but can partly be attributed to changes in horizontal wind divergence and vertical velocity.