The observed and simulated major summer climate features in northwest China and their sensitivity to land surface processes
The observed and simulated major summer climate features in northwest China and their sensitivity to land surface processes
复制标题
西北地区夏季主要气候特征的观测和模拟及其对地表过程的敏感性
DOI：
10.1007/s13351-014-4010-x
复制
发表时间：
2014-05
影响因子：
3.2
通讯作者：
Xue Yongkang
中科院分区：
文献类型：
--
作者：
Li Qian;Xue Yongkang
西北地区是典型的干旱半干旱区。本文分析了NWC夏季的主要气候特征，并对NCEP GCM/SSiB大气环流模式在该地区的表现进行了评价。模型采用卫星衍生的植被产品。通过与观测资料和Reanalysis II资料的比较，该模式基本捕获了NWC夏季能量平衡和环流的主要特征。这些特征包括：一个高表面温度中心主导着行星边界层；广泛的下降运动；一个位于对流层下层和中层（上层）的反气旋（气旋），覆盖北大陆架中部大部分地区；降水主要分布在NWC周围的高海拔地区。在特定土地覆盖变化条件下，评价了NWC及周边地区夏季能量平衡和环流对地表过程的敏感性。在敏感性试验中，除塔克拉玛干沙漠外，NWC大部分地区的退化使地表吸收辐射降低，地表热效应减弱。在北疆及周边地区，潜热减少导致低层反气旋环流和高层气旋环流异常增强，夏季降水减少，地表温度升高。同时，河西走廊干燥条件对潜热通量的影响较小。该地区以北的环流变化对间接改变低层气旋条件起主导作用，使辐合增多，垂直下降运动减弱，从而使该地区降水增加。
Northwest China (NWC) is a typical arid and semi-arid region. In this study, the main summer climate features over NWC are presented and the performance of an atmospheric general circulation model (NCEP GCM/SSiB) over this region is evaluated. Satellite-derived vegetation products are applied in the model. Based on comparison with observational data and Reanalysis II data, the model generally captures major features of the NWC summer energy balance and circulation. These features include: a high surface temperature center dominating the planetary boundary layer; widespread descending motion; an anticyclone (cyclone) located in the lower and middle (upper) troposphere, covering most parts of central NWC; and the precipitation located mainly in the high elevation areas surrounding NWC.The sensitivity of the summer energy balance and circulation over NWC and surrounding regions to land surface processes is assessed with specified land cover change. In the sensitivity experiment, the degradation over most parts of NWC, except the Taklimakan desert, decreases the surface-absorbed radiation and leads to weaker surface thermal effects. In northern Xinjiang and surrounding regions, less latent heating causes stronger anomalous lower-level anticyclonic circulation and upper-level cyclonic circulation, leading to less summer precipitation and higher surface temperature. Meanwhile, the dry conditions in the Hexi Corridor produce less change in the latent heat flux. The circulation change to the north of this area plays a dominant role in indirectly changing lower-level cyclonic conditions, producing more convergence, weaker vertical descending motion, and thus an increase in the precipitation over this region.
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DOI：
--
发表时间：
1984-06
期刊：
--
影响因子：
--
作者：
E. Matthews;E. Matthews
通讯作者：
E. Matthews;E. Matthews
DOI：
--
发表时间：
1998
期刊：
Plateau Meteorology
影响因子：
--
作者：
Z. Qiang
通讯作者：
Z. Qiang
影响因子：
--
作者：
Huang Rong
通讯作者：
Huang Rong
DOI：
--
发表时间：
2006
期刊：
Arid Meteorology
影响因子：
--
作者：
Dong An-xiang;Bai Hu-zhi;Lei Xiao-bin
通讯作者：
Dong An-xiang;Bai Hu-zhi;Lei Xiao-bin
影响因子：
4.9
作者：
T. Parish;D. Bromwich
通讯作者：
T. Parish;D. Bromwich