The climatic cyclicity in semiarid-arid central Asia over the past 500,000 years
The climatic cyclicity in semiarid-arid central Asia over the past 500,000 years
复制标题
过去50万年半干旱中亚的气候周期性
DOI：
10.1029/2011gl050202
复制
发表时间：
2012-01-13
影响因子：
5.2
通讯作者：
An, Z. S.
中科院分区：
文献类型：
--
作者：
Cheng, H.;Zhang, P. Z.;An, Z. S.
中亚目前是一个半干旱地区，西风带占主导地位。重要的是要了解这里的气候和降水变化的机制，因为该地区的水资源供应在今天和未来都至关重要。克桑洞石笋的高分辨率、绝对定年氧同位素（δ O-18）记录描述了过去50万年大部分时间的动态降水历史。这一记录表明，第一次，该地区的气候变化表现出一个游行的节奏与突然inceptions的低三角洲O-18洞穴沉积物的增长在高北方半球夏季日射，随后逐渐三角洲O-18增加，跟踪日射减少的时间。这些观察和解释与附近的解释形成对比，但海拔较高的冰芯记录。洞穴三角洲O-18的绝对定年位移可作为区域气候变化的年代学标志。与其他古气候记录相结合，Kesang观测表明，亚洲夏季季风降雨或相关水分可能入侵Kesang站点和/或邻近地区在高日照时间可能在改变该地区的轨道尺度水文学中发挥重要作用。根据我们的记录，只要人类活动的影响不取代自然过程，干旱气候将在今后几千年里在该地区占主导地位。引文：Cheng，H.，P.Z. Zhang C.，中国古猿科斯波特尔河L.爱德华兹，Y。J. Cai，D. Z. Zhang，W. C.桑，M。Tan和Z. S.安（2012），半干旱-干旱中亚过去50万年的气候周期性，地球物理学。保留信函：39，L01705，doi：10.1029/2011GL050202。
Central Asia is currently a semiarid-arid region, dominated by the Westerlies. It is important to understand mechanisms of climate and precipitation changes here, as water availability in the region is crucial today and in the future. High-resolution, absolutely-dated oxygen isotope (delta O-18) records of stalagmites from Kesang Cave characterize a dynamic precipitation history over most of the past 500,000 years. This record demonstrates, for the first time, that climate change in the region exhibits a processional rhythm with abrupt inceptions of low delta O-18 speleothem growth at times of high Northern Hemisphere summer insolation followed by gradual delta O-18 increases that track decreases of insolation. These observations and interpretations contrast with the interpretation of nearby, but higher elevation ice core records. The absolutely-dated cave delta O-18 shifts can be used to correlate the regional climate variability by providing chronological marks. Combined with other paleoclimate records, the Kesang observations suggest that possible incursions of Asian summer monsoon rainfall or related moisture into the Kesang site and/or adjacent areas during the high insolation times may play an important role in changing orbital-scale hydrology of the region. Based on our record, arid climate will prevail in this region for the next several millennia, providing that anthropogenic effects do not supersede natural processes. Citation: Cheng, H., P. Z. Zhang, C. Spotl, R. L. Edwards, Y. J. Cai, D. Z. Zhang, W. C. Sang, M. Tan, and Z. S. An (2012), The climatic cyclicity in semi-arid-arid central Asia over the past 500,000 years, Geophys. Res. Lett., 39, L01705, doi: 10.1029/2011GL050202.