| 引用本文: | 张占森,李育,高铭君,周雪如,李海烨,段俊杰,薛雅欣.2025.青藏高原东北缘现代尺度与全新世千年尺度气候变化的联系与启示【封面文章】[J].地球环境学报,16(2):135-151 |
| ZHANG Zhansen,LI Yu,GAO Ming jun,ZHOU Xueru,LI Haiye,DUAN Junjie,XUE Yaxin.2025.The relationship and enlightenment between the modern scale and the Holocene millennium-scale climate change in the northeastern margin of the Qinghai-Xizang Plateau【Cover】[J].Journal of Earth Environment,16(2):135-151 |
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| 摘要: |
| 青藏高原东北缘是我国最重要的生态功能区和淡水补给区，研究其不同时间尺度气候变化过程及机理可以为区域环境演变评估提供参考依据和科学支撑。通过系统分析气象观测、气候模拟和古气候记录数据，回顾青藏高原东北缘现代尺度与全新世千年尺度的气候变化特征，总结不同时间尺度上气候变化的影响因素，重点归纳热带海洋对青藏高原东北缘气候变化的影响机制。研究表明：青藏高原东北缘在现代尺度上呈现明显的暖湿化趋势，干湿变化主要受海洋活动、北极海冰和高原积雪的影响。全新世早期和中期青藏高原东北缘气候较为湿润，晚全新世以干旱为主要特征，千年尺度上干湿变化受控于低纬度太阳辐射和热带太平洋的海洋表面温度（sea surface temperature，SST）。热带海洋对该区域干湿变化的影响程度在不同时间尺度均较大，而其他因素存在时间尺度效应。随着未来全球气候变化的加剧，海洋活动充满不确定性，将会加剧区域生态安全风险。 |
| 关键词: 青藏高原东北缘 气候变化 现代尺度 千年尺度 海洋活动 |
| DOI：10.7515/JEE232034 |
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| 基金项目:国家自然科学基金项目（42371159）；第二次青藏高原综合科学考察研究（2019QZKK0202） |
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| The relationship and enlightenment between the modern scale and the Holocene millennium-scale climate change in the northeastern margin of the Qinghai-Xizang Plateau【Cover】 |
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ZHANG Zhansen, LI Yu*, GAO Ming jun, ZHOU Xueru, LI Haiye, DUAN Junjie, XUE Yaxin
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College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
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| Abstract: |
| Background, aim, and scope The northeastern margin of the Qinghai-Xizang Plateau is one of the most crucial ecological function area and freshwater supply area in China. Studying the dryness and wetness changes on the modern scale and the Holocene millennial scale in this region, exploring the driving mechanisms of climate change on different time scales, and conducting a comparative study on the connections and difference between the modern scale and the millennial scale are of great significance. Such research can offer reference and scientific support for assessing regional environmental evolution. In this study, based on modern meteorological observations, paleoclimatic records and climate simulation data, the climate changes in the northeastern margin of the Qinghai-Xizang Plateau since the Holocene were analyzed, and the main factors affecting climate change at different time scales were identified. Materials and methods In this study, meteorological elements, proxy records, and model data from published papers and databases were collected and analyzed. Empirical Orthogonal Function (EOF) and Pearson correlation analysis were employed to explore the leading factors influencing climate at different time scales. Results On the modern scale, the precipitation on the northeastern margin of the Qinghai-Xizang Plateau shows significant north-south differences. The overall environment is relatively arid, yet the trend of warming and humidification is evident. The regional modern-scale wet and dry changes are influenced by ocean activities, Arctic sea ice and plateau snow cover, and are not directly associated with solar activity. On the millennium scale of the Holocene, the climate in the northeastern margin of the Qinghai-Xizang Plateau was humid in the early and mid-Holocene. A suitable climate emerged in the mid-Holocene, and the climate in the late Holocene was generally dry. The millennium-scale wet and dry changes are controlled by low-latitude solar radiation and tropical Pacific SST. Discussion Although the northeastern margin of the Qinghai-Xizang Plateau is located in the continent’s hinterland, the influence of the tropical ocean on the region’s dryness and humidity changes is relatively large both on the modern scale and the Holocene millennium scale. The SST anomaly in the tropical Pacific plays a vital role in the dryness and wetness of the East Asian monsoon marginal region on different time scales. When an El Niño event occurs, the sea temperature in the tropical eastern Pacific rises abnormally. This leads to changes in the atmospheric circulation system, weakening of the southeast trade winds and equatorial ocean currents, weakening of the Walker circulation, and eastward movement of the ascending branch. As a result, precipitation in the monsoon margin decreases, leading to a dry climate. When the sea temperature in the tropical western Pacific rises and the tropical eastern Pacific cools, the equatorial cyclone and convective activities in the Philippine waters will increase. Moreover the subtropical high pressure in the western Pacific will move northward. This will increase summer precipitation in northern China and push the boundary of the East Asian monsoon northward, ultimately resulting in increased precipitation in the monsoon fringe zone. Conclusions The influence of the tropical ocean on the dryness and humidity changes in the northeastern margin of the Qinghai-Xizang Plateau is relatively large at different time scales. In contrast, factors such as solar activity, Arctic sea ice, and plateau snow cover have different influences at different time scales. Recommendations and perspectives With the intensification of global climate change in the future, ocean activities are fraught with uncertainties. Although the drought in the middle and high latitudes of the northern hemisphere has alleviated, this is merely temporary. Once the PDO and AMO phases change, these areas will revert to drought. This will heighten the risk of regional ecological security. |
| Key words: northeastern margin of Qinghai-Xizang Plateau climate change modern scale millennium scale ocean activity |
