High regional climate sensitivity over continental China constrained by glacial-recent changes in temperature and the hydrological cycle
High regional climate sensitivity over continental China constrained by glacial-recent changes in temperature and the hydrological cycle
复制标题
DOI：
10.1073/pnas.1213366110
复制
发表时间：
2013-05
期刊：
影响因子：
--
通讯作者：
R. Eagle;C. Risi;Jonathan L. Mitchell;J. Eiler;U. Seibt;J. Neelin;Gaojun Li;A. Tripati
中科院分区：
文献类型：
--
作者：
R. Eagle;C. Risi;Jonathan L. Mitchell;J. Eiler;U. Seibt;J. Neelin;Gaojun Li;A. Tripati
东亚季风是地球上最重要的气候现象之一，大量的古气候档案显示出它在轨道和亚轨道时间尺度上的变化。对与这些过去变化相关的气候变化的数量限制是有限的，但需要限制该区域对温室气体水平变化的敏感性。这里，我们展示了中国中部是一个自上一次冰盛期以来经历了比气候模型通常模拟的更大的温度变化的地区。对中国黄土高原中部碳酸盐岩进行了块状同位素测温，重建了末次冰盛期至今的温度和水同位素漂移。我们发现夏季温度变化为6-7°C，这与这里提供的气候模式模拟的结果相同。代理数据揭示了冰河时代大气水向较轻同位素组成转变的证据，这也被我们的模型所捕获。对模式输出的分析表明，由于驻波的影响，大陆中国上空的冰川冷却显著放大，而驻波又被大陆冰盖加强。这些结果不仅支持中国中部的高区域气候敏感性，而且突出了行星尺度大气动力学在区域气候对大陆冰川、温室气体水平变化和日照的敏感性中的基础作用。
The East Asian monsoon is one of Earth’s most significant climatic phenomena, and numerous paleoclimate archives have revealed that it exhibits variations on orbital and suborbital time scales. Quantitative constraints on the climate changes associated with these past variations are limited, yet are needed to constrain sensitivity of the region to changes in greenhouse gas levels. Here, we show central China is a region that experienced a much larger temperature change since the Last Glacial Maximum than typically simulated by climate models. We applied clumped isotope thermometry to carbonates from the central Chinese Loess Plateau to reconstruct temperature and water isotope shifts from the Last Glacial Maximum to present. We find a summertime temperature change of 6–7 °C that is reproduced by climate model simulations presented here. Proxy data reveal evidence for a shift to lighter isotopic composition of meteoric waters in glacial times, which is also captured by our model. Analysis of model outputs suggests that glacial cooling over continental China is significantly amplified by the influence of stationary waves, which, in turn, are enhanced by continental ice sheets. These results not only support high regional climate sensitivity in Central China but highlight the fundamental role of planetary-scale atmospheric dynamics in the sensitivity of regional climates to continental glaciation, changing greenhouse gas levels, and insolation.