Global Evaluation of Proxy System Models for Stable Water Isotopes With Realistic Atmospheric Forcing
Global Evaluation of Proxy System Models for Stable Water Isotopes With Realistic Atmospheric Forcing
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DOI：
10.1029/2018jd029463
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发表时间：
2019-08
期刊：
影响因子：
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通讯作者：
A. Okazaki;K. Yoshimura
中科院分区：
文献类型：
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作者：
A. Okazaki;K. Yoshimura
代用系统模式（PSM）是气候模拟和仪器观测之前的气候记录之间的重要桥梁。PSM有助于解释代理显示的内容以及它们如何记录气候。虽然以前的研究已经评估了个别网站的PSM，他们在全球范围内的系统评价尚未进行。这项研究评估了1950-2007年期间PSM在冰芯，珊瑚和树环纤维素中稳定水同位素的性能。所有代理类型的平均状态的空间分布都得到了很好的模拟，尽管树轮纤维素存在偏差。年际变化很好地模拟了珊瑚和树轮纤维素。这些结果表明，模型代表的代理的关键机制。相反，冰芯年际变化的再现性明显低于其他代理。虽然再现性是有限的大气强迫用于驱动模型，结果表明，PSM可能会错过沉积后的过程，如升华冰芯的年际时间尺度。
Proxy system models (PSMs) are an important bridge between climate simulations and climate records prior to the period where instrumental observations are available. PSMs help to interpret what proxies show and how they record climate. Although previous studies have evaluated PSMs for individual sites, their systematic evaluation on a global scale has not yet been conducted. This study evaluated the performance of PSMs for stable water isotopes in ice cores, corals, and tree‐ring cellulose for the period 1950–2007. Spatial distributions of the mean state were well simulated for all proxy types, albeit with a bias for tree‐ring cellulose. Interannual variability was well simulated for corals and tree‐ring cellulose. These results indicate that the models represent key mechanisms for the proxies. In contrast, the reproducibility of interannual variability in ice cores was markedly lower than that for the other proxies. Although the reproducibility was limited by the atmospheric forcing used to drive the model, the results suggest that the PSM may be missing postdepositional processes, such as sublimation for ice cores on the interannual time scale.