A role for atmospheric CO2 in preindustrial climate forcing
A role for atmospheric CO2 in preindustrial climate forcing
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DOI：
10.1073/pnas.0807624105
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发表时间：
2008-10
期刊：
影响因子：
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通讯作者：
T. V. van Hoof;F. Wagner-Cremer;Wolfram M Kürschner;H. Visscher
中科院分区：
文献类型：
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作者：
T. V. van Hoof;F. Wagner-Cremer;Wolfram M Kürschner;H. Visscher
与南极冰芯的测量结果相互补充的是，对保存在泥炭和湖泊沉积物中的陆地植物叶片进行气孔频率分析，可以提供工业化前大气二氧化碳浓度的替代记录。基于荷兰的夏栎（英国橡树）叶片遗存得出的二氧化碳趋势，支持了在上个千年的前半叶存在显著的二氧化碳变异性这一观点。重建的几十年波动幅度高达体积百万分之34，大大超过了在南极冰芯中测量到的最大变化值。推断出的二氧化碳辐射强迫变化幅度与归因于其他机制（特别是太阳辐照度和火山活动）的变化幅度相似，因此可能会对政府间气候变化专门委员会的概念提出质疑，该委员会假定二氧化碳作为工业化前的气候强迫因素作用不大。基于气孔的二氧化碳趋势与北大西洋同期的海面温度趋势相关，这表明对于所记录的二氧化碳变化可能存在一种海洋源/汇机制。
Complementary to measurements in Antarctic ice cores, stomatal frequency analysis of leaves of land plants preserved in peat and lake deposits can provide a proxy record of preindustrial atmospheric CO2 concentration. CO2 trends based on leaf remains of Quercus robur (English oak) from the Netherlands support the presence of significant CO2 variability during the first half of the last millennium. The amplitude of the reconstructed multidecadal fluctuations, up to 34 parts per million by volume, considerably exceeds maximum shifts measured in Antarctic ice. Inferred changes in CO2 radiative forcing are of a magnitude similar to variations ascribed to other mechanisms, particularly solar irradiance and volcanic activity, and may therefore call into question the concept of the Intergovernmental Panel on Climate Change, which assumes an insignificant role of CO2 as a preindustrial climate-forcing factor. The stomata-based CO2 trends correlate with coeval sea-surface temperature trends in the North Atlantic Ocean, suggesting the possibility of an oceanic source/sink mechanism for the recorded CO2 changes.