Feedbacks in Emission-Driven and Concentration-Driven Global Carbon Budgets
Feedbacks in Emission-Driven and Concentration-Driven Global Carbon Budgets
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DOI：
10.1175/jcli-d-12-00365.1
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发表时间：
2013-05-01
影响因子：
4.9
通讯作者：
Arora, V. K.
中科院分区：
文献类型：
--
作者：
Boer, G. J.;Arora, V. K.
向大气中排放二氧化碳会影响陆地和海洋的碳收支，因为地球化学过程会对二氧化碳浓度的增加作出反应。生物地球化学过程还对温度和其他气候参数的变化做出反应。这种行为的特征在于碳浓度和碳气候反馈参数。本文的研究结果包括：1）将Boer和Arora的直接碳反馈理论扩展到辐射耦合模拟、化学耦合模拟和完全耦合模拟的结果; 2）简要分析了该理论与Friedlingstein等人的积分反馈理论之间的关系; 3)基于代表性浓度路径（RCP）RCP2.6、RCP4.5和RCP8.5的模拟的反馈分析; 4）指定大气CO2浓度或CO2排放的效果的比较;和5）两种反馈机制对大气CO2变化的累积贡献的相对重要性的量化。与早期的研究一致，碳浓度反馈对大气是负面的，碳气候反馈是正面的。然而，反馈行为的大小和演变取决于所采用的形式主义，所考虑的情景，以及来自排放或大气浓度的CO2的规格。这两个反馈参数可以相差两倍或两倍以上，这取决于情景和CO2排放量或浓度的规格。虽然反馈结果在质量上是有用的，并说明了碳预算行为，但它们在数量上适用于特定的情景和案例。
Emissions of CO2 into the atmosphere affect the carbon budgets of the land and ocean as biogeochemical processes react to increased CO2 concentrations. Biogeochemical processes also react to changes in temperature and other climate parameters. This behavior is characterized in terms of carbon-concentration and carbon-climate feedback parameters. The results of this study include 1) the extension of the direct carbon feedback formalism of Boer and Arora to include results from radiatively coupled simulations, as well as those from the biogeochemically coupled and fully coupled simulations used in earlier analyses; 2) a brief analysis of the relationship between this formalism and the integrated feedback formalism of Friedlingstein et al.; 3) the feedback analysis of simulations based on each of the representative concentration pathways (RCPs) RCP2.6, RCP4.5, and RCP8.5; 4) a comparison of the effects of specifying atmospheric CO2 concentrations or CO2 emissions; and 5) the quantification of the relative importance of the two feedback mechanisms in terms of their cumulative contribution to the change in atmospheric CO2.Feedback results are broadly in agreement with earlier studies in that carbon-concentration feedback is negative for the atmosphere and carbon-climate feedback is positive. However, the magnitude and evolution of feedback behavior depends on the formalism employed, the scenario considered, and the specification of CO2 from emissions or as atmospheric concentrations. Both feedback parameters can differ by factors of two or more, depending on the scenario and on the specification of CO2 emissions or concentrations. While feedback results are qualitatively useful and illustrative of carbon budget behavior, they apply quantitatively to particular scenarios and cases.