A model-based constraint on CO2 fertilisation
A model-based constraint on CO2 fertilisation
复制标题
基于模型的二氧化碳施肥约束
DOI：
10.5194/bgd-9-9425-2012
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发表时间：
2020
影响因子：
11.4
通讯作者：
D. Gerten
中科院分区：
文献类型：
--
作者：
P. Holden;N. Edwards;D. Gerten
我们通过一个“自上而下”的方法，校准地球系统模型参数的大气CO2浓度的后工业化的增加所限制的陆地生物圈的CO2施肥的强度的约束。我们得出一个概率预测的全球平均强度的CO2施肥在自然界中，为1850年至2000年AD期间，隐含净的其他限制因素，如养分供应。该方法产生的估计是独立的CO2富集实验。为实现这一目标，一项基本要求是将土地使用变化方案纳入GENIE地球系统模型。利用瞬态GENIE模拟的671个成员的集合的输出，我们建立了一个模拟器的大气CO2浓度变化的变化，因为前工业化时期。我们使用这个模拟器对28维输入参数空间进行采样。模拟器输出的贝叶斯校准表明，响应于CO2从工业化前的值增加一倍，总初级生产力（GPP）的增加很可能（90%置信度）超过20%，最有可能的值为40- 60%。值得注意的是，我们并不代表所有可能的陆地汇的贡献机制。缺失的过程被归入我们的CO2施肥校准，因此代表了CO2施肥和其他缺失过程的综合影响。如果缺失的进程是一个净汇，那么我们的估计代表了一个上限。我们得出校准的估计与现有的估计是一致的碳通量。目前的陆-气通量（1990-2000年）估计为-0.7 GTC yr-1（可能的置信度为66%，范围为0.4至-1.7 GTC yr-1）。目前（1990-2000年）的海洋-大气通量估计为-2.3 GTC yr-1（可能在-1.8 GTC yr-1至-2.7 GTC yr-1之间）。我们估计，在后工业化时期（土地利用变化排放的二氧化碳施肥和气候汇净）累计净土地排放量为66 GTC，可能在0至128 GTC的范围内。
We derive a constraint on the strength of CO 2 fertilisation of the terrestrial biosphere through a “top-down” approach, calibrating Earth system model parameters constrained by the post-industrial increase of atmospheric CO 2 concentration. We derive a probabilistic prediction for the globally averaged strength of CO 2 fertilisation in nature, for the period 1850 to 2000 AD, implicitly net of other limiting factors such as nutrient availability. The approach yields an estimate that is independent of CO 2 enrichment experiments. To achieve this, an essential requirement was the incorporation of a land use change (LUC) scheme into the GENIE Earth system model. Using output from a 671-member ensemble of transient GENIE simulations, we build an emulator of the change in atmospheric CO 2 concentration change since the preindustrial period. We use this emulator to sample the 28-dimensional input parameter space. A Bayesian calibration of the emulator output suggests that the increase in gross primary productivity (GPP) in response to a doubling of CO2 from preindustrial values is very likely (90 % confidence) to exceed 20 %, with a most likely value of 40– 60 %. It is important to note that we do not represent all of the possible contributing mechanisms to the terrestrial sink. The missing processes are subsumed into our calibration of CO2 fertilisation, which therefore represents the combined effect of CO2 fertilisation and additional missing processes. If the missing processes are a net sink then our estimate represents an upper bound. We derive calibrated estimates of carbon fluxes that are consistent with existing estimates. The present-day land–atmosphere flux (1990–2000) is estimated at −0.7 GTC yr−1 (likely, 66 % confidence, in the range 0.4 to −1.7 GTC yr−1). The present-day ocean–atmosphere flux (1990–2000) is estimated to be −2.3 GTC yr−1 (likely in the range−1.8 to−2.7 GTC yr−1). We estimate cumulative net land emissions over the post-industrial period (land use change emissions net of the CO 2 fertilisation and climate sinks) to be 66 GTC, likely to lie in the range 0 to 128 GTC.
影响因子：
4.6
作者：
P. Holden;N. Edwards;K. Oliver;T. Lenton;R. Wilkinson
通讯作者：
P. Holden;N. Edwards;K. Oliver;T. Lenton;R. Wilkinson