A probabilistic calibration of climate sensitivity and terrestrial carbon change in GENIE-1
A probabilistic calibration of climate sensitivity and terrestrial carbon change in GENIE-1
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DOI：
10.1007/s00382-009-0630-8
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发表时间：
2010-10
期刊：
影响因子：
4.6
通讯作者：
P. Holden;N. Edwards;K. Oliver;T. Lenton;R. Wilkinson
中科院分区：
文献类型：
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作者：
P. Holden;N. Edwards;K. Oliver;T. Lenton;R. Wilkinson
为了研究末次盛冰期和未来的气候，我们“预校准”的中间复杂性模型GENIE-1的模型的确定性仿真应用拒绝抽样方法。我们开发了约1,000个参数集，这些参数集再现了现代气候的主要特征，但不是精确的观测。这使得大范围的大规模反馈响应强度，其中一般包括范围内的GCM行为。我们建立了一个气候敏感性的确定性模拟器，并量化了大气（±0.93°C，1σ）植被（±0.32°C），海洋（±0.24°C）和海冰（±0.14°C）参数化对总不确定性的贡献。然后，我们进行LGM约束贝叶斯校准，结合数据驱动的先验知识，并正式解释结构性错误。我们估计气候敏感性可能（66%置信度）在2.6-4.4°C范围内，峰值概率在3.6°C。我们估计LGM冷却可能在5.3-7.5°C之间，峰值可能在6.2°C。除了全球温度变化的估计，我们运用我们的合奏来获得LGM和2xCO 2概率分布的陆地碳储量，大西洋翻转和海冰覆盖。值得注意的是，在2xCO 2下，我们计算出平衡陆地碳储量从现代值减少的概率为37%，因此陆地汇已成为大气CO2的净来源。
In order to investigate Last Glacial Maximum and future climate, we “precalibrate” the intermediate complexity model GENIE-1 by applying a rejection sampling approach to deterministic emulations of the model. We develop ~1,000 parameter sets which reproduce the main features of modern climate, but not precise observations. This allows a wide range of large-scale feedback response strengths which generally encompass the range of GCM behaviour. We build a deterministic emulator of climate sensitivity and quantify the contributions of atmospheric (±0.93°C, 1σ) vegetation (±0.32°C), ocean (±0.24°C) and sea–ice (±0.14°C) parameterisations to the total uncertainty. We then perform an LGM-constrained Bayesian calibration, incorporating data-driven priors and formally accounting for structural error. We estimate climate sensitivity aslikely(66% confidence) to lie in the range 2.6–4.4°C, with a peak probability at 3.6°C. We estimate LGM cooling likely to lie in the range 5.3–7.5°C, with a peak probability at 6.2°C. In addition to estimates of global temperature change, we apply our ensembles to derive LGM and 2xCO2probability distributions for land carbon storage, Atlantic overturning and sea–ice coverage. Notably, under 2xCO2we calculate a probability of 37% that equilibrium terrestrial carbon storage is reduced from modern values, so the land sink has become a net source of atmospheric CO2.