The transient climate response to cumulative carbon emissions (TCRE) is a key metric in estimating the remaining carbon budget for given temperature targets. However, the TCRE has a small scenario dependence that can be non-negligible for stringent temperature targets. To investigate the parametric correlations and scenario dependence of the TCRE, the present study uses a 512-member ensemble of an Earth system model of intermediate complexity (EMIC) perturbing 11 physical and biogeochemical parameters under scenarios with steady increases of 0.25%, 0.5%, 1%, 2%, or 4% per annum (ppa) in the atmospheric CO₂ concentration (pCO₂), or an initial increase of 1% followed by an annual decrease of 1% thereafter. Although a small difference of 5% (on average) in the TCRE is observed between the 1-ppa and 0.5-ppa scenarios, a significant scenario dependence is found for the other scenarios, with a tendency toward large values in gradual or decline-after-a-peak scenarios and small values in rapidly increasing scenarios. For all scenarios, correlation analysis indicates a remarkably large correlation between the equilibrium climate sensitivity (ECS) and the relative change in the TCRE, which is attributed to the longer response time of the high ECS model. However, the correlations of the ECS with the TCRE and its scenario dependence for scenarios with large pCO₂ increase rates are slightly smaller, and those of biogeochemical parameters such as plant respiration and the overall pCO₂–carbon cycle feedback are larger, than in scenarios with gradual increases. The ratio of the TCREs under the overshooting (i.e., 1-ppa decrease after a 1-ppa increase) and 1-ppa increase only scenarios had a clear positive relation with zero-emission commitments. Considering the scenario dependence of the TCRE, the remaining carbon budget for the 1.5 °C target could be reduced by 17 or 22% (before and after considering the unrepresented Earth system feedback) for the most extreme case (i.e., the 67^th percentile when using the 0.25-ppa scenario as compared to the 1-ppa increase scenario). A single ensemble EMIC is also used to indicate that, at least for high ECS (high percentile) cases, the scenario dependence of the TCRE should be considered when estimating the remaining carbon budget.

对累积碳排放量的短暂气候响应（TCRE）是估算给定温度目标下剩余碳预算的关键指标。但是，TCRE对场景的依赖性很小，对于严格的温度目标而言，这可以忽略不计。为了研究TCRE的参数相关性和情景相关性，本研究使用512个成员的中度复杂度（EMIC）地球系统模型，在情景中稳定增长0.25％，0.5％，大气中CO ₂浓度（pCO ₂每年1％，2％或4％（ppa）），或最初增加1％，然后每年减少1％。尽管在1-ppa和0.5-ppa方案之间观察到TCRE的平均差异很小（平均为5％），但在其他方案中发现了显着的方案依赖性，并且有逐渐增加或逐步下降的趋势。高峰情景和快速增长的情景中的小价值。对于所有场景，相关性分析都表明，平衡气候敏感性（ECS）与TCRE的相对变化之间存在非常大的相关性，这归因于高ECS模型的响应时间更长。但是，对于pCO ₂大的场景，ECS与TCRE的相关性及其场景依赖性与逐渐增加的情况相比，增加速度要小一些，而生物地球化学参数（例如植物呼吸作用和总体pCO _2-碳循环反馈）的增加幅度更大。在超调（即在增加1-ppa之后减少1-ppa）和仅增加1-ppa情况下的TCRE比率与零排放承诺有着明显的正相关关系。考虑到TCRE的情景依赖性，在最极端的情况下（即第67^位），可以将1.5°C目标的剩余碳预算减少17或22％（在考虑无代表性的地球系统反馈之前和之后）。使用0.25-ppa方案与增加1-ppa方案的百分比）。单个集成EMIC还用于指示，至少对于高ECS（高百分位数）情况，在估算剩余碳预算时应考虑TCRE的情景依赖性。