论文标题
CMIP6 GCM合奏成员与全球表面温度
CMIP6 GCM ensemble members versus global surface temperatures
论文作者
论文摘要
耦合模型比较项目（第6阶段）（CMIP6）全局循环模型（GCMS）预测平衡气候灵敏度（ECS）值在1.8至5.7 $^\ circe $ c之间。为了缩小该范围，我们将38 GCMS组分为低，中和高EC子组，并测试其在后期观察到的平均全球表面变暖的准确性和精度，从1980- 1990年到2011 - 2021年，ERE5 T2M，HADCRUT5，GOISTEMP V4，GISTEMP V4和NOAAGLOBTEMP V5全球表面温度温度记录。我们还将GCM后广播与基于卫星的UAH MSU V6较低对流层全球温度记录进行了比较。我们在四个略有不同的强迫条件下，688 GCM成员模拟以及在三个不同模型精度要求下的内部变异性的蒙特卡洛建模，在四个略有不同的强迫条件下，使用143个GCM集合平均模拟。我们发现，培养基和高ECS GCM的运行太热，分别为95％和97％的病例。低ECS GCM组与从表面温度记录获得的变暖值最吻合，范围在0.52至0.58 $^\ Circ $ c之间。但是，当比较在陆地和海洋区域上观察到的GCM后期变暖时，基于表面的温度记录似乎表现出明显的变暖偏见。如果基于卫星的UAH MSU LT记录是准确的，那么从1980年到2021年的实际表面变暖可能约为0.40 $^\ Circ $ C（或更少），即比基于表面的温度记录所报告的较低约30％。后一种情况意味着，即使是低ECS模型也会从1980年到2021年产生过度的变暖。这些结果表明，实际EC可能相对较低，即低于3 $^\ Circ $ c，甚至小于2 $^\ circc $ c。因此，在接下来的几十年中，预计的全球气候变暖可能是中等的，可能并不特别令人震惊。
The Coupled Model Intercomparison Project (phase 6) (CMIP6) global circulation models (GCMs) predict equilibrium climate sensitivity (ECS) values ranging between 1.8 and 5.7 $^\circ$C. To narrow this range, we group 38 GCMs into low, medium and high ECS subgroups and test their accuracy and precision in hindcasting the mean global surface warming observed from 1980-1990 to 2011-2021 in the ERA5 T2m, HadCRUT5, GISTEMP v4, and NOAAGlobTemp v5 global surface temperature records. We also compare the GCM hindcasts to the satellite-based UAH MSU v6 lower troposphere global temperature record. We use 143 GCM ensemble averaged simulations under four slightly different forcing conditions, 688 GCM member simulations, and Monte Carlo modeling of the internal variability of the GCMs under three different model accuracy requirements. We found that the medium and high ECS GCMs run too hot up to over 95% and 97% of cases, respectively. The low ECS GCM group agrees best with the warming values obtained from the surface temperature records, ranging between 0.52 and 0.58 $^\circ$C. However, when comparing the observed and GCM hindcasted warming on land and ocean regions, the surface-based temperature records appear to exhibit a significant warming bias. If the satellite based UAH MSU lt record is accurate, actual surface warming from 1980 to 2021 may have been around 0.40 $^\circ$C (or less), i.e. up to about 30% less than what is reported by the surface based temperature records. The latter situation implies that even the low ECS models would have produced excessive warming from 1980 to 2021. These results suggest that the actual ECS may be relatively low, i.e. lower than 3 $^\circ$C or even less than 2 $^\circ$C. Therefore, the projected global climate warming over the next few decades could be moderate and probably not particularly alarming.
