Persistent Discrepancies between Observed and Modeled Trends in the Tropical Pacific Ocean
Persistent Discrepancies between Observed and Modeled Trends in the Tropical Pacific Ocean
复制标题
热带太平洋观测到的趋势与模拟的趋势之间持续存在差异
DOI：
10.1175/jcli-d-21-0648.1
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发表时间：
2022
影响因子：
4.9
通讯作者：
Cane, Mark
中科院分区：
文献类型：
--
作者：
Seager, Richard;Henderson, Naomi;Cane, Mark
近几十年来热带太平洋海面和上层海洋温度的趋势在基于观测的产品，海洋再分析和耦合模式相互比较项目第六阶段和多模式大型集合档案的最新模型中进行了研究。比较使用三个指标的海表温度（SST）的趋势-东西和南北SST梯度和模式相关的赤道地区，以及温跃层深度的变化。结果表明，最新一代的模式坚持不再现的观测为基础的SST趋势作为辐射强迫的响应，后者是在远边缘或超出模拟的内部变率的范围。在赤道冷舌上涌区观察到的温跃层变浅和缺乏变暖的组合同样处于模拟行为的极端极限。在过去的世纪半中，观测到的东西向SST梯度增强的趋势以及在五个观测网格数据集中的四个中赤道南北向SST梯度增强的趋势的持续性也达到了模式行为的极限。得出的结论是，观察到的趋势极不可能与建模的内部变异性一致。相反，结果支持的论点，观察到的趋势是一个辐射强迫的反应，其中增强的东西SST梯度和温跃层变浅是关键，最新一代的气候模式仍然无法模拟这方面的气候变化。
The trends over recent decades in tropical Pacific sea surface and upper ocean temperature are examined in observations-based products, an ocean reanalysis and the latest models from the Coupled Model Intercomparison Project phase six and the Multimodel Large Ensembles Archive. Comparison is made using three metrics of sea surface temperature (SST) trend—the east–west and north–south SST gradients and a pattern correlation for the equatorial region—as well as change in thermocline depth. It is shown that the latest generation of models persist in not reproducing the observations-based SST trends as a response to radiative forcing and that the latter are at the far edge or beyond the range of modeled internal variability. The observed combination of thermocline shoaling and lack of warming in the equatorial cold tongue upwelling region is similarly at the extreme limit of modeled behavior. The persistence over the last century and a half of the observed trend toward an enhanced east–west SST gradient and, in four of five observed gridded datasets, to an enhanced equatorial north–south SST gradient, is also at the limit of model behavior. It is concluded that it is extremely unlikely that the observed trends are consistent with modeled internal variability. Instead, the results support the argument that the observed trends are a response to radiative forcing in which an enhanced east–west SST gradient and thermocline shoaling are key and that the latest generation of climate models continue to be unable to simulate this aspect of climate change.