The latitudinal temperature gradient and its climate dependence as inferred from foraminiferal δ(18)O over the past 95 million years.
The latitudinal temperature gradient and its climate dependence as inferred from foraminiferal δ(18)O over the past 95 million years.
复制标题
DOI：
10.1073/pnas.2111332119
复制
发表时间：
2022-03-15
影响因子：
11.1
通讯作者：
Hull PM
中科院分区：
文献类型：
--
作者：
Gaskell DE;Huber M;O'Brien CL;Inglis GN;Acosta RP;Poulsen CJ;Hull PM
低纬度和高纬度之间的温差是衡量全球气候系统重新分配热量的效率的一个指标，用于测试模型在时间上代表气候系统的能力。在这里，我们表明，纬度温度梯度表现出一致的逆关系，全球平均海面温度至少在过去的9500万年。我们的研究结果有助于减少气候模型和温度的经验估计之间的冲突，并主张在不同背景状态下热传输和辐射传输动力学的基本一致性。纬度温度梯度是气候系统的一个基本状态参数，与热输送和辐射传输的动力学有关。因此，它是温度替代重建和全球气候模型的主要目标。然而，重建纬度温度梯度在过去的气候仍然具有挑战性，由于缺乏适当的代理记录和大代理模式的分歧。在这里，我们开发了利用广泛汇编的南极有孔虫δ 18 O来重建过去9500万年（My）的纬度海面温度（SST）梯度的连续记录的方法。我们发现，纬度SST梯度范围为26.5至15.3 °C，平均全球SST范围为15.3至32.5 °C，在最冷的时间间隔内梯度最高。根据这一关系，我们计算出极放大因子（PAF;>60° S SST变化与全球平均SST变化的比值）为1.44 ± 0.15。我们的结果比以前基于代理的估计更接近模型预测，主要是因为基于δ 18 O的高纬度SST估计更接近海底温度，产生更高的梯度。低纬度和高纬度浮游有孔虫和底栖有孔虫的δ 18 O值在许多气候状态下的一致协方差表明，气候系统的多个方面存在根本性的约束，将深海温度，纬度SST梯度和全球平均SST与大气CO2，大陆配置，海洋门户和大陆冰盖范围的巨大变化联系起来。这意味着在截然不同的背景状态下，气候系统具有重要的内在驱动的可预测性。
The temperature difference between low and high latitudes is one measure of the efficiency of the global climate system in redistributing heat and is used to test the ability of models to represent the climate system through time. Here, we show that the latitudinal temperature gradient has exhibited a consistent inverse relationship with global mean sea-surface temperature for at least the past 95 million years. Our results help reduce conflicts between climate models and empirical estimates of temperature and argue for a fundamental consistency in the dynamics of heat transport and radiative transfer across vastly different background states. The latitudinal temperature gradient is a fundamental state parameter of the climate system tied to the dynamics of heat transport and radiative transfer. Thus, it is a primary target for temperature proxy reconstructions and global climate models. However, reconstructing the latitudinal temperature gradient in past climates remains challenging due to the scarcity of appropriate proxy records and large proxy–model disagreements. Here, we develop methods leveraging an extensive compilation of planktonic foraminifera δ18O to reconstruct a continuous record of the latitudinal sea-surface temperature (SST) gradient over the last 95 million years (My). We find that latitudinal SST gradients ranged from 26.5 to 15.3 °C over a mean global SST range of 15.3 to 32.5 °C, with the highest gradients during the coldest intervals of time. From this relationship, we calculate a polar amplification factor (PAF; the ratio of change in >60° S SST to change in global mean SST) of 1.44 ± 0.15. Our results are closer to model predictions than previous proxy-based estimates, primarily because δ18O-based high-latitude SST estimates more closely track benthic temperatures, yielding higher gradients. The consistent covariance of δ18O values in low- and high-latitude planktonic foraminifera and in benthic foraminifera, across numerous climate states, suggests a fundamental constraint on multiple aspects of the climate system, linking deep-sea temperatures, the latitudinal SST gradient, and global mean SSTs across large changes in atmospheric CO2, continental configuration, oceanic gateways, and the extent of continental ice sheets. This implies an important underlying, internally driven predictability of the climate system in vastly different background states.
登录
查看更多内容
影响因子：
64.8
作者：
Cramwinckel, Margot J.;Huber, Matthew;Sluijs, Appy
通讯作者：
Sluijs, Appy
影响因子：
6.8
作者：
Brady, E.;Stevenson, S.;Zhu, J.
通讯作者：
Zhu, J.
DOI：
10.1073/pnas.1321441111
发表时间：
2014-05-06
影响因子：
11.1
作者：
Douglas, Peter M. J.;Affek, Hagit P.;Pagani, Mark
通讯作者：
Pagani, Mark
影响因子：
5.3
作者：
Damste, Jaap S. Sinninghe;van Bentum, Elisabeth C.;Schouten, Stefan
通讯作者：
Schouten, Stefan
影响因子：
16.6
作者：
Donnadieu Y;Pucéat E;Moiroud M;Guillocheau F;Deconinck JF
通讯作者：
Deconinck JF