通过对过去5.4亿年气候模拟的综合分析，该课题组研究人员发现热带辐合带的迁移主要是由大陆构型通过两种相互竞争的途径控制的：半球辐射不对称和跨赤道海洋热传输。吸收太阳辐射的半球不对称性主要是由陆地-海洋反照率的对比产生的，这种不对称性只能通过陆地的分布来预测。跨赤道海洋热输送与表面风应力的半球不对称性密切相关，而半球风应力又受海洋表面积的半球不对称性控制。这些结果使课题组能够通过主要取决于陆地纬度分布的简单机制来理解大陆演化对全球海洋-大气环流的影响。
据介绍，热带辐合带(ITCZ)位置的变化对天气、气候和社会具有重要意义。在当前和未来变暖的气候条件下，热带辐合带的变化已经得到了广泛的研究;然而，人们对它在过去的地质时间尺度上的迁移知之甚少。
附：英文原文
Title: Continental drift shifts tropical rainfall by altering radiation and ocean heat transport
Author: Jing Han, Ji Nie, Yongyun Hu, William R. Boos, Yonggang Liu, Jun Yang, Shuai Yuan, Xiang Li, Jiaqi Guo, Jiawenjing Lan, Qifan Lin, Xiujuan Bao, Mengyu Wei, Zhibo Li, Kai Man, Zihan Yin
Issue&Volume: 2023-03-08
Abstract: Shifts in the position of the intertropical convergence zone (ITCZ) have great importance for weather, climate, and society. The ITCZ shifts have been extensively studied in current and future warmer climate; however, little is known for its migration in the past on geological time scales. Using an ensemble of climate simulations over the past 540 million years, we show that ITCZ migrations are controlled primarily by continental configuration through two competing pathways: hemispheric radiation asymmetry and cross-equatorial ocean heat transport. The hemispheric asymmetry of absorbed solar radiation is produced mainly by land-ocean albedo contrast, which can be predicted using only the landmass distribution. The cross-equatorial ocean heat transport is strongly associated with the hemispheric asymmetry of surface wind stress, which is, in turn, controlled by the hemispheric asymmetry of ocean surface area. These results allow the influence of continental evolution on global ocean-atmosphere circulations to be understood through simple mechanisms that depend primarily on the latitudinal distribution of land.
DOI: adf7209
Source: https://www.science.org/doi/10.1126/sciadv.adf7209