Hu Shijian, Sprintall Janet, Guan Cong, McPhaden Michael J, Wang Fan, Hu Dunxin, Cai Wenju
CAS Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China.
Sci Adv. 2020 Feb 5;6(6):eaax7727. doi: 10.1126/sciadv.aax7727. eCollection 2020 Feb.
Ocean circulation redistributes Earth's energy and water masses and influences global climate. Under historical greenhouse warming, regional ocean currents show diverse tendencies, but whether there is an emerging trend of the global mean ocean circulation system is not yet clear. Here, we show a statistically significant increasing trend in the globally integrated oceanic kinetic energy since the early 1990s, indicating a substantial acceleration of global mean ocean circulation. The increasing trend in kinetic energy is particularly prominent in the global tropical oceans, reaching depths of thousands of meters. The deep-reaching acceleration of the ocean circulation is mainly induced by a planetary intensification of surface winds since the early 1990s. Although possibly influenced by wind changes associated with the onset of a negative Pacific decadal oscillation since the late 1990s, the recent acceleration is far larger than that associated with natural variability, suggesting that it is principally part of a long-term trend.
海洋环流重新分配地球的能量和水体，并影响全球气候。在历史温室变暖情况下，区域洋流呈现出不同的趋势，但全球平均海洋环流系统是否存在新出现的趋势尚不清楚。在此，我们表明自20世纪90年代初以来，全球综合海洋动能存在统计学上显著的上升趋势，这表明全球平均海洋环流有大幅加速。动能的增加趋势在全球热带海洋尤为突出，可达数千米深度。自20世纪90年代初以来，海洋环流的深度加速主要是由地表风的行星尺度增强引起的。尽管可能受到自20世纪90年代末以来与太平洋年代际振荡转为负相位相关的风变化的影响，但近期的加速远大于与自然变率相关的加速，这表明它主要是长期趋势的一部分。
