Volkov Denis L, Smith Ryan H, Garcia Rigoberto F, Smeed David A, Moat Ben I, Johns William E, Baringer Molly O
Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL, USA.
NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, USA.
Nat Commun. 2024 Sep 5;15(1):7780. doi: 10.1038/s41467-024-51879-5.
The potential weakening of the Atlantic Meridional Overturning Circulation (AMOC) in response to anthropogenic forcing, suggested by climate models, is at the forefront of scientific debate. A key AMOC component, the Florida Current (FC), has been measured using submarine cables between Florida and the Bahamas at 27°N nearly continuously since 1982. A decrease in the FC strength could be indicative of the AMOC weakening. Here, we reassess motion-induced voltages measured on a submarine cable and reevaluate the overall trend in the inferred FC transport. We find that the cable record beginning in 2000 requires a correction for the secular change in the geomagnetic field. This correction removes a spurious trend in the record, revealing that the FC has remained remarkably stable. The recomputed AMOC estimates at ~26.5°N result in a significantly weaker negative trend than that which is apparent in the AMOC time series obtained with the uncorrected FC transports.
气候模型显示,大西洋经向翻转环流(AMOC)可能因人为强迫而减弱,这一问题处于科学辩论的前沿。自1982年以来,AMOC的一个关键组成部分——佛罗里达洋流(FC),已通过佛罗里达和巴哈马群岛之间27°N处的海底电缆几乎连续进行了测量。FC强度的降低可能表明AMOC正在减弱。在此,我们重新评估了在海底电缆上测量的运动感应电压,并重新评估了推断的FC输运的总体趋势。我们发现,始于2000年的电缆记录需要对地磁场的长期变化进行校正。这种校正消除了记录中的虚假趋势,表明FC一直保持着显著的稳定。在约26.5°N处重新计算的AMOC估计值导致的负趋势明显弱于使用未校正的FC输运得到的AMOC时间序列中明显的负趋势。