The North Atlantic Current is the major pathway for warm and saline water from the subtropics into the subpolar North Atlantic. Its main branch crosses 47°/48°N in the western North Atlantic basin and further north the Mid‐Atlantic Ridge (MAR) before entering the eastern subpolar basin where it partly feeds the subpolar gyre. To quantify the meridional exchange of water between the subtropical and subpolar regime in the interior eastern North Atlantic, long‐term (1993–2017) transport time series were calculated by combining data from inverted echo sounders taken in 2016–2017 with the dynamic topography from satellite altimetry. The data reveal an additional more direct pathway from the south across 47°/48°N with a mean northward transport of 9.1 Sv ± 0.8 Sv contributing about 22% to the total inflow of 41.4 Sv into the eastern subpolar basin. The transport time series of this pathway is significantly anticorrelated to the zonal transport across the MAR (R = −0.7), damping the interannual variability of the total transport into the subpolar eastern North Atlantic. Moreover, for the meridional transport in the interior eastern basin, a positive trend of 2.0 Sv ± 1.5 Sv per decade is found, partly balancing the negative decadal trend of −6.0 Sv ± 5.7 Sv observed in the interior western basin.

中文翻译：

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亚极东部北大西洋环流的趋势和运输变异性

北大西洋洋流是温水和咸水从亚热带进入亚极北大西洋的主要途径。它的主要分支在北大西洋盆地西部和北大西洋中脊（MAR）处相交47°/ 48°N，然后进入东部亚极盆地，部分向亚极回旋区供水。为了量化北大西洋内部东部亚热带和亚极地区之间的子午水交换，通过将2016-2017年倒置回波测深仪的数据与来自北大西洋的动态地形相结合，计算了长期（1993-2017）运输时间序列。卫星测高仪。数据显示，从南部跨越47°/ 48°N还有一条更直接的路径，平均向北输送9.1 Sv±0.8 Sv，占流入东部亚极盆地的41.4 Sv的总流入量的22％。R  = -0.7），从而减弱了向北极东部极地东部输电的总运输量的年际变化。此外，对于东部盆地内部的经向输运，发现每十年有2.0 Sv±1.5 Sv的正向趋势，部分平衡了内部盆地西部所观测到的-6.0 Sv±5.7 Sv的负年代际趋势。