Continuous measurements from the OSNAP (Overturning in the Subpolar North Atlantic Program) array yield the first estimates of trans-basin heat and salinity transports in the subpolar latitudes. For the period from August 2014 to May 2018, there is a poleward heat transport of 0.50 ± 0.05 PW and a poleward salinity transport of 12.5 ± 1.0 Sv across the OSNAP section. Based on the mass and salt budget analyses, we estimate that a surface freshwater input of 0.36 ± 0.05 Sv over the broad subpolar-Arctic region is needed to balance the ocean salinity change created by the OSNAP transports. The overturning circulation is largely responsible for setting these heat and salinity transports (and the derived surface freshwater input) derived from the OSNAP array, while the gyre (isopycnal) circulation contributes to a lesser, but still significant, extent. Despite its relatively weak overturning and heat transport, the Labrador Sea is a strong contributor to salinity and freshwater changes in the subpolar region. Combined with trans-basin transport estimates at other locations, we provide new estimates for the time-mean surface heat and freshwater divergences over a wide domain of the Arctic-North Atlantic region to the north and south of the OSNAP line. Furthermore, we estimate the total heat and freshwater exchanges across the surface area of the extratropical North Atlantic between the OSNAP and the RAPID-MOCHA (RAPID Meridional Overturning Circulation and Heat-flux Array) arrays, by combining the cross-sectional transports with vertically-integrated ocean heat and salinity content. Comparisons with the air-sea heat and freshwater fluxes from atmospheric reanalysis products show an overall consistency, yet with notable differences in the magnitudes during the observation time period.

来自 OSNAP（次极北大西洋倾覆计划）阵列的连续测量产生了对次极纬度跨盆地热量和盐度传输的首次估计。2014 年 8 月至 2018 年 5 月期间，整个 OSNAP 部分有 0.50 ± 0.05 PW 的向极热传输和 12.5 ± 1.0 Sv 的极向盐度传输。根据质量和盐分收支分析，我们估计需要 0.36 ± 0.05 Sv 的地表淡水输入在广阔的亚极地-北极地区，以平衡 OSNAP 传输造成的海洋盐度变化。翻转环流主要负责设置来自 OSNAP 阵列的这些热量和盐度传输（以及衍生的地表淡水输入），而环流（等密度）环流的贡献程度较小，但仍然很重要。尽管倾覆和热量传输相对较弱，但拉布拉多海是次极地地区盐度和淡水变化的重要因素。结合其他地点的跨流域传输估算，我们提供了对北极-北大西洋地区到 OSNAP 线以北和以南的广阔区域的时间平均地表热量和淡水差异的新估算。此外，我们通过将横截面传输与垂直方向相结合，估计了 OSNAP 和 RAPID-MOCHA（快速经向翻转环流和热通量阵列）阵列之间跨温带北大西洋表面区域的总热量和淡水交换。综合海洋热量和盐度含量。