The Labrador Sea is known for strong surface heat losses and deep ocean ventilation in the wintertime as well as high biological productivity and carbon export associated with extensive spring blooms. Using satellite-derived estimates of chlorophyll-a and net primary productivity, this study documents that the Labrador Sea has recently become more productive, evident in the form of more intense and spatially extensive phytoplankton blooms. The spatial and temporal variability in chlorophyll-a was compared against trends in nutrient concentrations across the Labrador Sea. Nutrient concentrations were obtained on a repeat hydrography line running from the Labrador to Greenland shelves. The 25-year long time series of nitrate, phosphate and silicate concentrations along the AR7 W line reveal decadal trends in the upper Labrador Sea. A comparison of these nutrients with basin-averaged annual mean surface chlorophyll-a concentrations reveals positive correlations in the upper 1000 m of the Labrador Sea. Furthermore, nutrient concentrations in the upper 1000 m were strongly correlated with wintertime convection depth. During years of strong winter convection, more nutrients are entrained from the deeper Labrador Sea, which then can be distributed through the Western Greenland and Irminger Currents and eddy activity, allowing sustained phytoplankton growth further north in the Labrador Sea.

拉布拉多海以冬季强烈的地表热损失和深海通风以及与春季广泛开花相关的高生物生产力和碳输出而闻名。使用卫星衍生的叶绿素-a 和净初级生产力估计，这项研究记录了拉布拉多海最近变得更有生产力，以更强烈和空间广泛的浮游植物水华的形式明显。将叶绿素-a 的空间和时间变异性与拉布拉多海的养分浓度趋势进行了比较。在从拉布拉多到格陵兰大陆架的重复水文测量线上获得了营养浓度。沿 AR7 W 线长达 25 年的硝酸盐、磷酸盐和硅酸盐浓度的时间序列揭示了上拉布拉多海的年代际趋势。这些营养物质与流域平均年平均表面叶绿素-a 浓度的比较揭示了拉布拉多海上部 1000 米的正相关。此外，上部 1000 米的养分浓度与冬季对流深度密切相关。在多年的强烈冬季对流中，更多的营养物质从拉布拉多海深处被带走，然后可以通过格陵兰岛西部和伊明格洋流和涡流活动进行分配，从而使拉布拉多海更北部的浮游植物持续生长。