Moored Observations of Transport in the Solomon Sea Journal of Geophysical Research: Oceans

The Solomon Sea is a marginal sea in the western Pacific warm pool that contains the South Pacific low latitude western boundary currents. These low latitude western boundary currents chiefly exit the Solomon Sea through three channels (Vitiaz Strait, St. George's Channel, and Solomon Strait) and serve as the primary source water for the Equatorial Undercurrent. Simulations have shown that transport partitioning between the straits determines the water mass structure of the Equatorial Undercurrent, but the relative contributions of transport through each strait have not been observed before. As part of the Southwest Pacific Ocean Circulation and Climate Experiment, an array of moorings was deployed simultaneously in the three outflow channels of the Solomon Sea from July 2012 until March 2014 to resolve transport and water properties in each strait. Above deep isopycnals (σ0 ≤ 27.5), Vitiaz and Solomon Straits account for 54.2% and 36.2% of the mean transport, respectively, with the remaining 9.6% exiting through St. George's Channel. The strongest subinertial transport variability is observed in Solomon Strait and dominates total Solomon Sea transport variability, and a significant fraction of this variability is at intraseasonal time scales. Finally, a previously unobserved deep current at 1,500‐m depth is found to enter the Solomon Sea through Solomon Strait, with a deployment‐mean transport of 4.6 Sv (Sv ≡106 m3/s).

所罗门海是西太平洋暖池中的一处边缘海，域内发育南太平洋低纬度西边界流。该低纬度西边界流主要通过三条海峡（维蒂亚兹海峡、圣乔治海峡与所罗门海峡）流出所罗门海，同时也是赤道潜流（Equatorial Undercurrent）的主要水源。数值模拟结果表明，各海峡间的输运分配决定了赤道潜流的水团结构，但此前尚未有观测获取通过各海峡的输运相对贡献。作为西南太平洋海洋环流与气候试验的组成部分，研究团队于2012年7月至2014年3月期间，在所罗门海的三条外流海峡同步部署了锚系阵列，以解析各海峡内的输运过程与水团属性。在深层等密度面（σ0 ≤ 27.5）以上的水层中，维蒂亚兹海峡与所罗门海峡的平均输运占比分别为54.2%与36.2%，剩余9.6%的输运经圣乔治海峡流出。观测到所罗门海峡的亚惯性输运变率最强，其主导了所罗门海整体的输运变率，且该变率中有显著部分发生在季节内时间尺度上。最后，研究团队发现了一条此前未被观测到的1500米深层海流，该海流经所罗门海峡流入所罗门海，其部署期间的平均输运量为4.6斯维尔德鲁普（Sv ≡ 10^6 m³/s）。