Salinity Variations in the Southern California Current
Salinity Variations in the Southern California Current
复制标题
南加州洋流的盐度变化
DOI：
10.1175/jpo2759.1
复制
发表时间：
2005
影响因子：
3.5
通讯作者：
P. Niiler
中科院分区：
文献类型：
--
作者：
N. Schneider;E. Lorenzo;P. Niiler
1937-1999年南加州海湾西南方向的水文观测表明，温度和盐度的年际变化差异很大。温度在温跃层内部和之上变化，并与厄尔尼诺、太平洋年代际振荡和局部上升流的气候指数相关。盐度变异性在近岸盐度最低的表层最大，并以十年时间尺度变化为特征。盐度异常与温度、跃层隆起和气候指数无关。计算表明，平均盐度梯度的长岸异常地转平流沿着加州海流的平均南向轨迹积累，并产生观测到的盐度变化。该平流过程的流量异常与大尺度气候指数无关。假设加州海流系统的低频变化是由地球磁场的变化引起的。
Abstract Hydrographic observations southwestward of the Southern California Bight in the period 1937–99 show that temperature and salinity variations have very different interannual variability. Temperature varies within and above the thermocline and is correlated with climate indices of El Nino, the Pacific decadal oscillation, and local upwelling. Salinity variability is largest in the surface layers of the offshore salinity minimum and is characterized by decadal-time-scale changes. The salinity anomalies are independent of temperature, of heave of the pycnocline, and of the climate indices. Calculations demonstrate that long-shore anomalous geostrophic advection of the mean salinity gradient accumulates along the mean southward trajectory along the California Current and produces the observed salinity variations. The flow anomalies for this advective process are independent of large-scale climate indices. It is hypothesized that low-frequency variability of the California Current system results from u...