The influence of long, sub-inertial waves travelling poleward on spatiotemporal fluctuations in the hydrography of coastal upwelling areas has widely been discussed theoretically in the literature since the late 1970s. In this paper, in contrast, measured unexpected wave-like changes in the intermediate density field along the Namibian continental slope are presented and suggested to be the result of a geostrophically adjusted southward current with significant on-offshore meanders. Hydrographic measurements had been carried out on board of r/v ‘METEOR’ along the 200-m isobath above the Namibian continental shelf (19–23 °S) during seven days in October/November 2000. Measured water properties rhythmically change in space between oceanic (on-shore meander, well oxygenated, dominant Eastern South Atlantic Central Water, ESACW) and coastal waters (off-shore meander, poorly oxygenated, dominant South Atlantic Central Water, SACW). The first case is accompanied by downward displacements of the permanent pycnocline, while the second one corresponds to the opposite situation. The distance between these rather periodic along-section changes in stratification is roughly constant and estimated to be about 60 km. At two hydrographic station positions, duplicate measurements enable an estimation of the associated southward propagation speed of the signal. The obtained value of about 0.16 m/s roughly peaks at the pressure level of about 70 dbar, and the corresponding time scale is estimated to be a few days.

自1970年代后期以来，在理论上已经广泛地讨论了长的亚惯性波极地传播对沿海上升流区的水文学时空波动的影响。相反，在本文中，提出了沿纳米比亚大陆坡测量的中间密度场中意想不到的波浪状变化，并认为这是经过地转调整后的南向洋流的结果，该洋流具有明显的近海曲折。水文测量是在2000年10月/ 11月的7天内，沿着纳米比亚大陆架（19-23°S）上方200米等深线的r / v“ METEOR”船上进行的。海洋（陆上蜿蜒，含氧量高，南大西洋东部主要的中央水域，ESACW）和沿海水域（近海曲折，含氧量低，占主导地位的南大西洋中央水域SACW）。第一种情况是永久性比克辛啉向下移位，而第二种情况则相反。分层中这些相当周期性的横截面变化之间的距离大致恒定，估计约为60 km。在两个水文站的位置，重复测量可以估算信号的相关向南传播速度。所获得的约0.16 m / s的值在约70 dbar的压力水平上大致达到峰值，相应的时间范围估计为几天。而第二个则相反。分层中这些相当周期性的横截面变化之间的距离大致恒定，估计约为60 km。在两个水文站的位置，重复测量可以估算信号的相关向南传播速度。所获得的约0.16 m / s的值在约70 dbar的压力水平上大致达到峰值，并且相应的时间范围估计为几天。而第二个则相反。这些分层中相当周期性的横截面变化之间的距离大致恒定，估计约为60 km。在两个水文站的位置，重复测量可以估算信号的相关向南传播速度。所获得的约0.16 m / s的值在约70 dbar的压力水平上大致达到峰值，并且相应的时间范围估计为几天。