New data on the presence of ¹²⁹I in seawater in the Southern Hemisphere measured by Accelerator Mass Spectrometry (AMS) is presented. The samples were collected in 2014 along the Namibian coast during a cruise organised by the National Marine Information and Research Centre (NatMIRC), the national laboratories of the Ministry of Fisheries and Marine Resources (MFMR) in Namibia, and the IAEA Environment Laboratories (IAEA NAEL) in Monaco. The Benguela upwelling system is known as one of the most important marine upwelling regions in the world. Strong winds induce an offshore transport of surface seawater which is substituted by cool subsurface water inshore. As this water is nutrient-rich, which leads to high primary productivity, the Benguela upwelling system has a very important role as a fishing production area. The ¹²⁹I concentrations in samples were between (0.66 ± 0.14) × 10⁷ and (1.45 ± 0.30) × 10⁷ atoms/kg. The highest ¹²⁹I concentrations were found in the offshore surface samples. Deep-sea and inshore samples contained lower ¹²⁹I concentrations, possibly as an effect of the upwelling process. A comparison with previously published studies suggests that the presence of ¹²⁹I in the northern Benguela upwelling system (nBUS), is mainly due to the impact of nuclear weapons global fallout, without any evident impact of nuclear fuel reprocessing.

关于^129的新数据介绍了通过加速器质谱（AMS）测量的南半球海水中的I。国家海洋信息和研究中心（NatMIRC），纳米比亚渔业和海洋资源部（MFMR）国家实验室以及国际原子能机构环境实验室（IAEA）于2014年在纳米比亚海岸巡游期间收集了这些样品。 NAEL）。Benguela上升流系统被称为世界上最重要的海洋上升流区域之一。强风引起了表层海水的近海运输，被近海中的地下凉水代替。由于该水营养丰富，可提高初级生产力，因此本格拉上升流系统作为捕鱼区非常重要。在¹²⁹样品中的I浓度在（0.66±0.14）×10 ⁷和（1.45±0.30）×10 ⁷原子/ kg之间。在离岸地表样品中发现最高的¹²⁹ I浓度。深海和近海样品含有较低的¹²⁹ I浓度，可能是由于上升过程的影响。与先前发表的研究进行的比较表明，北本格拉上升流系统（nBUS）中存在¹²⁹ I的主要原因是核武器全球尘埃的影响，而对核燃料后处理没有任何明显影响。