Oettli Pascal, Morioka Yushi, Yamagata Toshio
Application Laboratory, Japan Agency for Marine-Earth Science and Technology, Yokohama, 236-0001, Japan.
Sci Rep. 2016 Jan 7;6:18782. doi: 10.1038/srep18782.
The interrannual variability of coastal sea surface temperature (SST) anomalies confined off Senegal is explored from a new viewpoint of the ocean-land-atmosphere interaction. The phenomenon may be classified into "coastal Niño/Niña" in the North Atlantic as discussed recently in the Northeastern Pacific and Southeastern Indian Oceans. The interannual variability of the regional mixed-layer temperature anomaly that evolves in boreal late fall and peaks in spring is associated with the alongshore wind anomaly, mixed-layer depth anomaly and cross-shore atmospheric pressure gradient anomaly, suggesting the existence of ocean-land-atmosphere coupled processes. The coupled warm (cold) event is named Dakar Niño (Niña). The oceanic aspect of the Dakar Niño (Niña) may be basically explained by anomalous warming (cooling) of the anomalously thin (thick) mixed-layer, which absorbs shortwave surface heat flux. In the case of Dakar Niña, however, enhancement of the entrainment at the bottom of the mixed-layer is not negligible.
从海洋 - 陆地 - 大气相互作用的新视角出发，探讨了局限于塞内加尔近海的沿海海表温度（SST）异常的年际变化。正如最近在东北太平洋和东南印度洋所讨论的那样，这种现象在北大西洋可归类为“沿海厄尔尼诺/拉尼娜”。在北半球晚秋发展并于春季达到峰值的区域混合层温度异常的年际变化，与沿岸风异常、混合层深度异常和跨岸大气压力梯度异常有关，这表明存在海洋 - 陆地 - 大气耦合过程。这种耦合的暖（冷）事件被命名为达喀尔厄尔尼诺（拉尼娜）。达喀尔厄尔尼诺（拉尼娜）的海洋方面基本上可以通过异常薄（厚）的混合层的异常变暖（变冷）来解释，该混合层吸收短波表面热通量。然而，在达喀尔拉尼娜的情况下，混合层底部夹卷作用的增强不可忽视。
