University of Guam Marine Laboratory, UOG Station, Mangilao, GU, 96923, USA.
Yap Community Action Program, Colonia, Yap, FM. 96943, Federated States of Micronesia.
Sci Rep. 2020 May 8;10(1):7735. doi: 10.1038/s41598-020-64411-8.
El Niño Southern Oscillation (ENSO) events modulate oceanographic processes that control temperature and productivity in tropical waters, yet potential interactions with low frequency climate variability, such as the Pacific Decadal Oscillation (PDO), are poorly understood. We show that ENSO and PDO together predicted (i) maximum sea-surface temperatures (SST), which were associated with coral bleaching and declines in coral cover, and (ii) maximum chlorophyll-a concentrations, which were associated with high densities of coral-predatory Acanthaster starfish, across the tropical north Pacific Ocean since 1980. Asynchrony between the positive PDO and negative ENSO (i.e., La Niña) was associated with peaks in annual SST. By contrast, synchrony between the positive PDO and positive ENSO (i.e., El Niño) was associated with peaks in chlorophyll-a. Both conditions led to ecological disturbances and significant loss of coral cover, however, spatial models revealed where impacts to reefs were expected under varying climate scenarios. The 2015/17 ENSO event was coupled with a positive PDO and resulted in high SST and Acanthaster abundances in eastern Micronesia, while positive coral growth occurred in western Micronesia. Our novel approach for forecasting coral growth into the future may be applicable to other oceanic regions with differing oceanographic modulators.
厄尔尼诺南方涛动（ENSO）事件调节控制热带水域温度和生产力的海洋过程，但与低频气候变化，如太平洋十年涛动（PDO）的潜在相互作用仍了解甚少。我们表明，ENSO 和 PDO 共同预测了（i）最大海面温度（SST），这与珊瑚白化和珊瑚覆盖率下降有关，以及（ii）最大叶绿素-a 浓度，这与珊瑚捕食性棘冠海星的高密度有关，自 1980 年以来，整个北太平洋热带地区都存在这种情况。PDO 为正而 ENSO（即拉尼娜）为负的非同步性与年度 SST 的峰值有关。相比之下，PDO 为正而 ENSO 为正（即厄尔尼诺）与叶绿素-a 的峰值有关。这两种情况都导致了生态干扰和珊瑚覆盖率的显著下降，但空间模型揭示了在不同气候情景下预计对珊瑚礁的影响。2015/17 年的 ENSO 事件与正 PDO 相关，导致密克罗尼西亚东部的 SST 和棘冠海星数量较高，而西密克罗尼西亚的珊瑚生长呈阳性。我们预测珊瑚生长的新方法可能适用于其他具有不同海洋调制器的海洋区域。
