Duprey N N, Foreman A D, Carriquiry J D, Charles C D, Sanchez S C, Vonhof H, Rubach F, Rabenstein R, Rohr M, Reyes-Bonilla H, Marconi D, Sigman D M, Haug G H, Martínez-García A
Max Planck Institute for Chemistry (Otto Hahn Institute), Mainz, Germany.
Terracoast Environmental Consultants, Ensenada, Baja California, México.
Science. 2024 Nov 29;386(6725):1019-1024. doi: 10.1126/science.adk4965. Epub 2024 Nov 28.
The impact of global warming on the ocean's oxygen-deficient zones (ODZs) is uncertain, partly because of a lack of data on past changes. We report monthly resolved records of coral skeleton-bound nitrogen isotopes (CS-δN) to reconstruct denitrification in the Eastern Tropical North Pacific (ETNP) ODZ over the last 80 years. The data indicate strong decadal variation in ETNP denitrification, with maxima during the cool North Pacific phase of Pacific Decadal Variability. The maxima in denitrification (and thus oxygen deficiency) were likely due to stronger upwelling that enhanced productivity leading to greater oxygen demand in the thermocline. Prior findings of multidecadal-to-centennial ODZ trends were likely biased by this variability. ODZ evolution over the next century will depend on how global warming interacts with the decadal oscillations.
全球变暖对海洋缺氧区（ODZs）的影响尚不确定，部分原因是缺乏过去变化的数据。我们报告了珊瑚骨骼结合氮同位素（CS-δN）的月度解析记录，以重建过去80年东热带北太平洋（ETNP）缺氧区的反硝化作用。数据表明，ETNP反硝化作用存在强烈的年代际变化，在太平洋年代际变率的冷北太平洋阶段达到最大值。反硝化作用（进而导致缺氧）的最大值可能是由于更强的上升流增强了生产力，导致温跃层中的氧气需求增加。此前关于年代际至百年尺度ODZ趋势的研究结果可能受到这种变率的影响。下个世纪ODZ的演变将取决于全球变暖如何与年代际振荡相互作用。
