南京信息工程大学张荣华教授团队的最新研究报道了海洋叶绿素年际变化对厄尔尼诺的抵消效应和热带太平洋的热带不稳定波-尺度扰动。2023年12月6日，国际知名学术期刊《中国科学：地球科学》发表了这一成果。

研究采用了热带太平洋大气和海洋物理—生物地球化学(AOPB)的混合耦合模式(HCM)，分别在年际尺度和热带不稳定波尺度上，量化厄尔尼诺—南方涛动是如何被叶绿素扰动单独或共同调节的。基于混合耦合模式的敏感性实验证明了对厄尔尼诺的反作用：大尺度叶绿素年际变化引起的生物气候反馈，通过影响上层海洋分层和垂直混合来抑制厄尔尼诺—南方涛动，而热带不稳定波尺度叶绿素扰动引起的生物气候反馈则倾向于促进厄尔尼诺—南方涛动。

由于厄尔尼诺—南方涛动模拟敏感地依赖于叶绿素效应在这些不同尺度上的表现方式，因此有必要在气候模拟中充分考虑这些相关叶绿素效应的差异。研究阐明了一个与热带太平洋的叶绿素效应有关的厄尔尼诺—南方涛动模拟的偏差源，为该地区不同尺度的气候系统与海洋生态系统之间相互作用的提供了新见解。研究结果揭示了在年际和热带不稳定波尺度上，由叶绿素效应引起的厄尔尼诺—南方涛动调节的复杂性，这些复杂性与热带太平洋海洋生物地球化学过程及其与物理过程的相互作用有关。

据悉，在热带太平洋，叶绿素(Chl)的大扰动在年际和热带不稳定波(TIW)尺度上共存。目前，它们通过海洋生物诱导的加热(OBH)反馈对厄尔尼诺—南方涛动(ENSO)的综合影响方向上的研究较为薄弱。

附：英文原文

Title: Counteracting effects on ENSO induced by ocean chlorophyll interannual variability and tropical instability wave-scale perturbations in the tropical Pacific

Author: anonymous

Issue&Volume: 2023-12-06

Abstract: Large perturbations in chlorophyll (Chl) are observed to coexist at interannual and tropical instability wave (TIW) scales in the tropical Pacific; at present, their combined effects on El Niño-Southern Oscillation (ENSO) through ocean biology-induced heating (OBH) feedbacks are not understood well. Here, a hybrid coupled model (HCM) for the atmosphere and ocean physics-biogeochemistry (AOPB) in the tropical Pacific is adopted to quantify how ENSO can be modulated by Chl perturbations at interannual and TIW scales, individually or collectively, respectively. The HCM-based sensitivity experiments demonstrate a counteracting effect on ENSO: the bio-climate feedback due to large-scale Chl interannual variability acts to damp ENSO through its impact on upper-ocean stratification and vertical mixing, whereas that due to TIW-scale Chl perturbations tends to amplify ENSO. Because ENSO simulations are sensitively dependent on the ways Chl effects are represented at these different scales, it is necessary to adequately take into account these related differential Chl effects in climate modeling. A bias source for ENSO simulations is illustrated that is related with the Chl effects in the tropical Pacific, adding in a new insight into interactions between the climate system and ocean ecosystem on different scales in the region. These results reveal a level of complexity of ENSO modulations resulting from Chl effects at interannual and TIW scales, which are associated with ocean biogeochemical processes and their interactions with physical processes in the tropical Pacific.

DOI: 10.1007/s11430-023-1217-8

Source: https://www.sciengine.com/SCES/doi/10.1007/s11430-023-1217-8