Further Studies of Dynamics for El Nino-Southern Oscillation (ENSO) Diversity and Complexity

这个更新项目的结果将提高气候模式预测厄尔尼诺-南方涛动（ENSO）及其影响和预测ENSO活动未来变化的能力。预计由首席研究员（PI）通过这一努力开发的理论和方法技术将在气候科学界具有广泛的适用性。科学成果的传播将通过出版物、在会议和专业会议上的演讲、夏威夷大学的渠道以及与当地和更广泛的社区的联系进行。通过该项目将培训一名研究生和两名早期职业科学家。每隔几年发生一次的厄尔尼诺/拉尼娜事件，其特征是热带太平洋东部大面积变暖/变冷，同时贸易风减弱/增强。全球气候系统这种强烈的年际波动被称为ENSO现象。它伴随着大气和海洋环流的系统性变化，影响全球天气和气候系统、海洋和陆地生态系统以及渔业，从而对经济福祉和人们的生活产生巨大影响。ENSO现象在其强度、持续时间和变暖/变冷模式及其全球影响方面表现出丰富的多样性。关于ENSO的基本问题仍有待更好地解决。例如，是否大致存在两组ENSO典型模式，即所谓的中太平洋和东太平洋厄尔尼诺现象，是科学界研究活跃的课题。此外，热带太平洋ENSO的影响如何扩散到高度复杂的全球气候系统和生态系统中，仍然是一个有待更好理解的问题。该项目将开展系统的理论、诊断和数值模拟研究，以实现以下三个目标：(1)进一步推进ENSO模式多样性起源的线性和非线性理论；(2)进一步了解ENSO复杂时间演变的机制及其影响；(3)进一步研究ENSO模式和时间特征对热带气候平均状态和气候模式关键物理过程参数偏差和未来变化的敏感性。将发展新的理论方法，并采用从简单到完全耦合的全球气候模型的模式层次来解决悬而未决的问题并实现这三个目标。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Results from this renewal project will improve the ability of climate models in predictions of El Nino-Southern Oscillation (ENSO), its impacts and in projections of future changes in ENSO activity. It is anticipated that the theoretical and methodological techniques that are developed by the Principal Investigator (PI) through this effort will have broad applicability in the climate science community. Dissemination of the scientific results will occur through publications, presentations at conferences and professional meetings, channels of the University of Hawaii, and outreach to the local and broader communities. A graduate student and two early-career scientists will be trained through this project.El Nino/La Nina events that occur every few years are characterized by massive warming/cooling over the eastern tropical Pacific Ocean together with weakening/strengthening of trade winds. This strong inter-annual fluctuation of the global climate system is referred to as the ENSO phenomenon. It accompanies by systematic changes in atmospheric and oceanic circulations, affecting global weather and climate systems, marine and terrestrial ecosystems, and fisheries, and thereby having a great impact on economics of well-being and people's life. The ENSO phenomenon exhibits rich diversity in its strength, duration and patterns of warming/cooling and in its global impacts. Fundamental issues concerning ENSO remain to be better addressed. For example, whether there exist roughly two groups of ENSO typical patterns, namely the so-called Central Pacific and Eastern Pacific El Nino is an active research topic in the scientific community. Furthermore, how influences of ENSO in the tropic Pacific are spread into the highly complex global climate system and ecosystem, remains a question to be better understood. The PI will conduct systematic theoretical, diagnostic, and numerical modeling investigations to achieve the following three objectives: (1) further advancing linear and nonlinear theories for the origins of the ENSO pattern diversity; (2) better understanding of the mechanisms causing ENSO complex temporal evolution and their impacts (3) further investigating the sensitivity of ENSO patterns and temporal characteristics to biases and future changes in tropical climate mean state and in parameters of key physical processes of the climate models. New theoretical approaches will be developed and a model hierarchy ranging from simple to fully coupled Global Climate Models will be adopted to address the outstanding questions and to achieve the three objectives.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.