SGER: Role of the Indian Ocean in Causing the Excessive Biennial El Nino-Southern Oscillation (ENSO) Tendency in NCAR's Community Climate Modeling System (CCSM3) Simulations

SGER：印度洋在导致 NCAR 社区气候模拟系统 (CCSM3) 模拟中两年一次的厄尔尼诺-南方涛动 (ENSO) 趋势过度中的作用

• 批准号: 0638432
• 负责人: Jin-Yi Yu
• 金额: --
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0638432&HistoricalAwards=false
• 关键词: SGER; Role; Indian; Ocean; Causing

Many coupled climate models, those with full representations of the atmosphere and ocean, are unable to simulate accurately the spatial structure and time evolution of the El Nino/Southern Oscillation (ENSO) phenomenon. ENSO is a leading mode of climate variability that affects regional weather and climate over much of the world. The current version of the Community Climate System Model (CCSM3) at the National Center for Atmospheric Research (NCAR) produces ENSO variability, but with an unrealistically strong two-year, or biennial, cycle. This deficiency, in one of the leading models used for projections of global climate change, reduces the reliability of such projections and their utility for predicting changes in regional climates. Based on his earlier model studies the PI hypothesizes that this unrealistic temporal variability in ENSO is a result of interactions between the tropical Pacific and Indian Oceans. He will test this hypothesis by conducting model experiments in which, rather than simulating sea-surface temperatures in the Indian Ocean, temperatures in this basin are imposed; the imposed temperatures will follow both a model generated and an observed annual cycle. If the excessive biennial variability of ENSO is reduced or eliminated in these experiments, it will indicate that the Indian Ocean climate is a significant source of the problem in the full model. This work will help to correct an important problem in a widely used, state-of-the-art, climate model and will contribute to training a graduate research assistant.

许多具有大气和海洋完整表征的耦合气候模型无法准确模拟厄尔尼诺/南方涛动（ENSO）现象的空间结构和时间演化。 ENSO 是气候变率的主要模式，影响世界大部分地区的区域天气和气候。国家大气研究中心 (NCAR) 的当前版本的社区气候系统模型 (CCSM3) 产生 ENSO 变化，但具有不切实际的两年或两年周期。用于预测全球气候变化的主要模型之一的这一缺陷降低了此类预测的可靠性及其预测区域气候变化的效用。根据他早期的模型研究，PI 假设 ENSO 这种不切实际的时间变化是热带太平洋和印度洋之间相互作用的结果。他将通过进行模型实验来检验这一假设，在模型实验中，不是模拟印度洋的海面温度，而是施加该盆地的温度；施加的温度将遵循生成的模型和观察到的年度周期。如果在这些实验中减少或消除ENSO过度的两年变率，则将表明印度洋气候是整个模型中问题的重要根源。这项工作将有助于纠正广泛使用的最先进的气候模型中的一个重要问题，并将有助于培训研究生研究助理。