P2C2: Constraining Mechanisms of Tropical Climate Change Using Simulations and Proxies of the Last Glacial Maximum (LGM)

P2C2：利用末次盛冰期 (LGM) 的模拟和代理来约束热带气候变化的机制

• 批准号: 1204011
• 负责人: Pedro Di Nezio
• 金额: $ 32.89万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1204011&HistoricalAwards=false
• 关键词: P2C2; Constraining; Mechanisms; Tropical; Climate

The Last Glacial Maximum (LGM), that period of time 21,000 years ago when the earth was glaciated and significantly colder than today, provides a unique set of boundary conditions to test climate general circulation models. This proposal aims to use simulations of the LGM to determine if the Walker Circulation, a coupled atmosphere-ocean system in the tropical Pacific, was stronger or weaker at that time. The project will attempt to address several important questions including: 1) How important are changes in the hydrological cycle, sea surface temperature gradients, and exposure of the Sunda shelf in affecting past intensity of the Walker Circulation? 2) What is the impact of model bias in the interaction among these mechanisms? 3) Can the different reconstructions of past climate in the tropical Pacific be reconciled and used to constrain each of these mechanisms? 4) How well do state-of-the-art climate models simulate the response of the Walker circulation to the exposure of the Sunda shelf due to lower sea level during the LGM.The models to be used in the study were also used to produce key paleoclimate simulations that will be discussed in the IPCC AR5 reports. Thus the evaluation of the performance of the different models will be very valuable to the climate research community.

末次盛冰期 (LGM) 是 21,000 年前的那段时期，当时地球被冰川覆盖，温度比今天低得多，它提供了一组独特的边界条件来测试气候环流模型。该提案旨在利用末次盛宴的模拟来确定沃克环流（热带太平洋的大气-海洋耦合系统）当时是更强还是更弱。 该项目将尝试解决几个重要问题，包括：1）水文循环、海面温度梯度和巽他陆架的暴露程度的变化对沃克环流过去强度的影响有多重要？ 2）模型偏差对这些机制之间的相互作用有何影响？ 3）对热带太平洋过去气候的不同重建是否可以协调并用于约束这些机制？ 4) 最先进的气候模型模拟沃克环流对末次盛冰期海平面较低导致巽他陆架暴露的反应效果如何。研究中使用的模型也被用来产生IPCC AR5 报告中将讨论的关键古气候模拟。 因此，评估不同模型的性能对于气候研究界来说非常有价值。