Collaborative Research: Polar Amplification and High-Latitude Climate Sensitivity in Global Climate Models

合作研究：全球气候模型中的极地放大和高纬度气候敏感性

• 批准号: 0305098
• 负责人: Alexander Hall
• 金额: $ 13.98万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0305098&HistoricalAwards=false
• 关键词: Collaborative; Research; Polar; Amplification; Latitude

Climate models generally exhibit a poleward amplification of the surface air temperature increase that occurs in response to increased greenhouse gas levels. However, observational evidence of polar amplification during the 20th century is ambiguous, leading some to question the models' sensitivity. Furthermore, the wide range of high latitude sensitivity among models suggests disagreements remain regarding the physical processes responsible for poleward amplification. By means of this collaborative research project, the PIs will conduct a study to improve understanding of poleward amplication. A number of candidate feedback processes, including ice-albedo feedback, might affect high latitude climate sensitivity, and they will evaluate their relative impacts. Their approach is to perform sensitivity studies with one climate model, and to compare model sensitivity when the same sea ice component model is implemented in three different climate models. They will also analyze polar climate variations in a 15-member ensemble of 20th century simulations to explore possible attribution to internal variability or external forcing. They will also compare simulated and observed polar amplification. They plan to use the Community Climate System Model (CCSM) for much of the study, and compare the polar climate sensitivity of CCSM to the sensitivities of two other models, one from the Geophysical Fluid Dynamics Laboratory (GFDL) and the other from the Hadley Centre for Climate Prediction and Research. Together, these three models exhibit a wide range of polar amplification and global climate sensitivity. With their collaborators at these institutions, they plan to evaluate the role of sea ice physics in polar climate sensitivity by implementing the sea ice component from CCSM into the other two models. Then they will evaluate to what extent the range of sensitivity among the models depends on sea ice physics.Developing partnerships among modeling centers is a necessary step towards better understanding and simulation of polar climate sensitivity. This collaboration brings together scientists at the University of Washington, the University of California at Los Angeles, the National Center for Atmospheric Research, GFDL, and the Hadley Centre. The project will also support graduate students, who will be encouraged to visit modeling centers and attend conferences and workshops. In addition, results from this project will influence courses taught by the PIs. Finally, the simulations will be available immediately to all members of the CCSM Polar Climate Working Group, which is open to anyone.

气候模式一般显示，由于温室气体水平的增加，地表气温的升高会向极地方向放大。然而，20世纪极地放大的观测证据是模糊的，导致一些人质疑模式的敏感性。此外，模式间高纬度敏感性的大范围表明，对导致极地放大的物理过程仍存在分歧。通过这个合作研究项目，pi将进行一项研究，以提高对极地放大的理解。包括冰反照率反馈在内的一些候选反馈过程可能影响高纬度气候敏感性，他们将评估其相对影响。他们的方法是用一种气候模型进行敏感性研究，并在三种不同的气候模型中实施相同的海冰成分模型时比较模型的敏感性。他们还将在一个由15个成员组成的20世纪模拟集合中分析极地气候变化，以探索内部变率或外部强迫的可能原因。他们还将比较模拟和观测到的极性放大。他们计划在大部分研究中使用社区气候系统模型（CCSM），并将CCSM的极地气候敏感性与另外两个模型的敏感性进行比较，一个来自地球物理流体动力学实验室（GFDL），另一个来自哈德利气候预测与研究中心。这三种模式加在一起，表现出大范围的极地放大和全球气候敏感性。他们计划与这些机构的合作者一起，通过将CCSM中的海冰成分应用到其他两个模型中，来评估海冰物理在极地气候敏感性中的作用。然后，他们将评估模型之间的敏感性范围在多大程度上取决于海冰物理。在模拟中心之间发展伙伴关系是更好地理解和模拟极地气候敏感性的必要步骤。这次合作汇集了华盛顿大学、加州大学洛杉矶分校、国家大气研究中心、GFDL和哈德利中心的科学家。该项目还将支持研究生，鼓励他们参观建模中心，参加会议和研讨会。此外，这个项目的结果将影响到pi教授的课程。最后，模拟将立即提供给CCSM极地气候工作组的所有成员，该工作组对任何人开放。