Coupled Model Biases in the Sea Surface Temperature (SST) Distribution of the Global Tropics and their Influence on Climate Change Projections

全球热带海面温度（SST）分布的耦合模型偏差及其对气候变化预测的影响

• 批准号: 1650037
• 负责人: Bradfield Lyon
• 金额: $ 73.88万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-15 至 2022-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1650037&HistoricalAwards=false
• 关键词: Coupled; Model; Biases; Sea; Surface

Through their influence on the distribution of tropical rainfall and the atmospheric teleconnections, spatial variations in tropical sea surface temperatures play a major role in shaping regional climates both within, and outside, the tropics. How current sea surface temperature patterns may change under increasing greenhouse gas warming has therefore important implications for regional climate projections around the globe. A fundamental challenge in making such projections, however, is that the latest generation of coupled climate struggles to capture important aspects of the observed distribution of sea surface temperatures, confounding the interpretation of regional climate projections made by such models. The overall goal of the project is to evaluate the influence of coupled model tropical SST biases on regional climate and climate change projections around the globe. Through the use of atmosphere-only model simulations with specified sea surface temperatures, this project will first investigate how systematic biases in coupled model simulations of tropical sea surface temperatures in the current climate impact regional climates around the globe. The PIs will compare the regional climate response to the biases in tropical sea surface temperatures with the regional climate projections made by various coupled climate models to assess to what extent the regional climate projection uncertainties can be directly attributed to the regional climate responses to these biases. To further substantiate the attribution by the atmosphere-only model, they will build a hybrid coupled model with prescribed oceanic fluxes in order to minimize the coupled model biases. The hybrid model will then be used to produce future climate scenarios under increasing greenhouse gas concentrations. The future regional climate projections made by the hybrid model will be evaluated against their counterparts produced by fully coupled models. These two sets of innovative numerical experiments would help to narrow down the regional climate projection uncertainties.In addition to building on our physical understanding of the climate system, key findings from this project will be highly relevant to organizations working on climate change impacts and adaptation. Several of the project collaborators are already engaged with organizations focused on climate change impacts on agriculture and food security. Elements of this project will also be used in the professional development of both current and pre-service high school science teachers across Maine through an established partnership with the University of Maine. Summer workshops run by project collaborators will be held with current earth science teachers to foster the use of project-related climate data in their classrooms. The PIs will do periodic follow-up meetings with these teachers to evaluate the overall effectiveness of the effort.

通过对热带降雨分布和大气遥相关的影响，热带海洋表面温度的空间变化在塑造热带内外的区域气候方面发挥着重要作用。 因此，在温室气体变暖加剧的情况下，当前海面温度模式可能如何变化，对全球区域气候预测具有重要影响。然而，做出此类预测的一个根本挑战是，最新一代的耦合气候难以捕获观测到的海面温度分布的重要方面，从而混淆了此类模型对区域气候预测的解释。该项目的总体目标是评估耦合模型热带海温偏差对全球区域气候和气候变化预测的影响。通过使用具有特定海面温度的纯大气模型模拟，该项目将首先研究当前气候下热带海面温度耦合模型模拟中的系统偏差如何影响全球区域气候。 PI将把区域气候对热带海面温度偏差的响应与各种耦合气候模型做出的区域气候预测进行比较，以评估区域气候预测的不确定性在多大程度上可以直接归因于区域气候对这些偏差的响应。 为了进一步证实仅大气模型的归因，他们将建立一个具有规定海洋通量的混合耦合模型，以最大限度地减少耦合模型偏差。然后，混合模型将用于在温室气体浓度增加的情况下产生未来的气候情景。混合模型做出的未来区域气候预测将与完全耦合模型产生的对应模型进行评估。这两组创新的数值实验将有助于缩小区域气候预测的不确定性。除了建立我们对气候系统的物理理解之外，该项目的主要发现还将与致力于气候变化影响和适应的组织高度相关。 一些项目合作者已经与专注于气候变化对农业和粮食安全影响的组织合作。 通过与缅因大学建立的合作伙伴关系，该项目的要素还将用于缅因州现任和职前高中科学教师的专业发展。由项目合作者举办的夏季研讨会将与现任地球科学教师一起举办，以促进在课堂上使用与项目相关的气候数据。 PI 将与这些教师定期举行后续会议，以评估工作的整体有效性。

项目成果

Dynamical and Thermodynamic Elements of Modeled Climate Change at the East African Margin of Convection

东非对流边缘气候变化模拟的动力和热力学要素

• DOI: 10.1002/2017gl075486
• 发表时间: 2018-01-28
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: A. Giannini;B. Lyon;R. Seager;N. Vigaud
• 通讯作者: N. Vigaud

Biases in CMIP5 Sea Surface Temperature and the Annual Cycle of East African Rainfall

CMIP5海面温度的偏差和东非降雨量的年周期

• DOI: 10.1175/jcli-d-20-0092.1
• 发表时间: 2020-10-01
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: B. Lyon

Subseasonal convection variability over the Intra‐American Seas simulated by an AGCM and sensitivity to CMIP5 SST biases and projections

AGCM 模拟的美洲内海次季节对流变化以及对 CMIP5 海温偏差和预测的敏感性

• DOI: 10.1002/joc.6475
• 发表时间: 2020-01
• 期刊: International Journal of Climatology
• 作者: Vigaud, Nicolas;Lyon, Bradfield;Lee, Dong Eun
• 通讯作者: Lee, Dong Eun

Spatial Extents of Tropical Droughts During El Niño in Current and Future Climate in Observations, Reanalysis, and CMIP5 Models

观测、再分析和 CMIP5 模型中当前和未来气候中厄尔尼诺现象期间热带干旱的空间范围

• DOI: 10.1029/2021gl093701
• 发表时间: 2021-07
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Perez Arango, Juan D.;Lintner, Benjamin R.;Carvalho, Leila M. V.;Lyon, Bradfield
• 通讯作者: Lyon, Bradfield

Biases in sea surface temperature and the annual cycle of Greater Horn of Africa rainfall in CMIP6

CMIP6 中海面温度偏差和大非洲之角降雨年周期

• DOI: 10.1002/joc.7456
• 发表时间: 2021-11
• 期刊: International Journal of Climatology
• 作者: Lyon; Bradfield
• 通讯作者: Bradfield