Analyses of Large-scale Climate Variability: Understanding Periodicity in the Extratropical Storm Tracks

大尺度气候变率分析：了解温带风暴路径的周期性

• 批准号: 1734251
• 负责人: David Thompson
• 金额: $ 69.79万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1734251&HistoricalAwards=false
• 关键词: Analyses; Large; scale; Climate; Variability

Weather systems appearing on daily maps are driven by the temperature contrast between the tropics and the poles, which is expressed dynamically as the baroclinicity of the atmosphere, or the variation of pressure on surfaces of constant density. Pressure differences on density surfaces produce a pressure gradient force, which provides the kinetic energy that powers weather systems and the winds associated with them. Recently the PI demonstrated that the interplay between baroclinicity and kinetic energy (in this case referred to as eddy kinetic energy or EKE), results in variations in the vigor of weather activity with a period between 20 and 25 days (see AGS-1343080). The 20-25 day oscillation was documented in the longitudinally averaged EKE of the Southern Hemisphere and has an annular structure with peak amplitude near the center of the storm track. The mode is thus referred to as the Southern Baroclinic Annular Mode (SBAM), and the PI has identified a comparable although weaker counterpart, the NBAM, in the Northern Hemisphere.Work funded here seeks to develop a physical understanding of the modes, using a combination of observational data analysis and model simulations to understand why the modes exist and what determines their periodicity, spatial structure, relationship to individual weather systems, and other characteristics. The work also considers the implications of the modes for practical weather forecasting, in part by examining their predictability in the forecasts archived as part of the Seasonal to Subseasonal Prediction Project (performed under the auspices of the World Meteorological Organization).The research is of societal as well as scientific interest due to the possible implications of predictable oscillations in weather activity for long-range forecasting. The PI and his group also perform outreach to the local school district through presentations to students and teachers on the science of weather and climate. In addition, the project supports two graduate students, thereby providing for the future workforce in this research area.

出现在每日地图上的天气系统是由热带和两极之间的温度差异驱动的，这种差异动态地表示为大气的斜压性，或密度恒定的表面上的压力变化。密度表面上的压力差产生压力梯度力，它提供动能，为天气系统和与之相关的风提供动力。最近，PI证明了斜压性和动能（在这种情况下称为涡流动能或EKE）之间的相互作用，导致天气活动活力的变化，周期在20到25天之间（见AGS-1343080）。20 ~ 25 d的振荡记录在南半球的经线平均EKE上，呈环状结构，振幅峰值位于风暴路径中心附近。因此，这种模式被称为南斜压环模（SBAM），而PI已经在北半球发现了一个类似的，尽管较弱的对应物nbaam。这里资助的工作旨在发展对模式的物理理解，结合观测数据分析和模式模拟来理解模式存在的原因，以及是什么决定了它们的周期性、空间结构、与单个天气系统的关系和其他特征。这项工作还考虑了模式对实际天气预报的影响，部分是通过检查它们在作为季节到亚季节预测项目（在世界气象组织主持下执行）的一部分存档的预报中的可预测性。由于天气活动的可预测振荡可能对长期预报产生影响，因此这项研究具有社会和科学意义。PI和他的团队还通过向学生和老师介绍天气和气候科学，向当地学区进行推广。此外，该项目还支持两名研究生，从而为该研究领域的未来劳动力提供支持。

项目成果

Quantifying the Role of Ocean Dynamics in Ocean Mixed Layer Temperature Variability

量化海洋动力学在海洋混合层温度变化中的作用

• DOI: 10.1175/jcli-d-20-0476.1
• 发表时间: 2021
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Patrizio, Casey R.;Thompson, David W.
• 通讯作者: Thompson, David W.

On the Observed Relationships between Wintertime Variability in Kuroshio–Oyashio Extension Sea Surface Temperatures and the Atmospheric Circulation over the North Pacific

• DOI: 10.1175/jcli-d-17-0343.1
• 发表时间: 2018-05
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Samantha M. Wills;D. Thompson

The Role of Tropical, Midlatitude, and Polar Cloud-Radiative Changes for the Midlatitude Circulation Response to Global Warming

热带、中纬度和极地云辐射变化对中纬度环流对全球变暖响应的作用

• DOI: 10.1175/jcli-d-20-0073.1
• 发表时间: 2020
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Albern, Nicole;Voigt, Aiko;Thompson, David W.;Pinto, Joaquim G.
• 通讯作者: Pinto, Joaquim G.

The 2019 Southern Hemisphere Stratospheric Polar Vortex Weakening and Its Impacts

• DOI: 10.1175/bams-d-20-0112.1
• 发表时间: 2021-06-01
• 期刊: BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
• 影响因子: 8
• 作者: Lim, Eun-Pa;Hendon, Harry H.;Wang, Guomin
• 通讯作者: Wang, Guomin

On the Seasonal Evolution and Impacts of Stratosphere-Troposphere Coupling in the Southern Hemisphere.

南半球平流层-对流层耦合的季节演变及影响。

• 发表时间: 2018
• 期刊: Journal of geophysical research
• 作者: Lim, Eun-Pa;Hendon, H. H.;Thompson, D. W.
• 通讯作者: Thompson, D. W.