Collaborative Research: An Observational and Modeling Study of Spring Onset in the Northern Hemisphere Circulation

合作研究：北半球环流春季爆发的观测和模拟研究

• 批准号: 0456188
• 负责人: Diane Portis
• 金额: --
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-15 至 2010-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0456188&HistoricalAwards=false
• 关键词: Collaborative; Research; Observational; Modeling; Study

The spring onset (i.e., yearly transition from winter to spring) and its interannual variability are important components of regional climate. These two features influence the hydrological cycle, through variations in clouds, sea ice, air temperature and ozone in the troposphere affecting humanity, vegetation growth, and ecosystem productivity. Recent observational studies have indicated that spring onset is strongly linked to stratospheric final warming (SFW). Past numerical studies have also indicated that the interannual variability in spring onset is strongly coupled to concomitant variations in the timing of the SFW events. The PIs' focus on SFW events provides a research setting for studying the physics and predictability of spring onset along with stratosphere-troposphere dynamical coupling that influences regional climate and its variability. Intellectual merit: The PIs will use a blend of synoptic and dynamic observational diagnoses and idealized modeling studies. First, a thorough phenomenological characterization of spring onset will be developed using observations. Then, the composite observational fields will be used to address various fundamental dynamical questions for spring onset. Guided by the phenomenological characterization and exploratory linear model calculations, several numerical experiments will be carried out to study stratosphere-troposphere coupling during spring onset. Completion of this work will offer new insights into:1. Effects of wave-mean flow interactions on the evolution of spring onset,2. Roles of the stratosphere in spring onset,3. Physical mechanisms responsible for noted changes in tropospheric climate and predictability.Broader impacts: The research provides a dynamical framework for understanding and interpreting regional climate changes associated with spring onset. It will have important implications for regional climate predictions. The research fosters collaboration between two universities and fills in gaps between tropospheric and stratospheric research communities and may lead to a comprehensive study of spring onset and its modulations by SFW events.

春季发作（即，从冬季到春季的年度过渡）及其年际变化是区域气候的重要组成部分。这两个特征通过影响人类，植被生长和生态系统生产率的对流层中云，海冰，空气温度和臭氧的变化影响水文周期。最近的观察性研究表明，春季发作与平流层最终变暖（SFW）密切相关。过去的数值研究还表明，春季发作的年际变异性与SFW事件的时机的伴随变化密切相关。 PIS对SFW事件的关注提供了研究环境，用于研究春季发作的物理和可预测性以及影响区域气候及其可变性的平流层 - 对流层动力耦合。智力优点：PI将使用概要和动态观察性诊断和理想化的建模研究的融合。首先，将使用观测值开发春季发作的彻底现象学表征。然后，复合观测场将用于解决春季发作的各种基本动力学问题。在现象学表征和探索性线性模型计算的指导下，将进行几个数值实验，以研究春季开始时研究平流层 - 对流层耦合。这项工作的完成将提供新的见解：1。波均流动相互作用对春季演变的影响，2。平流层在春季发作中的作用3。造成对流层气候和可预测性变化的物理机制。BROADER的影响：该研究为理解和解释与春季相关的区域气候变化提供了动态框架。 它将对区域气候预测具有重要意义。 该研究促进了两所大学之间的合作，并填补了对流层和平流层研究社区之间的空白，并可能导致对SFW事件对Spring发作及其调制的全面研究。