Collaborative Research: Structure and Influence of Coherent Vertical Pulses of Wave Activity Flux in Observations and Models, from Daily to Seasonal Timescales

合作研究：从每日到季节时间尺度的观测和模型中波浪活动通量的相干垂直脉冲的结构和影响

• 批准号: 1657748
• 负责人: Judah Cohen
• 金额: $ 23.98万
• 依托单位: Atmospheric and Environmental Research Inc
• 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: 2017-08-15 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1657748&HistoricalAwards=false
• 关键词: Collaborative; Research; Structure; Influence; Coherent

The stratosphere, an atmospheric layer about 8-10 km above the surface, can influence winter weather over the Northern Hemisphere via its interactions with the troposphere beneath. These interactions can take several weeks to develop and mature, and may provide information about changes to weather patterns two to six weeks in advance, particularly during the fall and winter. An important starting point for some of these interactions is a change in the tropospheric winds over Northern Eurasia that occurs over a relatively short period, generally less than two weeks. This change in winds is associated with the "vertical pulses of wave activity flux", which can influence the polar stratosphere and, eventually, surface weather. This research aims to provide a comprehensive understanding of these short-term "pulse events" and their hemispheric influence by examining the spatial structure and temporal evolution of the events and investigating their role in the initiation of slower troposphere-stratosphere interactions that end up resulting in changes to weather over regions remote from the pulses, including over parts of North America, Europe, and Asia. This improved understanding will also provide an evaluation of the potential for considering these pulse events in the prediction of some aspects of weather variability up to several weeks in advance. The events will be studied using observational data for examining their structure and investigating their underlying physical mechanisms, and also using the output of weather forecast models to assess how realistically models are able to reproduce these events and their influence. This investigation will provide a better understanding of how the troposphere and stratosphere interact and of one of the causes of variations in winter weather. The project will also educate and train graduate students and include public outreach and education through development of a teaching portal, student presentation of tutorials through social media, and provision of an experimental forecast.

平流层是表面上方约8-10公里的大气层，可以通过与下面的对流层的相互作用来影响北半球的冬季天气。 这些相互作用可能需要数周才能发展和成熟，并且可能会提前两到六个星期提供有关天气模式变化的信息，尤其是在秋季和冬季。 这些相互作用中的一个重要的起点是，欧亚大陆北部的对流层风发生了变化，这在相对较短的时间内发生，通常不到两周。 风的这种变化与“波活性通量的垂直脉冲”有关，这会影响极地平流层以及最终的表面天气。 这项研究旨在通过检查事件的空间结构和时间演变，并研究它们在对流层 - 线圈相互作用缓慢的启动中的作用，从而使对对流层的较慢相互作用的作用最终导致远离脉冲的天气变化，包括北部北部的脉冲，包括北部美国，欧洲，欧洲和ASASIA。这种改善的理解还将评估考虑这些脉搏事件的潜力，以预测最长达几周的天气变异性方面。 这些事件将使用观察数据研究以检查其结构并研究其潜在的物理机制，并使用天气预报模型的输出来评估现实模型如何能够重现这些事件及其影响力。这项研究将更好地了解对流层和平流层如何相互作用以及冬季天气变化的原因之一。 该项目还将教育和培训研究生，并通过开发教学门户网站，通过社交媒体的教程演讲以及提供实验预测，包括公众推广和教育。

项目成果

The role of stratospheric ozone for Arctic-midlatitude linkages

• DOI: 10.1038/s41598-019-43823-1
• 发表时间: 2019-05
• 期刊: Scientific Reports
• 影响因子: 4.6
• 作者: Erik Romanowsky;D. Handorf;Ralf Jaiser;I. Wohltmann;W. Dorn;J. Ukita;J. Cohen;K. Dethloff;M. Rex

Divergent consensuses on Arctic amplification influence on midlatitude severe winter weather

• DOI: 10.1038/s41558-019-0662-y
• 发表时间: 2020-01-01
• 期刊: NATURE CLIMATE CHANGE
• 影响因子: 30.7
• 作者: Cohen, J.;Zhang, X.;Yoon, J.
• 通讯作者: Yoon, J.

The different stratospheric influence on cold-extremes in Eurasia and North America

• DOI: 10.1038/s41612-018-0054-4
• 发表时间: 2018-01-01
• 期刊: NPJ CLIMATE AND ATMOSPHERIC SCIENCE
• 影响因子: 9
• 作者: Kretschmer, Marlene;Cohen, Judah;Coumou, Dim
• 通讯作者: Coumou, Dim