Collaborative Research: NSF-BSF--Tropospheric Response to Zonal Asymmetry of the Stratospheric Polar Vortex and Its Aapplication to Subseasonal to Seasonal (S2S) Prediction

合作研究：NSF-BSF--平流层极地涡旋纬向不对称性的对流层响应及其在次季节到季节（S2S）预测中的应用

• 批准号: 2140909
• 负责人: Judah Cohen
• 金额: $ 34.57万
• 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: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2140909&HistoricalAwards=false
• 关键词: Collaborative; Research; NSF; BSF; Tropospheric

The stratosphere is the layer of the atmosphere that sits above the clouds and storms that affect weather at the earth's surface. But despite being above the weather the stratosphere still influences the weather, particularly when the eastward-moving vortex that forms in winter over the polar cap breaks down in events called sudden stratospheric warmings (SSWs). The expected tropospheric response to an SSW is higher surface pressure over the polar cap, more frequent occurrence of cold air outbreaks, and and more frequent coastal Nor'easter storms. SSWs are thus of great interest for subseasonal to seasonal (S2S) weather prediction, and the mechanisms through which SSWs influence surface weather have been intensively studied. Work under this award seeks to improve understanding of the effects of SSWs and other less extreme stratospheric polar vortex disruptions on tropospheric circulation and surface weather. A key issue is that some SSWs have a strong effect on the underlying troposphere while others do not, and the distribution of surface temperature anomalies can be quite different from one polar vortex disruption to another. The Principal Investigators hypothesize that differences in the tropospheric response are due in part to the pattern of distortions that occur over the course of a polar vortex disruption. For instance in some SSWs a "daughter" vortex forms after the stratospheric polar vortex breaks down, and the surface temperature response could vary depending on the location of the daughter vortex.The research involves analysis of observational datasets, output from simulations available through the Coupled Model Intercomparison Project (CMIP), and ensembles of subseasonal to seasonal (S2S) forecasts and hidcasts including those available through the National Multi-Model Ensemble (NMME). The data analysis effort is complemented by simulations from the Model of an Idealized Moist Atmosphere (MIMA), a simplified model capable of simulating realistic features of the Norhtern Hemisphere winter circulation including jet streams, stationary waves, and the stratospheric polar vortex. Experiments are conducted by using an artificial drag force to induce vortex disruptions with specific geographical distortions so that their effects on surface temperature can be assessed.The work is of societal as well as scientific interest given the connection between stratospheric vortex disruptions and extreme winter weather. One of the Principal Investigators maintains a blog that serves as a portal for technical and non-technical discussion of present and forecasted weather patterns for the Northern Hemisphere. The project also provides support and training for a graduate student and a postdoctoral associate.This is a project jointly funded by the National Science Foundation's Directorate of Geosciences (NSF-GEO) and the Israel Binational Science Foundation (BSF) in accord with the language in the Memorandum of Understanding between the NSF and the BSF. This Agreement allows a single collaborative proposal, involving US and Israeli investigators, to be submitted and peer-reviewed by NSF. Upon successful results of the NSF merit review and recommendation by the cognizant NSF Program of an award, each Agency funds the proportion of the budget and the investigators associated with its own country.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

平流层是位于影响地球表面天气的云层和风暴上方的大气层。 但是，尽管天气高于天气，但平流层仍会影响天气，尤其是当在冬季形成的向东移动的涡流在极性帽上形成，这在称为突然的平流层变暖（SSW）的事件中。 预期的对流层对SSW的反应是极地盖上更高的表面压力，更频繁的冷空气暴发以及更频繁的沿海Nor'easter风暴。因此，SSW对季节性到季节性（S2S）天气预测以及SSW影响地面天气的机制非常感兴趣。该奖项下的工作旨在提高人们对SSW和其他不太极端平流层极性涡旋对对流层循环和表面天气的影响。 一个关键问题是，某些SSW对对流层具有很强的影响，而其他SSW则没有，而表面温度异常的分布可能与一种极性涡流中断到另一种极性涡流中的分布。 主要研究人员假设对流层反应的差异部分是由于在极地涡流中断过程中发生的扭曲模式。 例如，在一些SSW中，平流层极性涡流分解后一种“女儿”涡旋形成，并且表面温度响应可能会因女儿涡流的位置而异。研究涉及观察数据集的分析，通过耦合模型对间年间项目（CMIP）（CMIP）以及季节性群体（S2S）（S2S）（S2S2S）（S2S2S）（S2S2S）（S2S2S）的模拟分析。多模型合奏（NMME）。 来自理想化潮湿气氛（MIMA）模型的模拟来补充了数据分析工作，这是一个简化的模型，该模型能够模拟Norhtern Hemisphere冬季循环的现实特征，包括喷气流，固定波和平流层极性涡流。 实验是通过使用人工阻力来诱导特定地理扭曲的涡流中断进行的，以便评估其对表面温度的影响。鉴于平流层涡流中断与极端冬季天气之间的联系，这项工作具有社会和科学兴趣。 一位主要研究人员保留了一个博客，可作为北半球当前和预测天气模式的技术和非技术讨论的门户网站。 该项目还为研究生和博士后同事提供了支持和培训。该项目是由国家科学基金会地球科学局（NSF-GEO）和以色列双性科学基金会（BSF）共同资助的项目，该项目与NSF和BSF之间的纪念性语言中的语言一致。该协议允许NSF提交和同行评审，涉及我们和以色列调查人员的单一协作提案。根据NSF绩效审查的成功结果和奖励的NSF计划的建议，每个机构都资助了预算的比例以及与其自己的国家相关的调查人员的比例。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的审查标准来通过评估来通过评估来获得支持的。