Collaborative Research: Persistent Wintertime Temperature Inversions in the Salt Lake Basin

一项为期三年的研究项目将调查导致盐湖盆地（SLB）形成的持续、多日、冬季中期温度逆温或冷空气池的形成、维持和破坏的过程。这些持续的逆温也经常发生在美国西部和世界各地的其他地区，它们的开始和破裂很难预测。在持续逆温期间，城市流域的空气污染可能达到不可接受的高水平，当逆温破裂时，破裂可以垂直携带污染，产生区域尺度的空气污染和气候影响。由于混合不良，雾和层云会在逆温中积聚，导致持续的冻雨、毛毛雨或雾的危险事件，并干扰地面交通和航空。该项目的目标是：1)确定导致持续逆温形成、维持和破裂的气象过程；2)确定这些过程对城市流域空气污染运输和扩散的影响；3)确定如何改进气象模式，以提供更准确的持续逆温模拟。该项目包括观察、分析和建模。最初的重点将是利用现有气象数据对2000-2001年冬季的一个事件进行建模。对最近事件研究的分析将确定在这种情况下导致持续逆温形成和破坏的关键物理机制。2010年12月1日至2011年2月7日将在SLB进行一次野外试验，以获得进一步模式模拟和分析所需的更多案例的详细气象数据。中尺度气象模式将用于解释观测结果，验证假设，进一步了解物理机制，并评估逆温过程对空气污染的影响。模拟将考虑到在SLB逆温中形成和消散的经常观测到的雾和层状云。智力优势：该项目将促进对影响持续逆温的物理过程的认识和理解。这种知识的增长预计将导致模型的改进，并最终改善美国西部和全世界的天气预报。这项工作采用了创新的方法，采用了早期研究产生的相关物理过程的概念模型，并结合了对先前数据的分析和新数据的收集以及数值模拟来获得理解。更广泛的影响：通过将研究整合到大学教学中，通过对本科生和研究生的支持，通过促进研究者/学生的多样性，促进更广泛的社会影响。项目成果将通过同行评议的科学出版物和报告广泛传播。研究结果通过提高对冷池的理解对社会有潜在的好处，并有可能应用于更好地了解空气污染扩散、天气预报和气候。

A three-year research project will be conducted to investigate processes leading to the formation, maintenance and destruction of persistent, multi-day, mid-winter temperature inversions or cold-air pools that form in the Salt Lake basin (SLB). These persistent inversions occur frequently as well in other regions throughout the western US and throughout the world, and their initiation and breakup are quite difficult to forecast. Air pollution can reach unacceptably high levels during persistent inversions in urban basins, and when the inversion breaks the breakup can carry pollution vertically to produce regional-scale air pollution and climate impacts. Because of poor mixing, fog and stratus can build up in the inversion leading to hazardous episodes of persistent freezing rain, drizzle or fog and interfering with ground transportation and aviation.The objectives of the project are to 1) identify the meteorological processes that lead to buildup, maintenance and breakup of persistent inversions, 2) determine the consequences of these processes on air pollution transport and diffusion in urban basins, and 3) determine how meteorological models can be improved to provide more accurate simulations of such persistent inversions.The project includes observations, analysis, and modeling. The initial focus will be modeling of an event in the winter of 2000-2001 using existing meteorological data. The analyses of this recent event study will identify the key physical mechanisms leading to persistent inversion formation and destruction in this case.A field experiment will be conducted in the SLB from 1 Dec 2010 to 7 Feb 2011 to obtain the detailed meteorological data on several more cases needed for further model simulations and analyses. A mesoscale meteorological model will be used to interpret the observations, verify hypotheses, provide further insight into physical mechanisms, and evaluate the air pollution implications of the inversion processes. The simulations will take account of the often-observed fog and stratiform clouds that form and dissipate within the SLB inversions.Intellectual Merit: The project will advance knowledge and understanding of the physical processes that affect persistent inversions. This increase in knowledge is expected to lead to improvements in models and, ultimately, in weather forecasts for the western U.S. and throughout the world. The work uses innovative approaches, employs conceptual models of relevant physical processes resulting from earlier research, and uses a combination of analyses of prior data and collection of new data and numerical modeling to gain understanding.Broader Impacts: Broader societal impacts are promoted through the integration of the research into university teaching, through the support of undergraduate and graduate students and through the promotion of investigator/student diversity. Project results will be widely disseminated through peer-reviewed scientific publications and presentations. The results have potential benefits to society through improved understanding of cold pools with potential applications for better understanding air pollution dispersion, weather forecasting and climate.