Rossby Wave Breaking Archetypal Patterns, Processes and Projected Changes from the 20th (twentieth) to the 21st (twenty-first) Century

通常发生在中纬度地区的天气部分是由高速气流驱动的——高速气流是在地面以上8-13公里处形成的强风走廊——以及与之一起传播的罗斯比波相关的大气波动。这些波浪通常有一种类似于海洋中的涌浪的模式，因为它们相对宽阔且翻滚。然而，在某些情况下，它们会破裂，就像波浪在海岸线上破碎一样。当罗斯比波在大气中破裂时，它们通常与高影响的天气现象有关，比如延长的热波和冷波、极端降水和大气阻塞，这些都会显著改变急流的路径。这些罗斯比波浪可以呈现各种不同的形状和大小（即口味），这可能决定了它们在哪里以及如何调节中纬度极端天气。到目前为止，还没有对不同的破波口味进行全面的分析。这项研究的目标是利用机器学习来了解北半球在当前和未来气候下的罗斯比波破裂的共同特点。研究人员将在过去的观测中评估罗斯比波浪破碎的味道，并试图确定气候模型能在多大程度上代表这种模式，以及它们对急流和天气的相关影响。拟议的工作还将探索这些罗斯比波破裂的味道、频率和影响在21世纪可能发生的变化。鉴于罗斯比波破裂、急流和高影响天气之间的密切联系，更好地了解这些事件在现在和未来具有重要的社会意义。对罗斯比波浪破碎模式在下个世纪如何变化的探索，将揭示科学界和广大公众都感兴趣的一个关键领域。作为拟议活动的一部分，调查人员将指导一名研究生和两名本科生。一名本科生研究员将帮助开发用于业务预报员的实时罗斯比波浪破碎跟踪工具，而另一名研究员将探索罗斯比波浪破碎对气候敏感的地中海地区变化的影响。因此，这项研究将有助于提高我们对这些高影响事件的基本认识，培养天气和气候交叉研究的下一代科学家，并为研究界成员、业务预报员和政策/适应决策者提供感兴趣的信息。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The weather that typically occurs in the middle latitudes is driven in part by the jet stream - a corridor of strong winds found 8-13 km above ground - and atmospheric undulations associated with Rossby waves that propagate with it. These waves typically have a pattern that resembles a swell in the ocean, in that they are relatively broad and rolling. However, in certain circumstances, they can break, resembling closely the appearance of a wave breaking on a shoreline. When Rossby waves break in the atmosphere, they are frequently associated with high-impact weather phenomena like extended heat and cold waves, extreme precipitation, and atmospheric blocking that can significantly alter the path of the jet stream. These Rossby wave breaks can take on a variety of different shapes and sizes (i.e., flavors) which may determine where and how they modulate mid-latitude extreme weather. To date, a comprehensive analysis of the different wave breaking flavors has yet to be undertaken. The goal of this research is to understand the common flavors of Rossby wave breaking in the Northern Hemisphere in the present and future climate using machine learning. The investigators will assess the flavors of Rossby wave breaking in past observations and seek to identify how well climate models can represent such patterns and their associated impacts on the jet stream and weather. The proposed work will also explore how these Rossby wave break flavors, frequencies, and impacts may change over the 21st Century. Given the close linkage between Rossby wave breaking, the jet stream, and high-impact weather, a better understanding of these events in the present and future is societally important. The exploration of how Rossby wave break patterns change over the next century should shed light on a critical area of interest to both the science community and the broader public. As part of proposed activities, the investigators will mentor a graduate student as well as two undergraduate students. One undergraduate researcher will help to develop a real-time Rossby wave break tracking tool for operational forecasters, while the second will explore the impacts of changes in Rossby wave breaking over the climate-sensitive Mediterranean region. This research will thus serve to improve our fundamental understanding of these high impact events, train the next generation of scientists in the intersectional study of weather and climate, and provide information that is of interest to members of the research community, operational forecasters, and policy/adaptation decision makers.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.