Thermospheric Estimation and CHaracterization with Nitric Oxide (TECHNO)

极光通常在高纬度地区以壮观的光展示的形式出现，可以是离散的、连续的或漫射的。不同种类的极光有不同的产生机制，前者在天空中表现为“窗帘”或清晰的“带状或线条”，而后者在地面上则是“模糊”的结构。TECHNO（用一氧化氮估算和表征热层）旨在改进极光的建模，并详细探测磁暴期间高层大气环流的反应。该方法包括在全球电离层-热层模型（GITM）模型中纳入与离散极光相关的物理和化学，因为它目前仅限于漫射极光。TECHNO将通过观察大气中的关键化学成分一氧化氮（NO）的季节性变化，以及它与极光和极地涡旋的变化之间的关系，来研究磁暴期间高层大气环流的变化。研究这些问题对于改善直接影响高频无线电通信和GPS/GNSS卫星导航的极光预报，以及影响近地轨道卫星和空间碎片轨道的高层大气密度变化至关重要。这项跨学科的工作促进了科学知识的发展，并将支持对早期职业科学家的培训。NO在热层的总体热收支中起着重要作用，因为它通过红外发射在辐射冷却中发挥作用。因此，它是控制电离层-热层系统中能量和动量分布的过程之一。其他因素包括：(a)粒子降水增加时离散极光的增强和(b)由于压力梯度增加而引起的经向风的增强。主要目的是研究极地涡旋变率和离散极光对NO浓度的影响。第二个目标是量化与NO相关的温度和密度的模型不确定性。该方法包括使用各种电离层模型（GITM， MAGNIT），使用GITM模拟风暴，使用卫星数据集进行验证。该项目最后将研究极光能量的不确定性和向下通量的增加如何影响由此产生的中性密度和温度的变化。这项研究与GEM和CEDAR项目的相关性将加强这两个科学界之间的合作。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。

Auroras appear in the form of spectacular light displays usually at high latitudes and can occur either as discreet, continuous, or diffuse varieties. The different kinds of auroras have different generation mechanisms with the discreet appearing as “curtains” or well defined “ribbons or lines” in the sky, while the latter are visible as “fuzzy” structures from the ground. TECHNO (Thermospheric Estimation and Characterization with Nitric Oxide) aims at improving the modeling of aurora and probing in detail how the circulation in the upper atmosphere responds during magnetic storms. The methodology involves incorporating the physics and chemistry associated with discrete aurora in the Global Ionosphere-Thermosphere Model (GITM) model, as it currently is limited to diffuse aurora. TECHNO will investigate how the circulation of the upper atmosphere changes during magnetic storms by looking at how key chemical components of the atmosphere, Nitric Oxide (NO) varies seasonally and how it is related to changes in the aurora and the polar vortex. Investigating these issues is crucial to improving forecasts of the aurora that directly impact HF radio communication and GPS/GNSS satellite navigation, as well as changes in the density of the upper atmosphere that affect the orbits of satellites and space debris in Low Earth Orbit. This inter-disciplinary work advances scientific knowledge and will support training of an early-career scientist.NO plays a significant role in the overall heat budget of the thermosphere due to its role in radiative cooling via infrared emissions. Thus, it is one of the processes that govern the distribution of energy and momentum in the ionosphere-thermosphere system. The other factors include intensification of (a) discreet aurora during increased particle precipitation and (b) meridional winds due to increased pressure gradients. The main objective of the work is to investigate the changes in NO concentrations caused by the polar vortex variability and discreet aurora. The second goal is to quantify the model uncertainties in temperature and densities as it relates to NO. The methodology comprises use of various ionospheric models (GITM, MAGNIT), simulations of storms using GITM, validation with the satellite data sets. The project will conclude with a study of how the uncertainties in auroral energy and increased downward flux affect variations in the resulting neutral density and temperature. Relevance of this research to both GEM and CEDAR programs will enhance collaborations between these two scientific communities.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.