Thermospheric Estimation and CHaracterization with Nitric Oxide (TECHNO)

极光通常以壮观的灯光形式出现在高纬度地区，可以以谨慎、连续或扩散的形式出现。不同种类的极光有不同的产生机制，谨慎的极光在天空中看起来像“窗帘”或清晰的“丝带或线条”，而后者在地面上看起来像是“模糊的”结构。TECO(一氧化氮热层估计和表征)旨在改进极光的模拟，并详细探测磁暴期间高层大气环流如何作出反应。该方法涉及将与离散极光有关的物理和化学纳入全球电离层-热层模型(GITM)模型，因为它目前仅限于漫射极光。TECHNO将通过观察大气的关键化学成分一氧化氮(NO)如何季节性变化，以及它与极光和极涡的变化之间的关系，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进对直接影响高频无线电通信和全球定位系统/全球导航卫星系统卫星导航的极光的预报，以及对影响卫星轨道和低地球轨道空间碎片的高层大气密度的变化至关重要。这项跨学科的工作促进了科学知识的发展，并将支持对职业生涯早期科学家的培训。由于NO在通过红外发射进行辐射冷却方面的作用，它在热层的总体热量收支中扮演着重要的角色。因此，它是支配电离层-热层系统中能量和动量分布的过程之一。其他因素包括：(A)在粒子降水增加期间出现谨慎的极光；(B)由于气压梯度增加而产生的经向风。这项工作的主要目的是研究极涡变化和极光引起的NO浓度的变化。第二个目标是量化温度和密度的模型不确定性，因为它与NO有关。该方法包括使用各种电离层模型(GITM、MAGNIT)、使用GITM模拟风暴、利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计划的相关性将加强这两个科学界之间的合作。这一奖项反映了NSF的法定使命，并通过使用基金会的智力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.