Thermospheric Estimation and CHaracterization with Nitric Oxide (TECHNO)

Michigan Technological University, Houghton MI

Investigators

Abstract

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.