Comparison of the Thermospheric Nitric Oxide Emission Observations and the GITM Simulations: Sensitivity to Solar and Geomagnetic Activities. Issue 12 (10th December 2018)

• Record Type: Journal Article
• Authors: Lin, Cissi Y.; Deng, Yue; Venkataramani, Karthik; Yonker, Justin; Bailey, Scott M.
• Is Part Of: Journal of geophysical research. Volume 123:Issue 12(2018)
• Page Start: 10, 239
• Page End: 10, 253
• Publication Date: 2018-12-10
• Subjects: nitric oxide -- metastate nitrogen -- energy budget -- thermospheric cooling; Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1029/2018JA025310
• Languages: English
• ISSNs: 2169-9380

Abstract

Abstract: An accurate estimate of the energy budget (heating and cooling) of the ionosphere and thermosphere, especially during space weather events, has been a challenge. The abundance of nitric oxide (NO), a minor species in the thermosphere, is an important component of energy balance here because its production comes from energy sources able to break the strong bond of molecular nitrogen, and infrared emissions from NO play an important role in thermospheric cooling. Recent studies have significantly improved our understanding of NO chemistry and its relationship to energy deposition in the thermospheric photochemical reactions. In this study, the chemical scheme in the Global Ionosphere‐Thermosphere Model (GITM) is updated to better predict the lower thermospheric NO responses to solar and geomagnetic activity. We investigate the sensitivity of the 5.3‐μm NO emission to F 10.7 and Ap indices by comparing the global integrated emission from GITM with an empirical proxy derived from the Sounding of the Atmosphere using Broadband Emission Radiometry measurements. GITM's total emission agrees well within ±20% of the empirical values. The updated chemistry scheme significantly elevates the level of integrated emission compared to the previous scheme. The inclusion of N2 (A)‐related production of NO contributes an additional 5–25% to the emission. Localized enhancement of ~70% in column density and a factor of 3 in column emission are simulated at a moderate geomagnetic level. Key Points: The chemistry scheme in GITM is updated with modern lab results GITM's NO global emission agrees within 20% of TCI and shows similar relationship to geophysical indicators of energy deposition Increases of 70% in column density and factor of 3 in column emission are observable during a simulated storm