Validation of ICON‐MIGHTI Thermospheric Wind Observations: 1. Nighttime Red‐Line Ground‐Based Fabry‐Perot Interferometers

• Published in: Journal of geophysical research. Space physics 2021-02, Vol.126 (2), p.n/a
• Main Authors: Makela, Jonathan J., Baughman, Matthew, Navarro, Luis A., Harding, Brian J., Englert, Christoph. R., Harlander, John M., Marr, Kenneth D., Benkhaldoun, Zouhair, Kaab, Mohamed, Immel, Thomas J.
• Format: Article
• Language: English
• Subjects: nightglow; thermospheric winds
• ISSN: 2169-9380; 2169-9402
• DOI: 10.1029/2020JA028726

Observations of the nighttime thermospheric wind from two ground‐based Fabry‐Perot Interferometers are compared to the level 2.1 and 2.2 data products from the Michelson Interferometer Global High‐resolution Thermospheric Imaging (MIGHTI) onboard National Aeronautics and Space Administration's Ionospheric Connection Explorer to assess and validate the methodology used to generate measurements of neutral thermospheric winds observed by MIGHTI. We find generally good agreement between observations approximately coincident in space and time with mean differences less than 11 m/s in magnitude and standard deviations of about 20–35 m/s. These results indicate that the independent calculations of the zero‐wind reference used by the different instruments do not contain strong systematic or physical biases, even though the observations were acquired during solar minimum conditions when the measured airglow intensity is weak. We argue that the slight differences in the estimated wind quantities between the two instrument types can be attributed to gradients in the airglow and thermospheric wind fields and the differing viewing geometries used by the instruments. Plain Language Summary This study presents a validation of observations made by two different types of instruments used to measure nighttime thermospheric neutral winds. These winds represent the motion of neutral particles in the thermosphere and studying their properties is critical to gaining a complete understanding of the dynamics of the Earth's upper atmosphere. We use observations made by two ground‐based Fabry‐Perot interferometers to validate measurements from the Michelson Interferometer for Global High‐resolution Thermospheric Imaging (MIGHTI) onboard National Aeronautics and Space Administration's recently launched Ionospheric Connection Explorer satellite. After identifying observations from the different instruments that are coincident in space and time, we show that the measurements are statistically highly correlated, thereby successfully validating the MIGHTI thermospheric wind observations. Key Points Measurements of nighttime thermospheric neutral winds made by Ionospheric Connection Explorer‐Michelson Interferometer Global High‐resolution Thermospheric Imaging agree with ground‐based Fabry‐Perot interferometer measurements to within 10 m/s The comparison validates the independent zero‐wind removal and analysis processes employed by these instruments