Zhang, Y., Paxton, L. J., Morrison, D., Marsh, D., & Kil, H. (2014). Storm-time behaviors of O/N₂ and NO variations. Journal Of Atmospheric And Solar-Terrestrial Physics, 114, 42-49. doi:10.1016/j.jastp.2014.04.003
Algorithms have been developed to extract net nitric oxide (NO) radiances in the wavelength range of 172-182 nm from the dayside TIMED/GUVI spectrograph data and convert them to NO column density (100-150 km). The thermospheric O/N₂ column density ratios (referenced from an altitude ~135 km with ... Show moreAlgorithms have been developed to extract net nitric oxide (NO) radiances in the wavelength range of 172-182 nm from the dayside TIMED/GUVI spectrograph data and convert them to NO column density (100-150 km). The thermospheric O/N₂ column density ratios (referenced from an altitude ~135 km with a N₂ column density of 10¹⁷ cm⁻²) are also obtained from the spectrograph data. The spatial resolution of the NO and O/N₂ products along the GUVI orbit is 240 km. The coincident O/N₂ ratio and NO column density maps during a few geomagnetic storms reveal two major features: (1) Storm-time O/N₂ depletion and NO enhancement extend from high to mid and low latitudes. They are anti-correlated on a global scale, (2) the NO enhancement covers a wider longitude and latitude region than O/N₂ depletion on a local scale. The similarity between O/N₂ depletion and NO enhancement on global scale is due to storm-time equatorward meridional wind that brings both O/N₂ depleted and NO enhanced air from high to low latitudes. The altitude dependence of the storm-time meridional wind, different peaks altitudes of the local O/N₂ and NO variations, and long life time of NO (one day or longer) may explain the different behaviors of O/N₂ and NO on a local scale. Show less