Seasonal and QBO variations in the OH nightglow emission observed by TIMED/SABER

摘要

Using TIMED/SABER observations, we present global distribution of the semiannual oscillation (SAO), annual oscillation (AO), and quasi-biennial oscillation (QBO) in the OH nightglow peak emission rate and height as well as the intensity. The latitudinal variations of the SAO, AO, and QBO in the peak emission rate are similar to those in the intensity. For the peak emission rate and the intensity, the SAO and QBO amplitudes have three peaks (one at the equator and others at about 35S and 35N). The AO amplitude peaks at about 20S and 20N, respectively. The SAO phase is delayed poleward from the equinoxes at the equator to the solstices at 50S/N; in addition, the phases of the AO are delayed poleward from 30S. For the peak height, the SAO and QBO amplitudes have three peaks (around the equator, 40S, and 40N). Its AO amplitudes at 50S and 50N are larger than those at other latitudes; the phase of the SAO shifts from the solstice at the equator to near the equinoxes at 50S/N. The airglow QBO is stronger in tropics than midlatitude and is likely the real QBO oscillation at the equator. In addition, the emission in the Southern Hemisphere is weaker than that in the Northern Hemisphere. The SAO and QBO are hemispherically symmetrical, and the AO is hemispherically antisymmetrical at some latitudes. The peak emission rate and peak height SAOs are generally in antiphase. The peak emission rate and intensity SAOs are generally in phase.