Mesospheric gravity waves and ionospheric plasma bubbles observed during the COPEX campaign

During the Conjugate Point Experiment (COPEX) campaign performed at Boa Vista (2.80∘N;60.70∘W, dip angle  21.7∘N21.7∘N) from October to December 2002, 15 medium-scale gravity waves in the OHNIR airglow images were observed. Using a Keogram image analysis, we estimate their parameters. Most of the waves propagate to Northwest, indicating that their main sources are Southeast of Boa Vista. Quasi-simultaneous plasma bubble activities in the OI 630 nm images were observed in seven cases. The distances between the bubble depletions have a linear relationship with the wavelengths of the gravity waves observed in the mesosphere, which suggests a direct contribution of the mesospheric medium-scale gravity waves in seeding the equatorial plasma bubbles.

Research highlights
► We observe 15 medium-scale gravity waves near to the equator and calculate their parameters using the Keogram methodology.
► The waves present an anisotropy that suggests the main sources is at southeast of Boa Vista.
► A linear relationship between the distances of the plasma bubble depletions and the horizontal wavelengths of the mesospheric gravity waves is presented.
► This relationship suggests a direct contribution of the gravity waves in the seeding mechanism of the ionospheric plasma bubbles.