Bottom-type scattering layers and equatorial spread F

• Autores: Hysell, D. L., Chun, J., Chau Chong Shing, Jorge Luis
• Formato: artículo
• Fecha de Publicación: 2004
• Institución: Instituto Geofísico del Perú
• Repositorio: IGP-Institucional
• Lenguaje: inglés
• OAI Identifier: oai:repositorio.igp.gob.pe:20.500.12816/1827
• Enlace del recurso: http://hdl.handle.net/20.500.12816/1827; https://doi.org/10.5194/angeo-22-4061-2004
• Nivel de acceso: acceso abierto
• Materia: Ionosphere; Equatorial ionosphere; Ionospheric irregularties; Plasma waves and instabilities; http://purl.org/pe-repo/ocde/ford#1.05.01

Jicamarca radar observations of bottom-type coherent scattering layers in the post-sunset bottomside F-region ionosphere are presented and analyzed. The morphology of the primary waves seen in radar images of the layers supports the hypothesis of Kudeki and Bhattacharyya (1999) that wind-driven gradient drift instabilities are operating. In one layer event when topside spread F did not occur, irregularities were distributed uniformly in space throughout the layers. In another event when topside spread F did eventually occur, the irregularities within the pre-existing bottom-type layers were horizontally clustered, with clusters separated by about 30 km. The same horizontal periodicity was evident in the radar plumes and large-scale irregularities that emerged later in the event. We surmise that horizontal periodicity in bottom-type layer irregularity distribution is indicative of large-scale horizontal waves in the bottomside F-region that may serve as seed waves for large-scale Rayleigh Taylor instabilities.