Long Term Trends of the critical frequency of the F2 layer at Northern and Southern high latitude regions

• Main Authors: Alfonsi, Lu., De Franceschi, G., Perrone, L., Materassi, M.
• Other Authors: Alfonsi, Lu.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, De Franceschi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Perrone, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Materassi, M.; CNR-ISC, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, CNR-ISC
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2002
• Subjects: long term trends; 01. Atmosphere::01.02. Ionosphere::01.02.04. Plasma Physics; 01. Atmosphere::01.02. Ionosphere::01.02.05. Wave propagation; Antarctic; Antarc*
• Online Access: http://hdl.handle.net/2122/3498

Abstract The long-term behaviour of the plasma frequency of the F2 layer, foF2, is investigated to contribute to the discussion about the natural or anthropogenic origin of the ionospheric long-term changes. In this paper, long time series of hourly foF2 data from two high latitude ionospheric observatories of both the hemispheres are analysed. A decreasing trend of foF2 is found confirming a previous result obtained by using the foF2 monthly medians from Antarctic stations. This negative trend does not show a clear dependence on the long-term behaviour of the geomagnetic activity impact on the ionosphere. Published 607-612 3.9. Fisica della magnetosfera, ionosfera e meteorologia spaziale JCR Journal reserved