EUV-TEC proxy to describe ionospheric variability using satellite-borne solar EUV measurements

[摘要] An updated version of a proxy, termed EUV-TEC, describing the global totalprimary photoionisation is calculated from satellite-borne EUV measurementsassuming a model atmosphere consisting of four major atmosphericconstituents. Regional number densities of the background atmosphere aretaken from the NRLMSISE-00 climatology. For calculation the Lambert-Beer lawis used to describe the decrease of the radiation along their way through theatmosphere. The EUV-TEC proxy thus describes the ionospheric response tosolar EUV radiation and its variability. EUV-TEC is compared against theglobal mean total electron content (TEC), a fundamental ionospheric parametercreated from vertical TEC maps derived from GPS data. Strong correlationbetween these indices is found on different time scales. Results show thatthe EUV-TEC proxy represents the ionsopheric variability better than theconventional solar index F10.7 does, especially during high and moderatesolar activity.

[学科分类] 电子、光学、磁材料