Articles | Volume 10
https://doi.org/10.5194/ars-10-259-2012
https://doi.org/10.5194/ars-10-259-2012
19 Sep 2012
 | 19 Sep 2012

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

C. Unglaub, Ch. Jacobi, G. Schmidtke, B. Nikutowski, and R. Brunner

Abstract. An updated version of a proxy, termed EUV-TEC, describing the global total primary photoionisation is calculated from satellite-borne EUV measurements assuming a model atmosphere consisting of four major atmospheric constituents. Regional number densities of the background atmosphere are taken from the NRLMSISE-00 climatology. For calculation the Lambert-Beer law is used to describe the decrease of the radiation along their way through the atmosphere. The EUV-TEC proxy thus describes the ionospheric response to solar EUV radiation and its variability. EUV-TEC is compared against the global mean total electron content (TEC), a fundamental ionospheric parameter created from vertical TEC maps derived from GPS data. Strong correlation between these indices is found on different time scales. Results show that the EUV-TEC proxy represents the ionsopheric variability better than the conventional solar index F10.7 does, especially during high and moderate solar activity.

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