Variations of solar EUV, UV and ionospheric foF2 related to the solar rotation period

Statistical investigation of the saturation effect in the ionospheric foF2 versus sunspot, solar radio noise, and solar EUV radiation

[1] This study explores the saturation effects in the ionospheric foF2 due to sunspot number R, solar radio noise (10.7 cm) flux F10.7, and solar EUV fluxes. To locate the R, F10.7, or EUV value at which the foF2 values are saturated, a two-segmented regression model is built based on the data of the strictly rise period of the 21st solar cycle recorded by eight ionosonde stations scattering ro...

Temporal variations of the rotation rate in the solar interior

The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995–99. We find alternating latitudinal bands of faster and slower rotation which appear to move towards the equator with time — similar to the torsional oscillations seen at the solar surface. This flow pattern ...

Which solar EUV indices are best for reconstructing the solar EUV irradiance ?

Long-term variations of the upper atmosphere parameters on Rome ionosonde observations and their interpretation

This is anOp Abstract – A recently proposed self-consistent approach to the analysis of thermospheric and ionospheric long-term trends has been applied to Rome ionosonde summer noontime observations for the (1957–2015) period. This approach includes: (i) a method to extract ionospheric parameter long-term variations; (ii) a method to retrieve from observed foF1 neutral composition (O, O2, N2), ...

Solar rotation

This paper reviews current understanding of the internal rotation of the Sun. We summarise the outcome of the latest helioseismic measurements of the angular velocity profile, and review existing dynamical models of rotation in the convection zone and in the radiative zone beneath. Finally, we discuss preliminary results along a new line of investigation.