Long-term changes in the dependence of <i>Nm</i>F2 on solar flux at Juliusruh

Tan Jun Rios, Maria Gloria; Borries, Claudia; Liu, Huixin; Mielich, Jens

doi:https://doi.org/10.5194/angeo-43-73-2025

Articles | Volume 43, issue 1

https://doi.org/10.5194/angeo-43-73-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Special issue:

Long-term trends in the stratosphere–mesosphere–thermosphere–ionosphere...

https://doi.org/10.5194/angeo-43-73-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 43, issue 1

Regular paper

|

21 Jan 2025

Regular paper |

| 21 Jan 2025

Long-term changes in the dependence of NmF2 on solar flux at Juliusruh

Maria Gloria Tan Jun Rios, Claudia Borries, Huixin Liu, and Jens Mielich

Data sets

Japanese solar radio flux Mark Weber https://www.iup.uni-bremen.de/gome/solar/rflux_jpn.txt

Extended Composite MgII Index V1 UVSAT https://www.iup.uni-bremen.de/gome/solar/MgII_extended.dat

Index of /download/10.5880.Kp.0001/Kp_definitive GFZ German Research Centre for Geosciences https://datapub.gfz-potsdam.de/download/10.5880.Kp.0001/Kp_definitive/

Index of /wdc/iondata/wdc_display/juliusruh/0318.00 Leibniz Institute of Atmospheric Physics (IAP) https://downloads.sws.bom.gov.au/wdc/iondata/wdc_display/juliusruh/0318.00/

Short summary

This study analyzes changes in the ionospheric response to solar flux over five complete solar cycles (1957 to 2023). We use Juliusruh hourly data of the peak electron density of the F2 layer, NmF2, and three solar extreme ultraviolet (EUV) radiation proxies. The response is better represented by a cubic regression, and F30 shows the highest correlation for describing NmF2 dependence over time. These results reveal a decrease in NmF2 influenced by the intensity of the solar activity index.