Long-term trends at the geomagnetic equator: Trend analysis

It is well known that ionospheric trends can have a strong geographic dependence. Moreover, several studies have documented the difficulties of analyzing trends in low and equatorial latitudes. For instance, solar proxies appear to have a different predictive power of critical plasma frequency. Furthermore, the secular variations of the geomagnetic field seem to have comparable effects on ionospheric trends as greenhouse cooling. These complexities may require a more comprehensive analysis of several ionospheric parameters and how they are related.
This work describes the assessment of various claims about long-term trends of ionospheric parameters in the equatorial region above the Jicamarca Radio Observatory (JRO). We compare the correlation of F10.7 and Mg II with foF2 values obtained from the Digital Portable Sounder, and the incoherent scatter radar (ISR) at JRO. Also, we estimate the role of secular geomagnetic field variations and greenhouse cooling on the long-term trends of various ionospheric parameters such as foF 2, hmF2, foE, hmE, h'F , and vertical plasma drifts.