The Study of Temporal Variations in Ionosonde foF2 and GPS TEC at Multan and Islamabad during Low and High Solar Activity in Solar Cycle 24

Abstract

The study of temporal variations in critical frequency of the F2 layer (foF2) and total electron content (TEC) calculated from satellites of GPS (Global Positioning System) has been conducted at Multan (Geog. Lat: 30.16°N, long: 71.53°E) and Islamabad (33.66°N, 73.23°E) during low solar activity (LSA) year 2009 and relatively high solar activity (HSA) year 2012 of solar cycle (SC) 24. In general, it has been observed that the diurnal variations show peak values around post noon hour 1500 LT. The winter anomaly is completely absent during LSA year 2009. The semi-annual variations show dependency on the state of solar cycle. The foF2 and GPS TEC observed values are greater in HSA as compared to LSA indicating the major contribution of sunspot activity in the ionization of ionosphere. The observed values of foF2 and GPS TEC have been compared with the latest version of International Reference Ionosphere (IRI-2016) model. It has been found that Root Mean Square Error (RMSE) shows larger values in IRI TEC as compared to foF2. The lowest RMSE in foF2 and TEC are 0.40 and 1.66 at Multan while the same are 0.30 and 1.06 at Islamabad. In general, most of the time, error in predicting foF2 and TEC is large at Multan as compared to Islamabad.

Keywords: TEC, IRI, GPS, foF2, LSA, HSA

Cite this Article

Muhammad Atiq, Naeem Sadiq. The Study of Temporal Variations in Ionosonde foF2 and GPS TEC at Multan and Islamabad during Low and High Solar Activity in Solar Cycle 24. Research & Reviews: Journal of Space Science & Technology. 2018; 7(2): 8–17p.