Ionospheric foF2 morphology and response of F2 layer height over Jicamarca during different solar epochs and comparison with IRI-2012 model

Abstract

Diurnal, seasonal and annual foF2 variability and the response of the F2-layer height over Jicamarca (11.9°S, 76.8°W, 1°N dip) during periods of low (LSA), moderate (MSA) and high (HSA) solar activities was investigated. The relative standard deviation (VR) was used for the analysis. The F2-layer critical frequency pre-noon peak increases by a factor of 2 more than the post-noon peak as the solar activity increases. The variability coefficient (VR) is lowest during the day (7-16%) for the three solar epochs; increases during nighttime (20-26%, 14-26%, and 10-20%, respectively for the LSA, MSA and HSA years); and attained highest magnitude during sunrise (21-27%, 24-27%, and 19-30%, respectively in similar order). Two major peaks were observed in VR - the pre-sunrise peak, which is higher, and the post-sunset peak. Generally, the variability increases as the solar activity decreases. Annually, VR peaks within 23-24%, 19-24% and 15-24% for the LSA, MSA, and HSA periods, respectively. The ionospheric F2-layer height rises to the higher level with increasing solar activity. The foF2 comparison results revealed that Jicamarca is well represented on the IRI-2012 model, with an improvement on the URSI option. The importance of vertical plasma drift and photochemistry in the F2-layer was emphasized. © Indian Academy of Sciences.