A comparison of ionosonde measured foF2 and IRI-2016 predictions over China

Abstract A comparison of the ionospheric F-region critical frequency (foF2) between ionosonde measurements and IRI-2016 predictions is studied over China during the period from January 2008 to October 2016. Four stations are selected, and the latitude coverage starts at 49.4°N and ends at 23.2°N with a sequential latitude interval of about 10°, the corresponding geomagnetic latitudes are from 39.5°N to 13.2°N. The results show that the variability of the observed foF2 versus latitudes, seasons, local time and levels of solar activity could be well reproduced by IRI-2016. However, the daily lowest value of foF2 from the IRI-2016 prediction occurs earlier than that from the ionosonde. Around the sunrise, the IRI-2016 prediction shows a very sharp rise and grows much faster than the observed foF2 in every month. The foF2 difference between the two options (URSI and CCIR) in IRI-2016 increases as the F10.7 index decreases. During 2008–2009, the annual average deviations of URSI and CCIR range from −5% to −10% and from 5% to −5%, respectively. Generally, the CCIR performs better than URSI during postsunset under low solar activity or in Equatorial Ionization Anomaly (EIA) region over China, while it shows no large difference in performance with URSI in other locations or for other time.

[1]  R. Y. Liu,et al.  A new solar index which leads to improved foF2 predictions using the CCIR Atlas. , 1983 .

[2]  Reinhart Leitinger,et al.  Topside electron density in IRI and NeQuick: Features and limitations , 2006 .

[3]  Łukasz Tomasik,et al.  The 2009–2012 Ionosonde and IRI2012 Variability of foF2, hmF2, M3000F2, B0, B1 Parameters over Warsaw , 2016, Acta Geophysica.

[4]  H. Rishbeth,et al.  Annual and semiannual variations in the ionospheric F2-layer: II. Physical discussion , 2000 .

[5]  Bruno Zolesi,et al.  Behaviour of ionospheric magnitudes of F2 region over Tucumán during a deep solar minimum and comparison with the IRI 2012 model predictions , 2014 .

[6]  Y. Kuo,et al.  Ionosphere equatorial ionization anomaly observed by GPS radio occultations during 2006-2014 , 2015 .

[7]  H. Lühr,et al.  IRI‐2007 model overestimates electron density during the 23/24 solar minimum , 2010 .

[8]  J. Adeniyi,et al.  Monthly mean foF2 model for an African low-latitude station and comparison with IRI , 2014 .

[9]  Hanlu Zhang,et al.  Ionospheric disturbances on 8 September, 2010: Was it connected with the incoming moderate Chongqing earthquake? , 2012 .

[10]  T. Maruyama,et al.  Comparison of ionosphere characteristic parameters obtained by ionosonde with IRI-2007 model over Southeast Asia , 2013 .

[11]  Yang Li,et al.  Extended Analysis of Real‐Time foF2 Mapping in Mideastern China Based On Shortwave Signals , 2017 .

[12]  T. Maruyama,et al.  Ionospheric variation at Thailand equatorial latitude station: Comparison between observations and IRI-2001 model predictions , 2010 .

[13]  Pornchai Supnithi,et al.  A comparison of neural network-based predictions of foF2 with the IRI-2012 model at conjugate points in Southeast Asia , 2017 .

[14]  Edward W. Cliver,et al.  Revisiting the Sunspot Number , 2014, 1407.3231.

[15]  T. Yokoyama,et al.  Temporal change of EIA asymmetry revealed by a beacon receiver network in Southeast Asia , 2015, Earth, Planets and Space.

[16]  Libo Liu,et al.  Solar activity variations of nighttime ionospheric peak electron density , 2006 .

[17]  S. J. Adebiyi,et al.  Ionospheric foF2 morphology and response of F2 layer height over Jicamarca during different solar epochs and comparison with IRI-2012 model , 2014, Journal of Earth System Science.

[18]  A. Yoshikawa,et al.  NmF2 and hmF2 measurements at 95° E and 127° E around the EIA northern crest during 2010–2014 , 2015, Earth, Planets and Space.

[19]  I. Batista,et al.  Ionospheric variability at Brazilian low and equatorial latitudes: comparison between observations and IRI model , 2004 .

[20]  R Liu,et al.  A CORRECTED METHOD OF THE INTERNATIONAL REFERENCE IONOSPHERE TO BE USED IN GHINESE REGION , 1994 .

[21]  D. Bilitza,et al.  Measurements and IRI model predictions during the recent solar minimum , 2011, 2011 XXXth URSI General Assembly and Scientific Symposium.

[22]  Shunrong Zhang,et al.  Comparative study of ionospheric characteristic parameters obtained by DPS-4 digisonde with IRI2000 for low latitude station in China , 2002 .

[23]  Bodo W. Reinisch,et al.  International Reference Ionosphere 2016: From ionospheric climate to real‐time weather predictions , 2017 .

[24]  D. Bilitza,et al.  EQUATORIAL F2-PEAK PARAMETERS,IN THE IRI MODEL , 2003 .

[25]  Jiankui Shi,et al.  Ionospheric behavior of the F2 peak parameters foF2 and hmF2 at Hainan and comparisons with IRI model predictions , 2007 .

[26]  C. Rush.  URSI foF2 model maps (1988) , 1992 .

[27]  Zhensen Wu,et al.  Diurnal specification of the ionospheric f0F2 parameter using a support vector machine , 2010 .

[28]  O. S. Poltavsky,et al.  Evaluation of the IRI model for the European region , 2009 .

[29]  T. Maruyama,et al.  Thailand low and equatorial F2-layer peak electron density and comparison with IRI-2007 model , 2012, Earth, Planets and Space.

[30]  F. Chishtie,et al.  Variation of hmF2 and NmF2 deduced from DPS-4 over Multan (Pakistan) and their comparisons with IRI-2012 & IRI-2016 during the deep solar minimum between cycles 23 & 24 , 2018 .

[31]  Li-xin Guo,et al.  Spread-F occurrences and relationships with foF2 and h′F at low- and mid-latitudes in China , 2018, Earth, Planets and Space.

[32]  P. Fagundes,et al.  Equatorial F2-layer variations: Comparison between F2 peak parameters at Ouagadougou with the IRI-2007 model , 2012, Earth, Planets and Space.