Applicability Analysis of IRI-2007 in Predicting TEC Over Guangzhou Region

By using GPS-TEC data observed in 2008 and IRI-TEC data derived from IRI-2007 model,the variations of Total Electron Content(TEC) are studied over Guangzhou(23.2°N,113.3°E), which is in the equatorial anomaly region.Results show that the diurnal variation of GPS-TEC shows a peak value at about 16:00 LT,while IRI-TEC is at about 15:00 LT.The seasonal variation of TEC appears a winter anomaly and semiannual pattern,maxima in equinoxes and minima in summer and winter.A good agreement is found between IRI-TEC and GPS-TEC in daytime,but a bit large deviation in nighttime,and the IRI-TEC is in more agreement with the GPS-TEC when choosing NeQuick,BO Table and URSI parameters.However,GPS-TEC shows apparent response to magnetic storm while IRI-TEC does not show any response to it.Through comparison,the applicability of IRI-2007 model in predicting TEC is analyzed over Guangzhou region,and the reasonable input options of parameters are also discussed.