Intercomparison of total electron content maps for the South American region

GENDE M.; BRUNINI C.; MEZA A.

Perugia

Congreso; IUGG XXIV General Assembly; 2007

International Union of Geodesy and Geophysics

Since July 2005 Vertical Total Electron Content (VTEC) hourly maps have been generated for the SouthAmerican region. Thesemapsweremodeledusing a lineal combination of GPS carrier phase observables. Different research centers (JPL, CODE, UPC, ESA) also compute VTEC maps using GPS permanentlytracking network but each of themobtain its results using different observables (undifferenced or double difference- carrier phase and code data), different ionosphericassumptions (single layer or tridimensional models), handling hardware-related biases in diverse ways and approaching the problem with different mathematicalfunctions (spherical harmonics, local polynomials, kriging, globalGauss-Type Exponential). Thiswork presents an inter comparison of our regionalmaps with respect tofourGlobal IonosphericMaps (GIM) for SouthAmerica in the space-time domain.Comparisons differentiate solstice and equinox seasons, lowand middle latitudes andfour different representative times of the day.