South American Regional Tracking Network

Ground receivers map

South American regional ionosphere maps (SAIM) are daily produced by GESA using La Plata Ionospheric Model (LPIM). Nearly 50 GPS ground receivers are used. The vertical total electron content (VTEC) is modeled in a solar-geomagnetic reference frame using a spheric harmonic expansion. Maps are generated for each hour. To convert slant TEC (STEC) into VTEC, a single-layer model mapping function is adopted. Results are show in two ways: Numeric grids and figures, arrange in day by day files and subdirectories. Graphical output includes three presentations: 24 hourly maps (plotted in one file), one figure composing the 24 hourly maps, and a small movie. Useful software to correctly display the movie and decompress the files can by found here. The figure below this text represents the VTEC condition for South America during the 11 of July 2005.

daily maps

For more information about LPIM you can read:

  • Brunini C., F. Azpilicueta, M. Gende, A. Aragón-Ángel, M. Hernández-Pajares, J.M. Juan and J. Sanz. "Toward a SIRGAS service for mapping the ionosphere's electron density distribution", Proceedings of the International Association of Geodesy Scientific Assembly 2009, 2010.
  • Brunini C., F. Azpilicueta. "GPS slant total electron content accuracy using the single layer model under different geomagnetic regions and ionospheric conditions" , Journal of Geodesy, DOI: 10.1007/s00190-010-0367-5, 2010.
  • Brunini C., F. Azpilicueta. " Accuracy assessment of the GPS-based slant total electron content (sTEC)", Journal of Geodesy, Springer - Verlag, DOI 10.1007/s00190-008-0296-8, 2009.
  • Brunini C., A. Meza, M. Gende, F. Azpilicueta. "South American regional maps of vertical TEC computed by GESA: a service for the ionospheric community". Advances in Space Research, Elsevier, DOI: 10.1016/j.asr.2007.08.04, 2007.
  • Conte F., F. Azpilicueta, C. Brunini, "Ground- and space-based GPS data ingestion into the NeQuick model", Journal of Geodesy, 2011.
  • Ciraolo L., F. Azpilicueta, C. Brunini, A. Meza, S. M. Radicela. "Calibration errors on experimental slant total electron content determined with GPS". Journal of Geodesy, Springer, (81) 2, 111-120, DOI: 10.1007/s00190-006-0093-1, 2007.
  • Azpilicueta F., C. Brunini y S. M. Radicella. "Global ionospheric maps from GPS observations using modip latitude". Advances in Space Research, DOI: jasr-d-04-01245, 2006.
  • Quiet and perturbed ionospheric representation according to the electron content from GPS signals Brunini C., Van Zele M.A., Meza A. and Gende M. Journal of Geophysical Research, Vol. 107, 2002.
  • A new ionosphere monitoring technology based on GPS. Brunini C., Meza A., Azpilicueta F., Van Zele M.A., Gende M. and Diaz A. Astrophysics and Space Science, Kluwer Academic Publishers, Vol. 290, 2004.

For more information contact:

GESA gratefully acknowledges all SIRGAS community. Special thanks to Juan Pablo Calderón and Eduardo Suarez.