This page includes figures related to WAAS research activities in the South American region. It includes data collected obtained from the IGS network for the following stations:

Fortaleza, Brazil (3.45S latitude, 38.35W longitude, 0.23S magnetic latitude)

Brasilia, Brazil (15.57S latitude, 47.53W longitude, 10S magnetic laittude)

Kourou, French Guiana (5.08N latitude, 52.37W longitude, 9N magnetic laittude)

Note that the Kourou data clearly illustrates the post sunset enhancements in ionization. This secondary enhancement is due to the secondary peak in the equatorial electrojet. Note also that scintillation effects are not seen at either site in the August 01 data. Scintillation is not expected in this region until September.

The Brasilia figure represents ionospheric behavior in October 2000. Recent data is not available for this site. Note that the receiver at Brasilia looses lock on many nights during the 2nd enhancement in TEC.

Click on the links below to view the related figures.

1 Minute Rate of Change and ROTI

1 minute rates of change in TEC are an indicator of phase scintillation. The statistic "ROTI" is an index of phase fluctuations. It is the standard deviation of the 1 minute rates of change over a 5 minute period.

September 25, 2001 - present at Fortaleza, Brazil

September 25 -30, 2000 at Fortaleza, Brazil

October 1-31, 2000 at Fortaleza, Brazil

January 1-31,2001 at Fortaleza, Brazil

Annual Measurements

Monthly overplot of TEC data recorded from July 2000 - June 2001 at Fortaleza, Brazil

August 2001 measurements

No data available for Brazilia

TEC measurements recorded at Fortaleza, Brazil

TEC measurements recorded at Kourou, French Guiana

September 2001 measurements

TEC measurements recorded at Fortaleza, Brazil

TEC measurements recorded at Kourou, French Guiana

October 2000 measurements

TEC measurements recorded at Brasilia, Brazil (October, 2000)

TEC measurements recorded at Fortaleza, Brazil (October, 2000)

TEC measurements recorded at Kourou, French Guiana (October, 2000)