Fig. 8From: Polynomial modelling of CHAMP satellite data to investigate rapid secular variation fluctuations over southern Africa during 2003 and 2004The plots of the comparison of PolyM with CHAOS-2 at two selected points (at 400 km altitude just above HER and TSU) for years 2001–2005. The annual secular variation in X, Y and Z components were calculated using the monthly main field models of January and December based on CHAMP satellite data at 400 km altitude.Back to article page