Fig. 8From: Amplitude enhancement of short period GPS-TEC oscillations over rainfall areaAverage PSD of GPS-TEC data at Phimai station. The blue and red lines indicate the PSD when we average rainfall greater than 0.04 mm/h in the area of 720 km x 720 km centered at Phimai observatory, and the green and orange lines are in the case of almost no-rain, i.e., less than 0.002 mm/h in the same area. The red and orange lines indicate the cases under geomagnetically quiet (i.e., Kp ≦ 2) condition. The upper panel show the average in 08–16LT and the lower panel shows those in 16–20LT. The error bars indicate the standard errorBack to article page