Fig. 5. (a)

Equinox daytime (left column, MLT = 13 h ± 2.5 h) and nighttime (right column, MLT = 1 h ± 3 h) electron temperatures from our data base (median plus upper and lower quartiles) versus latitude (INVDIP) for different altitudes (1st row: 350 ± 40 km; 2nd row: 550 ± 50 km; 3rd row: 850 ± 90 km; 4th row: 1400 ±150 km; 5th row: 2000 ± 300 km) and three levels of solar activity: (a) low PF_10.7 < 110 (dashed line with triangles), (b) medium 110 ≤ PF_10.7 ≤ 180 (dash dot line with squares), (c) high PF_10.7 > 180 (solid line with circles); N_p is total number of measurements for each curve.