Fig. 4From: Morphology and dynamics of daytime mid-latitude sporadic-E patches revealed by GPS total electron content observations in JapanHistograms showing the distributions of a elongation azimuth, b length, and c migration speed of Es patches with frontal structures observed in 2010. They are typically elongated in E-W with the median length of ~100 km b. In c, N-S components of the migration velocities are shown. They are distributed in the range of 30–100 m/s with the average of 60 m/sBack to article page