Fig. 6From: Vertical fine structure and time evolution of plasma irregularities in the Es layer observed by a high-resolution Ca+ lidarTemporal variations of the \({{\text{Ca}}^{+}}_{\text{s}}\) layers observed just before sunrise (20:49 UT) at 100 km altitude over Tachikawa. The red vertical dotted line indicates sunrise (19:16 UT) at 100 km over a conjugate point of TachikawaBack to article page