This is an example of lidar measurements of contrails over a cirrus deck in Munich.

In Fig. 1, range corrected signals (@ 532 nm) are color-coded and plotted against height (above ground) between 6 km and 10 km. The time-axis (left to right) covers about 75 minutes. The color scale gives a good approximation of the extent of the cirrus cloud: yellow and red indicate the strongest returns. The contrails are clearly visible at a height of 9.3 km. They appeared in intervals of 5 minutes.

Fig. 1: Several Contrails (April 11, 2002)