Cirrus cloud measurements have been performed during the INCA field campaigns in Punta Arenas/Chile (53.12°S, 70.88°W) and in Prestwick/Scotland (55.51°N, 4.60°W) in each hemi-spheres fall in the year 2000. From lidar backscatter profiles at 532 nm and 355 nm the optical depth (OD) of the clouds is retrieved as well as base and top altitude of the clouds, the color index and the depolarization. Cloud layers with optical depths covering more than 3 orders of magnitude have been detected by the lidar, with a high share (35%) of subvisual cirrus at both sites. Differ-ences in the results from the southern and the northern hemisphere are found in the lidar ratio and the depolarization behavior. While there is a large natural variability in cirrus properties, our results indicate a tendency towards bigger particles and columns in the southern hemisphere compared to smaller particles and small crystal plates in the northern hemisphere.