A large amount of variation between the individual structure functions was seen in Figure 5 . Smaller scale oscillations were embedded on the individual structure functions. These oscillations show small scale variations in the cirrus features. The effects of the area averaging can be seen in the average structure function where the small scale oscillations have been smoothed out. If a vertically pointing system were used to determine the cirrus cloud structure, the result would be a single structure function defining the whole region.
More detailed explanations are in the text.
The average cross wind structure function is shown in Figure 6 . The movement of a widespread cirrus cloud deck from the northwest into a region which previously contained scattered cirrus clouds biased the structure function to larger lag distances. The average cross wind structure function shows cirrus clouds with lengths of 14 km and 43 km. The distance between cirrus clouds was 24 km. As expected, the cross wind structure function was very different than the along wind structure function during this time period.