Aircraft-induced hole punch and canal clouds: Inadvertent cloud seeding

An unprecedented dataset combining in situ measurements from microphysical probes with remote sensing measurements from cloud radar and lidar operating from the National Science Foundation (NSF)/NCAR C-130 aircraft, as well as ground-based NOAA and Colorado State University (CSU) radars, is used to describe the radar/lidar properties of a hole punch cloud and channel and the ensuing ice microphysical properties and structure of the ice column that subsequently developed.

Ice particle production by commercial turboprop aircraft climbing through clouds much warmer than the regions where contrails are produced has the potential to significantly modify the cloud microphysical properties and effectively seed them under some conditions. Jet aircraft may also be producing hole punch clouds when flying through altocumulus with supercooled droplets at heights lower than their normal cruise altitudes, where contrails can form.