LAUSR

AbstractTwo-dimensional (2D) imaging probes, such as the 2D Stereo (2D-S) and Cloud Imaging Probe (CIP), are routinely used to provide in situ measurements of cloud particle properties. The basic measurement is shadow-graphs of water drops and ice particles from which particle size distributions, projected particle area and mass concentrations are determined. These data permeate data archives of domestic and foreign government agencies, universities and in the private sector. This paper provides results from laboratory tests and flight tests on a Learjet research aircraft that give new insights into the performance of the 2D imaging probes, and how their performance may have impacted measurements collected in data archives. The laboratory tests are conducted with the aid of two devices: 1) A droplet generator that provides known concentrations of water drops from about 15 to 65 μm ± 1 μm that can be positioned in the probe’s sample volume with 10-μm precision. 2) A motorized, spinning platform that suppor...