During one leg of the second flight on this day, the UND Citation flew west southwest from the CART site in a mixed phase cloud out about 50 km, and returned along the same path. The air temperature was about -12 C and the altitude was about 6.3 km. We encountered an interesting mixed phase cloud that had very pristine looking hexagonal plates (see PMS 2DC images) mixed in with very small water droplets. Below are data from the FSSP that describe the water droplet concentration and mean diameter, data from the PMS 2DC that describe ice crystal concentration and mean diameter, and data from the King liquid water content probe that measures the total liquid water content. Note the small droplet sizes and concentration that gave quite low liquid water content. Figure 5 shows the PMS 2DC size, area, and mass distributions for this interval. The larger particles dominate these distributions.{Return}
FIGURE 1. Overlay of FSSP and PMS 2DC mean diameters for water droplets and ice crystals, respectively.
Figure 2. Concentration of water droplets (FSSP) and ice crystals (2D-C).
Figure 3. Total concentration and mean diameter of ice phase as determined from the PMS 2DC.
Figure 4. Total concentration of water droplets (FSSP), and liquid water content from the King probe.
Figure 5. PMS 2DC size, area, and mass distributions. Note that the larger particles dominate the area (radiative) and mass distributions. Average values include the concentration 0.743 / Li, the solar extinction coefficient 0.095 / km, the mead diameter 300 µm, and the estimated ice water content 3.83 mg/m3. The average true air speed of the Citation was 118.3 m/s.
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