WMOD00298

• Title: Quantifying Ice Nucleation by Silver Iodide Aerosols
• Date: 5/1/1990
• State: CO
• Weather Modification - Doc Type: Report

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6.8

6.9

6.10

6.11

6.12

6.13

6.14

6.15

6.16

6.17

6.18

6.19

6.20

Contributions to F of contact-freezing (CTF) , immersion- l52
freezing (IMF) , deposition (DEP) , and condensation-freezing
(CDF) nucleation in experiment 9588, as predicted by the
model simulation using the new ice nucleus formulations.

As in Figure 6.8, but for experiment 9188. 153

Contribution of nucleation mechanisms as formulated for 154
pure AgI in the original version of the cloud model.
Simulation is of experiment 9588. Immersion-freezing was
not formulated in the original model.

As in Figure 6.10, but for experiment 9l88. 155

Observed cumulative (+) and differential (0) fractions' 157
of ice forming versus temperature in experiment 12188 (5 m
s-l expansion), and in the equivalent model simulation
(lines).

-1
As in Figure 6.12, but for experiment 9788, a 5 m s 158
expansion seeded pre-cloud with 0.07~m AgI-AgCl aerosols.

The effect of peak supersaturation at thermodynamic cloud 159
point on cumulative ice formation by 0.03~m AgI-AgCl
aerosols. Observations are given in (a) and model results
in (b). Simulated ascent rates of 1.5 (x), 3.5 (+), and 5 m
-1
s (0) are represented (experiments 11688, 11588, 11788).

As in Figure 6.14, but for 0.07~m AgI-AgC1 aerosols. 160
Simulated ascent rates of 1.5 (x), 2.5 (0), 3.5 (+), and 5
-1
m s (0) are represented (experiments 11288, 9388, 11188,
11388).

Separation of immersion-freezing nucleation into its 161
component sources from particles collected by cloud
droplets (solid line) and those acting as CCN at cloud
formation point (dashed lines) in experiments 12188 (a) and
9588 (b).

Exactly as in Figure 6.13, but for cloud forming at -12.50C. 162

Observed (symbols) and model (lines) cumulative and 165
differential F values versus temperature in pre-cloud
seeding experiment with 0.03~m AgI-AgCl-4NaCl aerosols
(experiment 5788). Equivalent expansion updraft rate is 2.5
-1
m s .

As in Figure 6.18, but for 0.07~m aerosols (experiment 8488). 166

Model-predicted contributions of the various ice nucleation l67
modes in experiment 5788. Symbols are as used in previous
figures.

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