WMOD00298

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

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LIST OF FIGURES

Number Page

3.1 Schematic diagram of the CSU dynamic cloud chamber and its 23
support systems. Various details are referred to and
discussed in the text.

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3.2 An example of a programmed (T versus P) versus the 25
simulated ascent profile experimen~ally observed (T versus
P) in the dynamic cloud chamber. Dewpoint temperature as
measured by the optical condensation-type hygrometer is
also shown.

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3.3 FSSP Cloud droplet spectra observed at various times after 26
the thermodynamic cloud point indicated in Figure 3.2.

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3.4 Plot of the shape of the unit transfer function formulated 31
for the required deconvolution of ice data (see text). Also
shown are ice crystal numbers measured versus time
following one of the instantaneous nucleation experiments
(using liquid CO in the dynamic cloud chamber) used to
define it. 2

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3.5 Temporal rates of ice crystal formation versus temperature 34
measured following instantaneous nucleation using dry ice.
Data are from experiments conducted in the CSU isothermal
cloud chamber by Morrison (1989). The solid line is the
unit transfer function used in this study.

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3.6 Example of the result of applying the deconvolution 35
procedure to real experimental data. The raw (lines) and
smoothed (- + -) numbers of crystals settling from the
cloud (per s) as a fraction of ice nucleus aerosols
injected versus temperature are shown in (a). The
deconvo1uted and smoothed-deconvo1uted signals are given in
(b) .

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3.7 Schematic diagram of the CSU isothermal cloud chamber. 38
The FSSP was temporarily mounted in the chamber to obtain
droplet size distributions. Further description is provided
in the text.

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3.8

Isothermal cloud chamber droplet spectra measured at
using the FSSP. Data are 5 minute averages. Constant
-3 -3
droplet concentrations of 2100 cm (LWC - 0.5 g m )
-3 -3
and 4300 cm (LWC 1.5 g m) are

-120C 39
cloud

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represented.

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