WMOD00298

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

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TABLE OF CONTENTS

I . INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 BACKGROUND............... . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

l.2 OBJECTIVES OF RESEARCH...... ........... .............. 4
1 . 3 GENERAL APPROACH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 EXPECTED UTILITY OF RESULTS.. ........ ...... .......... 8

I I . BASIS FOR RESEARCH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lO

2.1 STATUS OF EXPERIMENTAL KNOWLEDGE OF ICE NUCLEI

FUNCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lO

2.2 DESCRIPTIONS OF ICE NUCLEI FUNCTION IN CLOUD MODELS.. 15
2.3 ICE NUCLEI FUNCTION IN REAL CLOUDS..... .... .......... 18

III. THE CLOUD CHAMBER FACILITY..... ........ .... .... ...... ....... 22
3.1 DYNAMIC CLOUD CHAMBER................................ 22
3.2 ISOTHERMAL CLOUD CHAMBER........... ..... ............. 37
3.4 AEROSOL GENERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 4l

IV. EXPERIMENTAL DESIGN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 43

4.1 LABORATORY EXPERIMENTS................. .... ..... ..... 47

4.1.1 Deposition Nucleation Experiments.... ..... ..... 47

4.1.2 Contact-freezing Nucleation Experiments........ 49

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