WMOD00298

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

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4.l.3 Immersion-freezing Experiments.... ...... ....... 52

4.1.4 Condensation-freezing Experiments....... ....... 55

4.1.5 Other Experiments and Experimental Summary..... 59

4.2 CLOUD MODEL SIMULATIONS..................... ......... 61

4.3 ICE NUCLEATING AEROSOLS........... ...... ............. 62

V. NUCLEATION MODE-SPECIFIC EXPERIMENTAL RESULTS...... ......... 66
5.1 DEPOSITION NUCLEATION................... .......... ... 66

5 . 1. I AgI - AgC1 Aerosols. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 66

5.1.2 AgI-AgCl-4NaCI Aerosols.. ......... ....... ...... 74
5.2 CONTACT-FREEZING NUCLEATION........ ........ ....... ... 74
5.3 IMMERSION-FREEZING NUCLEATION.... ...... ... ........... 94
5.3.1 CCN Activity of Ice Nucleus Aerosols........... 94
5.3.2 Freezing Fraction of Immersed Aerosols......... 108
5.4 CONDENSATION-FREEZING NUCLEATION..................... 119
5.4.1 Supersaturation Profiles and Residual

Computations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 119

5.4.2 AgI-AgCl Aerosols.............................. 124

5.4.3 AgI-AgCl-4NaCl Aerosols.. ............ .... ...... 131

VI. NUCLEATION BY AgI-TYPE AEROSOLS: EXPERIMENT VERSUS NUMERICAL
MODEL SIMULATIONS AND IMPLICATIONS FOR CLOUD SEEDING........ 138
6.1 GENERAL CONSIDERATIONS AND NEW ICE NUCLEUS
DESCRIPTION IMPLEMENTATION... ....... ... .... .......... l39
6.2 NUCLEATION BY AgI-AgCl AND AgI-AgCl-4NaC1 AEROSOLS:
MODEL PREDICTIONS VERSUS CLOUD CHAMBER EXPERIMENTS... l41
6.2.1 Cold Cloud Base Seeding....... ....... ....... ... 142