WMOD00285 ‎(2)‎

• Title: Feasibility Study of Wintertime Cloud Seeding to Augment Arizona Water Supplies
• Date: 1/1/1987
• State: AZ
• Weather Modification - Doc Type: Report

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Figure 1. - Illustration of the cloud conditions giving rise to optimum
seeding potential. Seeding strategy is to take advantage of liquid
water through addition of more ice to lowl~r crystal trajectories, sweep
out the liquid, and minimize loss of both liquid and ice escaping the
barrier (from Reynolds and Dennis, 1986).

condensation of moisture as the moist air is forced to rise over high
terrain. The basic characteristics of this cloud include the following
(Grant and Rauber, 1985):

1. Vertical extent of up to several kilometers with the cloud base
frequently below mountain crest elevation.

2. Often stably stratified but may be neutral or possess small
pockets with weak instability.

3. Horizontal dimensions varying with barrier size, moisture pre-
sence and orthogonal windspeed.

4. Precipitation efficiency,.mostly dependent on temperature,
orthogonal windspeed, up-barrier horizontal extent of cloud,
secondary ice production potential and barrier slope.

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