WMOD00372

• Project Name: High Plains Cooperative Program
• Title: The Design of HIPLEX-1
• Date: 4/1/1979
• Weather Modification - Doc Type: Report

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in liquid water concentration. The ice crystals produced by seeding
have significant advantage over those that occur in unseeded clouds
because they ori~lnati earlier ln the lifetime of the cloud. This
leads to the ear ier (~pearance of precipitatlng ice partlcles in
the seeded clouds, so that greater concentrations and larger sizes
of such particles are present at comparable times after treatment.

~.

4. Radar first echoes develop earlier in seeded clouds than in
un seeded clouds.

5. Precipitation falls from cloud base in the form of graupel
and/or rain (melted graupel) earlier in the lifetime of the seeded
cloud and in greater volume than occurs in unseeded clouds. In
addition, a larger proportion of seeded clouds than unseeded
clouds will produce rain.

6. Rain at the ground, averaged per experimental unit, is greater
for seeded clouds than for unseeded clouds.

Appendix B contains a more detailed discussion of conceptual models.

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