WMOD00595

• Title: Lake Oroville Runoff Enhancement Project - Final Report
• Date: 9/1/1995
• Weather Modification - Doc Type: Report

2.2 Propane Dispensers

Ten propane seeding dispensers were installed along the Sierra Crest at the locations shown
on figures 2.1 and 2.3 ldl through dIm and listed in table 2.2. Liquid propane was chosen
as the seeding agent because the temperature of the cloud liquid water, as det€rmined from
mountaintop icing rate meters, was warmer than -4 "C 80 pct of the time during the winter
season. Conventional silver iodide solutions require temperatures at or below -6 oC to be
activated as ice nuclei; propane has been shown to be an effective seeding agent at
temperatures close to 0 "C tHicks and Vali, 1973).

18

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Figure 2.3. - LOREP target area showing 10Q-m contours of terrain. Location of propane dispensers are labeled d1
through dl O. precipitation gauges with three-letter identifiers. and sequential SF6 samplers .....ith a number. P2. P3. and
P6 are aircraft waypoints along the flight track used for the tracer studies.

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