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Show The following sections give examples of the use of the methodology described herein. A summary of results obtained and conclusions drawn from all case studies made is given in Section 5. O. 4. 5. 2 Case Study with Emerald Mountain Seeding Site The 1 cph pulsed seeding case of 10 February 1967 was selected for a detailed case study as an example of pulsed seeding from the Emerald Mountain generator location. 4. 5. 2. 1 Synoptic Pattern, Moisture and Stability The long wave ridge position was near the west coast, giving moist northwest flow over the area (Figure 85). 500 mb wind speeds were 65 knots at the beginning of the period, decreasing to 40 knots by the end. Lapse rates were neutral; moist air extended from 10,000 ft. MSL to 15,000 ft. MSL (cloud -l8 °C) until 0900 MST (Figures 86 and 87), and then deeptop temperature ened to 22, 000 ft. MSL (-40°C tops) by 1600 MST (Figure 88). An inversion was present between 8200 and 9200 ft. MSL on the 0344 MST Mt. Harris radiosonde (Figure 87). Precipitation totals were low and the ridge-valley precipitation ratio indicates a nearly pure orographic storm. 4. 5. 2. 2 Seeding Schedule One cycle per hour pulsed seeding was begun at 0030 MST, 10 February, and continued until 1930 MST. Seeding was done using two modified high output Skyfire Agl generators located on 8300 ft. MSL Emerald Mountain. 4. 5. 2. 3 Computed Agl Plume Trajectories and Resulting Seeded Precipitation Fallout Areas Figures 89 through 94 show the computed trajectories for the Agl plume and seeded crystals at various temperatures. Orographic vertical velocity fields used in these computations are shown in Figures 95, 96, and 97. The record of vertical profiles of wind are pictured in Figure 98. A slow veering of the wind with time gradually shifted the calculated seeding effect to the southern edge of the target area. Rabbit Ears Pass should have been located in the area of effect during almost the entire period following the breakup of the inversion near 0600 MST. Buffalo Pass was likely located north of. most if not all of the seeding effect. 4. 5. 2. 4 Precipitation Rate Signatures Figure 99a, b, c, d shows a time history of precipitation rates (optic a l snow rate sensor) at Rabbit Ears Pass and Buffalo Pass, along with comput e d 153 |