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Show was higher in the first pul se. Daisy 39 - 27 January 1967: This case is in comple te contrast to the previoi one. It is presented to illustrate what happens to a plume released from Ern erald Mountain in fairly stable conditions. The thermal stratification is shown in Figure 3 9. The Mt. Harris radiosonde shows a stable thermal stru ture but with no prominent inversion. The aircraft sounding taken · at the corn pletion of the run shows an inversion at 1 O, 000 ft. MSL. The zinc sulfide tracer release was pulsed at one cycle per hour, with zinc sulfide released from 1415 to 1445 MST and 1515 to 1545 MST. The mean release site wind was 033 degrees at 3. 7 mph, and was unrelated to the higher level plume vector and the upper level winds. At 8, 500 ft. MSL, when circling the release site, material was found to the south-southwest (in agreement with the mean release site wind) only out to a distance of 0. 3 miles. Evidently, the plume was caught in a very local circulation and the direction of plume travel was reversed within 1 / 2. mile from the release site. At higher levels the plume was located to the east in agreement with upper level winds. Figurd also shows a typical plume trace; it indicates a plume width of about 1 nautic mile at a distance ·of three nautical miles from the release site. Figure 40 gives the envelope of peak tracer concentration with time. Althoui the release was made in two one-half hour pulses, there is absolutely no evi· dence of pulsing here. There are significantly higher peak concentrations on several tracks but no evidence of pulsing at all. The termination of the final pulse was at 1545 MST and one hour later, when spiralling around the releas site in a one mile diameter circle, strong concentrations of tracer were still found within 1 / 2 mile of the release point. If we assume transport with the mean release site wind of 3. 7 mph there should not have been any material left, even at one mile, a full hour after termination of release. Thus, a li~ and variable wind structure probably prevailed in the stable layers near the surface, keeping some material confined to near the release site for a long period of time. Daisy 6 - 25 March 1965: The tracer signals from three tracks for this tesl are shown in Figure 41. These three tracks were at 9, 500, 10, 500 and 11, 500 ft. MSL at a distance of 3 n. mi. from the release site. At this dis· tance the plume was approximately three miles wide. It is very significant, here, that tracer was found in significant quantities at 11, 500 ft. MSL within three miles of the release point after release at 8, 200 ft. MSL. Daisy 46 - 3 April 1967: This particular release was from the radar site al Mt. Harris at an elevation of 7, 400 ft. MSL. Figure 42 shows a series of tracks 2. 5 n. mi. from the release site. The radiosonde taken at Mt. · Harri for this test showed essentially neutral conditions to 20, 000 ft. MSL. Over the Park Range Ridge, some 21 nautical miles from the release site, counts went to 2. 5 per liter above a background of 0. 2 per liter. 70 |
