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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />The second case study from 7 February 1994 addressed the questIon of the spatial <br />distribution of supercooled cloud water over the plateau. making use of mobile radiometer data from <br />transects across the plateau, and stationary radiometer data from a location at the upwind edge of <br />the plateau. The pattern of liquid water was similar to that described previously from many cases <br />during the 1991 field program, \vith a maximum near the upwind edge, and depletion of several <br />tenths of a millimeter across the plateau. Supercooled liquid water flux estimates were compared <br />to precipitation fluxes, with the result being that the decrease in liquid across the plateau was <br />comparable to the precipitation flux values. <br />The tinal case study from 19 February 1994 involved detailed descriptions of seeding plumes <br />and the physical effects of the silver iodide seeding on this day. The plumes were clearly depicted <br />in surface and aircraft data sets, and the microphysical effects were obvious in the 2D-C probe data <br />during ten interceptions of the plume at locations 7 to 17 kIn dO\vm..ind. Ice crystal concentrations <br />in seeding plumes were enhanced by up to 25 I-i, for particles> 100llm in diameter. The ice crystal <br />plume produced a distinct radar echo plume that was observed for about 1\.VO hours. The radar plume <br />represents some of the best evidence of seeding effects to date. for a ground-based seeding <br />experiment. Precipitation measurements in the seeding plume indicated an enhancement in rate of <br />05 - 1.0 mm h-i, and an overall depth increase of up to 3 mm for the 2.25 h experiment <br />Results of trace chemical analysis of time sequential snow samples collected during the 1994 <br />field program are presented. The frequency of silver in the snow was found to be higher than in <br />earlier years when attempts were made to document the effects of valley-based seeding. The 1994 <br />data represent both valley-based and high altitude ground seeding, but in these experiments the <br />seeding generators were positioned to specifically target one location on the plateau, and this <br />positioning may have lead to the increase in success rate. <br /> <br />11l <br />