WMOD00307 ‎(2)‎

• Title: Evalutation of Operational Cloud Seeding in Western Kansas - Final Report
• Date: 11/1/1987
• State: KS
• Weather Modification - Doc Type: Report

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TABLES

2.1 Counties participating in the project ............................... ~5
2.2 Bases for deployment of seeding aircraft ............................ 6
2.3 Summary of project ~rations .................................. 6
2.4 ~ing devices used m the project ................................. '7
3.1 Mean seasonal (May-August) rainfall (inches) for target and

control are,as ............................................. l~~

3.2 Double ratio results for the northwest control, the west control,
and the statistical control ..................................... 19

FIGURES

1.1 Study area for the Western Kansas Weather Modification Project .....,..... 2
2.1 Western third of Kansas, showing counties that participated in the
project and towns at which project aircraft were located .................. 4J
2.2 Di~tribution of all seeding agents, May-August 1977-85 . . . . . . . . . . . . . . . . . . 9
2.3 Distribution of silver iodide only, May-August 1977-85.................. 10
2.4 Diistribution of dry ice only, May-August 1977-85 . . . . . . . . . . . . . . . . . . . . . . . .11
3.1 Target area and northwest and west control areas . . . . . . . . . . . . . . . . . " . . . .. 12
3.2 Average May-August rainfall, 1948-1974. . . . . . . . . . . . . . . . . . . . . .. . . . .. 14
3.3 Average May-August rainfall, 1975-1985 . . . . . . . . . . . . . . . . . . . . . . '. . . . .. 1~5
3.4 Average July rainfall, 1948-1974 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3 .5 Average July rainfall, 1975-1985 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.6 Ratio of average May-August rainfall during seed years (1975-8.5) to average
May-August rainfall during no-seed years (1948-74) . . . . . . . . . . . . . . . . . . . . 20
3.7 Regions (shaded) where May-August rainfall during seed years (1975-85)
was significantly different than that during no-seed years . . . . . . . . . . . . . . . . . . . 22
3.8 Ratio of average July rainfall during seed years (1975-85) to average July
rainfall during no-seed years (1948-74) . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 23
3.9 Regions (shaded) where July rainfall during seed years was significantly
different from that during no-seed years . . . . . . . . . . . . . . . . . . . . . . . ~ . . . . .. 24
4.1 Average loss-cost ratio for the years 1948-1974 ....................... 27
4.2 Ratio of average loss-cost during seed years to average loss-cost during

no-seed years .............................................. 29
4.3 Probability that loss-cost ratios during seed years were greater than those '
during no-seed years, as calculated by the Wilcoxon rank-sum test. . . . . . . . . .. 30
4.4 Relative numbers of tall thunderstonns moving from directions &om south .
through west to north across western Kansas ...................',..... 32
45 Double ratio calculated to determine relative importance of hail as contributqr
to total precipitation during seed and no-seed years ..................... 34