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Physical and statistical study of Rocky Mountain orographic clouds and precipitation and their modification: research proposal




Grant, Lewis O., author
Colorado State University, Department of Atmospheric Science, publisher

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The apparent carry-over and redistribution of artificial ice nuclei from one day to another is one of the more interesting possibilities developing from current studies related to mountain snowfall and its modification at Colorado State University. Ground released silver iodide particles in concentrations from 10 to over 500/liter are being detected consistently at mountain top levels, when released at windward ground stations at distances greater than ten miles. The Colorado State University investigations are concerned with a step-by-step investigation of the seeding process, starting with the numbers and nucleating characteristic of Ag I crystals, considering their subsequent transport and actions, and continuing to their final deposition and detection in snowfall. This is a proposal to progress the investigation of the step by-step orographic cloud processes with emphasis on investigations of actions taking place within the clouds themselves, several thousands of feet above the mountain peaks. Continuous recording instrumentation will be carried aloft by large box kites. Supporting studies of vertical transport of the ground released materials, ice nuclei numbers and activation characteristics, and snowfall velocity, mass and snow and ice crystal concentrations will be continued from the mountain observatory utilizing equipment and procedures developed under the current project. Parallel studies to detect difference in snowfall by statistical means will be continued.


Continuing research; duration: three years, beginning 1 July 1963.
Includes bibliographical references.

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Precipitation (Meteorology) -- Modification
Precipitation (Meteorology)
Orographic clouds


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