WMOD00287

• Title: The National Weather Modification Plan
• Prepared For: CAO Subcommittee on Weather Modification
• Prepared By: The Working Group of the CAO Subcommittee on Weather Modification
• Date: 2/13/1981
• Weather Modification - Doc Type: Report

o Studies to provide essential information on economic costs and
benefits and the environmental impact of weather modification
projects, to explore the institutional and legal framework for
modifying the weather, and to assess the societal responses to
operational programs.

The ~portance of the first two thrusts--fundamental research and
precipitation enhancement, espeCially for agricultural use--were particularly
noted.

C. APPROACH

The National Weather Modification Program is based on two general
assumptions: first. that modification of certain weather phenomena is
scientifically possible and second that, if it is done reliably and with
predictable results, society could benefit substantially. Determining the
validity of these assumptions and developing a reliable and acceptable
technology are the principal tasks for the research program.

There are strong relationships between weather modification and weather
forecasting. For example, improved short-term forecasting is a requirement
for meaningful weather modification. Prediction of the future weather
determines the need for modification and aids in selecting the technique and
application most appropriate for the situation. Accurate prediction of
natural events is also ~portant for detecting and evaluating the changes
brought about by the modification technique used. Conversely, knowledge
gained concerning the behavior of clouds and cloud systems through the. efforts
of the weather modification program can contribute significantly to the
science of weather prediction. For these reasons, weather modification
research must interact strongly with weather prediction research programs.

The national program proposed herein attempts to achieve the desired mL~
of theory, laboratory studies, numerical modeling, and field measurements and
experimentation through ~~o principal approaches--fundamental research and
site-specific studies.

Fundamental research consists of studies aimed at advancing our
understanding of elemental processes basic to many weather modification
objectives. These processes include the origin and growth of ice in natural
clouds, interactions, between cloud microphysics and cloud dynamics, and
interactions among clouds and be~~een clouds and their environment. This
approach also includes (1) research and development to improve instrumentation
and facilities needed for key measurements that are fundamental to the overall
objectives of weather modification research, (2) research on weather
modification methods other than cloud seeding, and (3) portions of the
research on the general societal implications of weather modification.

Site-specific studies are aimed at specific weather modification
techniques and often involve field a~perimentation to develop solutions to
localized or regional weather-related problems, such as inadequate water
supplies in the Southwest or lack of rainfall during the growing season in the

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