For the last section of my book I am currently going through the US Air force Document, Owning the Weather by 2025, with a fine tooth comb. In Chapter 4, entitled “Concept of Operations”, the authors consider the potential of a variety of different weather modification techniques. The authors describe how black carbon dust, if released into the upper atmosphere, can induce cloud cover and precipitation. I believe that the metallic particulates released during aerosol injection today are used to achieve identical results.
Here is the section from Chapter 4:
However, possibilities do exist (within the boundaries of established treaties) for using localized precipitation
modification over the short term, with limited and potentially positive results.These possibilities date back to our own previous experimentation with precipitation modification. As stated in an article appearing in the Journal of Applied Meteorology,[n]early all the weather-modification efforts over the last quarter century have been aimed at producing changes on the cloud scale through exploitation of the saturated vapor pressure difference between ice and water. This is not to be criticized but it is time we also consider the feasibility of weather-modification on other time-space scales and with other physical hypotheses.2
This study by William M. Gray, et al., investigated the hypothesis that “significant beneficial influences can be derived through judicious exploitation of the solar absorption potential of carbon black dust.”3 The study ultimately found that this technology could be used to enhance rainfall on the mesoscale, generate cirrus
clouds, and enhance cumulonimbus (thunderstorm) clouds in otherwise dry areas.
The technology can be described as follows. Just as a black tar roof easily absorbs solar energy and subsequently radiates heat during a sunny day, carbon black also readily absorbs solar energy. When dispersed in microscopic or “dust” form in the air over a large body of water, the carbon becomes hot and heats the surrounding air, thereby increasing the amount of evaporation from the body of water below. As the surrounding air heats up, parcels of air will rise and the water vapor contained in the rising air parcel will eventually condense to form clouds. Over time the cloud droplets increase in size as more and more water vapor condenses, and eventually they become too large and heavy to stay suspended and will fall as rain or other forms of precipitation.4 The study points out that this precipitation enhancement technology would work best “upwind from coastlines with onshore flow.” Lake-effect snow along the southern edge of the Great Lakes is a naturally occurring phenomenon based on similar dynamics.