Throughout this site, we have looked at many examples of human-influenced Climate Change. In this case, we are examining yet another form of human influence that is getting more and more notice among concerned citizens of the planet. And once again, the question arises as to whether our human influence weighs more heavily on the positive side or the negative. In this article, we are talking about human ability to create rain or modify weather, or pluviculture.
To understand pluviculture, we need to begin with Flammagenitus clouds–or fire clouds as they are commonly called. These are clouds that form as a result of forest fires, and they are characterized by high heat that rapidly ascends, carrying with it the moisture of the plants and trees that are burning. As the heat and moisture ascends and encounters cold air, the ash-filled cloud can actually create rain and extinguish the very fire that created it, provided there is enough moisture in the equation.
Native Americans and Use of Fire to Create Rain
Native Americans have a well documented history of using fire in very strategic ways, and it is reported that some had figured out the connection between forest fires and rainmaking. James Pollard Espy, meteorologist to the United States War Department, wrote in his 1840 treatise, The Philosophy of Storms, the following about the practices of indigenous peoples.
Mr. Dobrezhoffer, a missionary to Paraguay, speaking of the tall grass and bulrushes on fire, says: “I myself have seen clouds and lightning produced from the smoke, as it is flying off like a whirlwind; so that the Indians are not to blame for setting fire to the plains in order to produce rain, they have learned that the thicker smoke turns into clouds which pour forth water.”
In Espy’s 500 page work, he lays out the foundation of his case for artificial rain–a creation he insists can be “calculated with as much accuracy as that of the steam engine itself, and in part on the same principle.” His formula is based on this fundamental understanding:
I have shown by experiment, that if air at the common dew point in the summer season in time of drought, 71 degrees, should go up in a column to a height sufficient to expand it by diminished pressure into double the volume, it would condense into water or visible cloud, by the cold of expansion, more than one half of its vapor–a quantity sufficient to produce nearly three inches of rain.
Shortly afterward, in the 1800’s, several people rose to fame claiming to have a special formula that could modify the weather and cause it to rain. A few seemed to have significant results, however, most were discredited due to failure to provide the desired results.
CHINA’S WEATHER MANIPULATION EFFORT
China’s weather manipulation technology came into public awareness during the 2008 Beijing Olympics when they cleared the skies of Beijing ahead of the event, forcing the rain to come early. Currently, China invests millions of dollars in weather manipulation, which is overseen by its National Weather Modification Office. China began experimentation on such weather engineering as early as 1958 to irrigate its barren north which is marked by constant drought and famine due to sudden windstorms blasting from the Gobi desert. According to the official report, 470,000 square kilometers of land was made hail-free between 1999 and 2007. Furthermore, more than 250 billion tons of rain was created during this period. The government uses cloud-seeding techniques to produce rain for farmers, washing away heavy smog over its cities, and enabling them to hold perfect public ceremonies like the Olympics, the Asian games, World Expo and Giant Panda festival. To this end, the office employs large numbers of farmers and peasants across the country who are trained and paid to handle anti-aircraft guns and rocket launchers. These weapons are used to launch pellets containing agents (salts and minerals) into clouds. Aircraft are also used to cover larger areas. Weather engineering involves both bringing as well as stopping the rain. This process is called Cloud Seeding.
In summary, weather modification is a fascination and pursuit that human-kind has employed far longer than just the modern efforts we see in the media today. From indigenous peoples to governmental offices, it appears that we have far more influence on Climate Change than previously thought.
A Review of Cloud Seeding Experiments to Enhance Precipitation and Some New Prospects Roelof T. Bruintjes, National Center for Atmospheric Research, Boulder, Colorado, Published Online: 1 May 1999