Document Type : Research Paper
Author
Master of Natural Geography
Abstract
Controlling and utilizing atmospheric phenomena and changes such as creating artificial rain in dry years and droughts, preventing harmful hail and haze and reducing the severity of storms has been among human desires since immemorial past.
In the last half century, the technology of cloud insemination has created hopes for realization of these dreams.
Early research for stimulating clouds and creating artificial rain has been carried out by Wegner in Germany, Vilkevitch in the former Soviet Union and Veraart in the Netherlands. The production of artificial rain was gradually considered by other countries, and in 1933 T. Bergeron identified ice crystals and very cold droplets as among the main causes of rain, and many subsequent studies were carried out. Cloud fertilizing and artificial rain production has been tested in many countries of the world, and this technology has been considered as a way of water preparation in many countries, especially those facing water crisis, and each year fertility operations are carried out in these countries in appropriate seasons and according to a regular program, and at the end of the project the operation is evaluated and the efficiency of precipitation increase is calculated using statistical and mathematical methods. In addition, further research on atmospheric systems, cloud physics, cloud behavior, economic and social significance of massive insemination of clouds and formation of rain, various chemicals used for injections in the clouds, methods of carrying out the work, recognition of appropriate climatic conditions, implementation of cloud fertilizing operation and increase of efficiency of operations are also in line with the objectives of the studies.