CLOUD SEEDING BY FARMERS

Prof. T.Shivaji Rao

Director, center for Environmental Studies

GITAM University

     Human society has evolved to such an extent at this activity or producing weather and climate modification to a great extent. One of the features of physical Environment that  influences human life is the most fundamental is the climate change. It is said that “Human lives”  are what the sun, the winds, and the waters make them. History tell us that when the climate conditions changed, civilizations, flourished and ultimately perished. Main fractures which determine the health and welfare of man are climate , food diseases and cultural level. Climate determines the distribution of human progress and those nations which controlled climatic conditions prospered and those that failed to manipulate climate perished in the long run.

     The condition and behavior of the air ,at a given place consequent the weather. The air, and its temperature, pressure, direction, wind vilacity, humidity, amount of cloudiness, and rainfall are the chief components of weather. They influence in human activities for the good of man  in their own way. If a man wants to progress and pros pour he must use his intelligence to manage these elements of weather to generate more forests, and more food. Weather means a state of atmosphere at a given time indicating the short term changes of atmosphere in terms of temperature, pressure,wind, moisture, clouds, rain, and visibility. It is constantly changing , sometime from our to our and at  other  times from day to day.Climate is the some total of  different  weather conditions of a given  area or a place. So it is “Average weather” . So climate is the integration of weather while weather is the differentiation of climate it is the heat  and the moisture budjet of a specified area that describes the climate. It influences the population  distribution through their influence on various economic activities including forests Agriculture, Industries and urbanization. Applied climatology makes use of climatic elements for the betterment of human life wealth and welfare.

     It is believed since long atmosphere is composed of water wvapour (60% to 70%) carbon dioxide (10% to 15%) and Nitrogen (8% to 10%) . Today the atmosphere contains the following gases.

Constituent	Per cent By volume	Constituent	Percent By volume
Nitrogen	78.08	Ozone	0.00006
Oxygen	20.94	Hydrogen	0.00005
Argon	0.93	Krypton	Trace
Carbon dioxide	0.03	Xenon	Trace
Neon	0.0018	Methane	Trace
Helium	0.00005

     Today the water vapour in the  atmosphere varies from 0.02% by volume in a cold dry climate  to about  4% in the humid tropics. 90% of water wapper is below 6 km of the atmosphere while about 1% is found about 10 km, in the atmosphere. With  increasing  height the temperature falls by 6.5 degree C per kilometer as adiabatic lapse rate.

     The earth intercepts less than a true billionth  fraction of  energy radiated by the sun. Sun provides 99.9% of the energy that heats the earth and influences the weather  and climate. The sun’s energy  is received  on earth as electromagnetic  waves and consists of visable portion of the spectrum, lying between the invisible ultraviolet and infra redrays. Solar spectrum preaching the earth surface gets converted, after absorption by the surface, from short wave to longwave energy and it is known as heat. The amount of radiant energy is constant and is estimated at above 2 gm calaried for square  centimeter per minute(2gmcl/cm square per min).