Artificial Rainfall

  The liquid water of surface evaporate by solar energy, it becomes water vapor and is flowed into the air. When the air included water vapor rises because of a rising current of air or landform like mountain, the air parcel expands adiabatically. The temperature of air parcel decreases, and it's temperature lapse rate is 0.7-1.0 °C per 100m. According to decrease of temperature, the air parcel is saturated and condensation begins on tiny impure particles called 'condensation nuclei'. And it form small cloud particle.