World rainfall patterns
World precipitation patterns are affected by atmospheric circulation, seasonal variations and spatial differences such as mountain barriers and ocean currents. Moisture is important in the transfer of heat in the atmosphere.
Water droplets form when cooling air reaches its DEW-POINT TEMPERATURE and water vapour condenses into water droplets and forms clouds. Dew-point temperature is typically 4 degrees.
The height at which rising air reaches its dew-point is the CONDENSATION LEVEL. When water droplets are large enough and heavy enough they will fall as they overcome the rising currents beneath. The droplets grow in size as they collide with others in the turbulent air.
Warm Ocean currents can increase the temperature of surrounding air masses increasing their ability to retain moisture and so increases the precipitation over the land. Cold ocean currents cause condensation and causes air to loose moisture moving across them increasing rainfall over the ocean.
Bergeron Process or cold-rain process is a process where ice crystal grow in mixed phase clouds which contain a mix of super cooled water and ice. There is rapid evaporation of liquid water and rapid ice crystal growth, when they are large enough the ice crystals fall through the cloud. If the temperature lowers the crystals will melt to rain drops as they fall to earth. .
Water droplets form when cooling air reaches its DEW-POINT TEMPERATURE and water vapour condenses into water droplets and forms clouds. Dew-point temperature is typically 4 degrees.
The height at which rising air reaches its dew-point is the CONDENSATION LEVEL. When water droplets are large enough and heavy enough they will fall as they overcome the rising currents beneath. The droplets grow in size as they collide with others in the turbulent air.
Warm Ocean currents can increase the temperature of surrounding air masses increasing their ability to retain moisture and so increases the precipitation over the land. Cold ocean currents cause condensation and causes air to loose moisture moving across them increasing rainfall over the ocean.
Bergeron Process or cold-rain process is a process where ice crystal grow in mixed phase clouds which contain a mix of super cooled water and ice. There is rapid evaporation of liquid water and rapid ice crystal growth, when they are large enough the ice crystals fall through the cloud. If the temperature lowers the crystals will melt to rain drops as they fall to earth. .
Precipitation formation
The following video summarises the processes of: Collision, Coalescence, Bergeron process and Vertical temperature stability: Rain, Freezing Rain, Sleet and Snow.