Rainfall is the result of water vapor condensing and precipitating, forming droplets that fall from clouds due to gravity. It is an important part of the water cycle.
Condensation occurs when the air cools and becomes saturated. Clouds form when water condenses on particles in the air. The air can be cooled in several ways. Adiabatic cooling is caused by rising and expanding air. Conductive cooling occurs when air is affected by a colder surface. Radiative cooling is caused by infrared radiation, and evaporative cooling occurs when the air is saturated due to evaporation.
All of these forms of cooling can lead to the saturation of the air, condensation and precipitation. These processes may lead to the formation of clouds and water droplets, which leave the air as rainfall.Learn More
Convectional rainfall occurs when the warm air deflected from a landform rises and forms rain clouds. Convectional rainfall is very common in tropical areas as well as areas in southeastern England.Full Answer >
Orographic rainfall is rain that is produced from the lifting of moist air over a mountain. The moist air rises and cools, producing orographic clouds, which are the source of the rain. Most orographic rain falls upwind of the mountain range, with some also falling a short distance downwind. This process can produce any type of precipitation, including snow, sleet, hail or freezing drizzle.Full Answer >
The average rainfall in the Amazon rainforest is about 108 inches per year. The high amount of rain combined with a warm year-round climate makes the Amazon rainforest the most biodiverse place on Earth.Full Answer >
The Arab Republic of Egypt receives an average of 2 inches of rain a year. The amount of rain varies by region: the area along the Mediterranean Sea gets about 8 inches a year, while in the rest of the country, rain is very scarce.Full Answer >