Causes of precipitation-Geography homework

how precipitation is caused by things such as pressure and air

1. Causes of precipitation Homework

2. Causes of precipitation- Section A 2a) precipitation in Fig 2.1 is due to convection b) In Fig 2.1 precipitation is caused convection by air being heated by the sun and expanding and rising. However, in Fig 2.2 precipitation is caused by air being forced to rise over the mountain due to winds, causing orographic (relief) rainfall. In both Figures, warm moist air is rising. Evaporation is taking place in bodies of water in both figures, although in Fig 2.1 evaporation also takes place whereas in Fig 2.2 it doesn’t. c) Frontal Precipitation happens due to the convergence of two air masses. One is usually warm and moist, while the other is cold and dry. When these masses meet they create a boundary called a front. Warm fronts occur when warm air advances and rises over the cold, which is heavier and denser. When this warm air ascends it also expands cools adiabatically (without heat exchange with its surrounding). Tiny particles in the atmosphere ( like dust, smoke or salt) provide a surface for water vapour to condense onto, causing condensation to take place. If this condensation continues there will be a growth in warm droplets which fall as rain when heavy enough along the frontal boundary. Cold fronts take place when heavy cold air advances and a body of warm lighter air is pushed under