The hydrological cycle

Water doesnt leave the planet - it is continuoulsy cycled between the ocean and the atmosphere. 

Forms of precipitation

• rain
• snow
• fog
• hail

A rivers drainage basin is the area surrounding the river where the rain is failling on the land flows into the river.

The boundary of the drainage basin are called watersheds-water falling beyond the watershed enters a different drainage basin.

Drainage basins are open systems with inputs and outputs.

Water enters the system though precipitaion - leaves via evaporation, transpiration and river discharge. 

Inputs 

• Precipiation- the way moisture comes out of the atmosphere, eg, rain, hail, snow, fog.

Storage

• Interception - when some of the precipitaion lands on vegetation or other structures such as buildings, before it reaches the soil. Interception is only TEMPORARY as the water is evaporated.
• Vegetation storage - water that has been taken up by the plants.
• Surface storage - water in puddles, lakes and ponds.
• Groundwater storage- water stored in the ground, either in soil or rocks. 
• The water table - the top surface of the zone of saturation.
• Channel storage - water held in a river or channel.