water cycle

• hydrosphere has the largest store of saline water
• less than 3% of earths water is freshwater
• majority of earths freshwater is stored in the cryosphere as glaciers
• global hydrological cycle is a closed system with no inputs or outputs
• Condensation:

  1. water vapour changes state to a liquid when it reaches its dew point
  2. water droplets can stay in the atmosphere or flow to other subsystems e.g. form due on leaves. decreases the amount of water stored in the atmosphere
  3. magnitude of condensation flow depends on the temperature and volume of water vapour in the atmosphere
• Cloud formation and precipitation:

  1. precipitation is main flow of water from the atmosphere to the ground
  2. clouds form when water vapour cools and condenses forming water droplets which gather to form clouds. When they cool they fall to the ground
  3. several things that cause the air to warm: convection, topography and other air masses
  4. cloud condensation nuclei are other particles that help water droplets condense
  5. varies seasonally