5.2a

• what are the flows in the hydrological cycle?

  interception

  infiltration

  direct runoff

  saturated overland flow

  throughflow

  percolation

  groundwater flow
• interception?

  water landing on vegetation or other surfaces like buildings or concrete surfaces before reaching the soil
• infiltration?

  water soaking into the soil
• direct runoff?

  water flowing over the land. it happens because rain is falling on the ground faster than infiltration can occur
• saturated overland flow?

  water flowing over the land because the soil is saturated so no longer has the capacity to allow any more water to infiltrate
• throughflow?

  water flowing slowly downhill through the soil due to gravity
• percolation?

  water seeping vertically, further through soil into the water table
• groundwater flow?

  water flowing horizontally through permeable rock below the water table due to gravity
• what are the outputs in the drainage basin?

  evaporation

  transpiration

  channel flow
• evaporation?

  water turning into water vapour due to solar radiation
• transpiration?

  evaporation from the surface of leaves
• evapotranspiration?

  the loss of water from the soil both by evaporation from the soil surface and by transpiration from the leaves of plants
• channel flow?

  AKA river discharge - the water leaving the drainage basin through a river or stream
• what is a drainage basin?

  the area surrounding a river where the rain falling on the land flows into that river --> open, local hydrological systems
• what is the watershed?

  the boundary of a drainage basin - any precipitation falling beyond the watershed enters a different drainage basin
• what affects the drainage density of a drainage basin?

  • larger drainage basins with steep sides have the capacity to catch precipitation and move it quickly into river channels --> they are likely to have a large number of streams = high drainage density
  • smaller drainage basins or ones with fewer streams have a low drainage density
• what are the 3 types of precipitation?

  frontal

  orographic

  convectional
• frontal precipitation?

  warm air is less dense than cool air, when warm air meets cool air, the warm air is forced above the cool air, it cools down as it rises
• orographic precipitation?

  when warm air meets mountains, it's forced to rise, causing it to cool
• convectional precipitation?

  when the sun heats up the ground, moisture on the ground evaporates and rises up in a column of warm air as it rises, it cools down
• how can precipitation patterns vary?

  • convectional precipitation is more likely to occur in the tropics and produce effects like monsoon seasons. this also occurs in the summer months at high latitudes e.g. arctic tundra
  • coastal areas often receive more precipitation than inland areas because water is evaporated from the oceans and falls as precipitation