geography

• The hydrological cycle is the continual transfer of water between the land, ocean, and atmosphere
• Drainage Basin


  An area of land drained by a river and its tributaries
• Tributary


  A stream which flows into a river
• Watershed


  Boundary between river basins
• River Channel


  Where the tributaries meet and form a single stream
• Mouth


  The end of a river where it flows into a larger body of water
• Source


  The starting point of a river
• Through-flow


  Water flowing horizontally through the soil
• Percolation


  Water seeping down through the soil
• Evaporation


  The transfer of water from the sea to the air as vapor
• Surface runoff

  Water running over the land surface
• Width and depth of a river increase as discharge increases
• A river near its source will be on highland
• The river winds its way along protruding hillsides
• Energy is used to transport large boulders along the river bed
• Vertical erosion occurs
• Downstream, the river flows over flatter land and develops large bends called meanders
• The river widens and deepens downstream
• Load refers to the material carried by a river
• Lateral erosion occurs
• Gradient of a river decreases from source to mouth
• Gradient determines the steepness of the channel
• 'climate change is happening now, it is not some future threat'