Moving Water

Movement (causes): energy gradients, change in energy from high to low

• dictated by elevation change (gravity) and temperature change

The amount of water on Earth does not change

• on the global system scale, no water exits/enters the system

Water Budget

1. Determines the balance of how much water is entering and exiting a system, this is always in open systems

   • inflow = enter

   • outflow = exit

   • inflow - outflow = change in storage

2. Regional Water Budgets: determine the amount of water in a regional area

   • inflow > outflow = (positive) increase

   • inflow < outflow = (negative) decrease

Storage Reservoirs

1. Areas where water is held/stored for extended periods of time

   • like lakes, oceans, glaciers

   • a river is a reservoir in motion

2. Flow/Flux Terms (Movement between storage reservoirs)

   1. Precipitation: atmosphere to another reservoir

   2. Evaporation: surface water to atmosphere (liquid-vaporization-gas-atmosphere)

   3. Evapotranspiration: surface water to atmosphere, evaporation through plant leaves

   4. Condensation: stays within the atmosphere, gas phase that is condensed into liquid (preparing for precipitation)

   5. Infiltration and Percolation: from surface water to ground water, the entry and movement of liquid water

      • infiltration: hitting the surface

      • percolation: movement down through the ground

   6. Sublimation: transition from solid water in glaciers to liquid water, with the release of gas into the atmosphere

   7. Subsurface Water Flow: from surface water to ground water, moving water below the land surface