Water and carbon cycles

• Precipitation

  water that falls from clouds and reaches Earth's surface as rain, snow, sleet, or hail.
• Evapotranspiration


  The evaporation of water from soil plus the transpiration of water from plants.
• Runoff


  Water that moves across the land surface and into streams and rivers
• Interception storage

  precipitation falls on the vegetation surfaces (canopy) or human cover. temporarily stored. Intercepted water either evaporated directly to the atmosphere, absorbed by the canopy surfaces or ultimately transmitted to the ground surface.

  
  

  Tropical rainforests intercept 58% rainfall
• Surface storage


  The total volume of water held on the Earth's surface in lakes, ponds and puddles.
• Soil water storage

  Water stored in the soil - clay 40-60%, sand 20-45%
• Groundwater storage


  The storage of water underground in permeable rock strata
• Channel storage


  Water held in a river or stream channel
• Vegetation storage

  Any moisture taken up by vegetation and held within plants
• Stemflow


  the flow of intercepted water down the trunk or stem of a plant
• Infiltration


  the process by which water on the ground surface enters the soil
• Overland flow


  water flowing across the soil surface on a hillslope, usually resulting from precipitation falling faster than the ground can absorb it
• Channel flow


  The flow of water in a river
• Throughfall


  Water that reaches the ground either directly or after being intercepted by vegetation.
• Throughflow


  Water flowing through the soil layer parallel to the surface
• Percolation


  The downward movement of water through soil and rock due to gravity.
• Ground water flow


  water running underground
• positive water balance


  precipitation exceeds evapotranspiration
• negative water balance


  Evapotranspiration exceeds precipitation
• Q + E + (S) = P


  runoff + evapotranspiration + change in storage = precipitation
• Relief rainfall


  caused by uplifting and cooling of moist air over mountains
• Frontal rainfall

  When a warm air mass meets a cold air mass the warm air rises
• Convectional rainfall


  Precipitation formed by rising currents of warm, moist air
• accumulation


  glacial system inputs due to snowfall
• ablation


  output of glacial system due to melting
• Sublimation


  solid to gas
• Condensation


  Gas to liquid
• latent heat


  the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature.
• Evaporation


  Liquid to gas
• closed system


  no energy or matter is transferred into + beyond system boundary - global
• open system


  matter and energy transferred from system across boundary into environment - ecosystems
• isolated system


  A system that can exchange neither energy nor matter with its surroundings.
• dynamic equilibrium


  balance between inputs and outputs
• positive feedback


  Feedback that tends to magnify a process or increase its output - negative effect
• negative feedback


  positive environmental effects
• example of negative feedback


  increased surface temp, increased evaporation, increased cloud cover, decreased radiation = cooling
• amount of water on earth

  71% of Earth is water
• amount of available fresh water

  3%
• amount of accessible fresh water


  1% = shortages and exploitation
• amount of groundwater storage

  20%