Water Cycle and Water Insecurity EQ1 Flashcards
The planting of trees in an area that has not been forested in recent times
Afforestation
A measure of the proportion of the incoming solar radiation that is reflected by the surface back into the atmosphere and space
Albedo
The normal, day-to-day discharge of the river fed by groundwater flow
Base flow
Water is stored in rivers, lakes and groundwater in liquid form
Blue water
The area of land drained by a river and its tributaries
Catchment
The flow of water in streams or rivers
Channel flow
The storage of water in streams or rivers
Channel storage
The change from a gas to a liquid
Condensation
Often associated with intense thunderstorms, which occur widely in areas with ground heating such as the Tropics and continental interiors.
Convectional rainfall
Areas of the Earth where water is frozen into snow or ice
Cryosphere
A period of sustained, moderately intensive rain; it is associated with the passage of depressions
Cyclonic rainfall
The cutting down and removal of all or most of the trees in a forested area
Deforestation
The temperature at which dew forms; it is a measure of atmospheric moisture
Dew point
The conversion of water to vapour, as a result of the sun’s heating and air movement The change in state of water from a liquid to a gas
Evaporation
The combined effect of evaporation and transpiration
Evapotranspiration
The part of a storm hydrograph in which the discharge starts to decrease
Falling (recessional) limb
The rate of flow between the stores
Fluxes
Ancient, deep groundwater from former pluvial (wetter) periods
Fossil Water
Water stored in the soil and vegetation
Green water
The slow transfer of percolated water underground through pervious or porous rocks
Groundwater flow
The movement of water from the ground surface into the soil
Infiltration
The maximum rate at which rain can be absorbed by a soil
Infiltration capacity
Where water is captured by vegetation, or buildings and hard surfaces, before reaching the soil
Interception
Water retained by plant surfaces and later evaporated or absorbed by the vegetation and transpired
Interception loss
The time between peak rainfall and peak discharge
Lag time
Concentrated on the windward slopes and summits of mountains
Orographic rainfall
The time when the river reaches its highest flow
Peak discharge
The transfer of water from the soil into the bedrock beneath
Percolation
Lines of concentrated water flow between soil horizons to the river channel
Percolines
The water loss that would occur if there was an unlimited supply of water in the soil for use by vegetation
Potential Evapotranspiration
The movement of water in any form from the atmosphere to the ground
Precipitation
The physical mechanisms that drive the fluxes of water between the stores
Processes
A dry area on the leeward side of a mountainous area (away from the wind). The mountains block the passage of rain-producing weather systems and cast a “shadow” of dryness behind them.
Rain shadow
Planting trees in places with recent tree cover, replacing lost primary forests
Reforestation
The average time a water molecule will spend in a reservoir or store
Residence time
The part of a storm hydrograph in which the discharge starts to rise
Rising limb
The annual variation in discharge or flow of a river at a particular point or gauging station, usually measured in cumecs
River regime
The upward movement of the water table into the evaporation zone
Saturated overland flow
Water held within the soil
Soil moisture storage
This is when water trickles along twigs and branches and then down the trunk
Stem flow
Stocks where water is held, such as the oceans, lakes etc.
Stores
The variation of discharge within a short period of time, usually in response to a period of rainfall
Storm hydrograph
The movement of water that is unconfined by a channel across the surface of the ground. Also known as overland flow
Surface run-off
Any surface water in lakes, ponds, puddles
Surface storage
These approaches study the hydrological phenomena by looking at the balance of inputs and outputs, and how water is moved by stores and flows
Systems approach
When the rainfall persists or is relatively intense and the water drops from the leaves, twigs, needles etc.
Throughfall
The lateral transfer of water down slope through the soil via natural pipes and percolines
Throughflow
The diffusion of water from vegetation into the atmosphere, involving a change from a gas to a liquid
Transpiration
Any moisture taken up by vegetation and held within plants
Vegetation storage
The balance between precipitation, evaporation and run-off (the difference between inputs and outputs)
Water budget
The high land which divides and separates waters flowing to different rivers
Watershed
