Water EQ1 Flashcards
define a store
stocks of water, places where water is held
define a flux
measurement of the rate of flow between stores
define a process
the physical factors which drive the fluxes of water between stores
what kind of system is the hydrological cycle
closed
what forces drive the hydrological cycle
solar energy and gravitational potential energy
define cryosphere
frozen water in the hydrological system
define blue water
freshwater stores in rivers, streams and lakes- visible componant in cycle
define green water
freshwater stored in soil and vegetation- invisible componant of cycle
What are the main stores of water in order of percentage content
oceans (96%)
ice caps and glaciers (2%)
groundwater (1%)
rivers and lakes (0.01%)
What is the composition of freshwater stores
Ice caps and glaciers (69%)
groundwater (30%)
rivers and lakes (1%)
define residence time
the average time a water molecule will spend in a store or reservoir
which type of store has the longest residence time
ice caps- 15 000 years
which type of store has the shortest residence time
atmospheric moisture- 10 days
define drainage basin
a subsystem within the hydrological cycle. it is an open system with inputs and outputs
how does climate effect the drainage basin cycle
influences the type of precipitation and the amount of precipitation overall and the amount of evaporation. climate can also in some locations have an impact on vegetation type
how soil effects the drainage basin cycle
soil determine the amount of infiltration and throughflow and type of vegetation
how geology effects the drainage basin cycle
impacts subsufrace processes like percolation and groundwater flow as well as soil formations
how relief effects the drainage basin cycle
impact amount of precipitation and runoff
how vegetation effects the drainage basin cycle
presence or absense of precipitation has major impact on infiltration, interception and occurrence ofoverland flow as well as transpiration rates
human factors affecting the drainage basin cycle
deforestation abstraction construction of dams river defences overpopulation pollution (industial and agricultural) global warming unbanisation
define water budget
annual balance between input and output
equation to calculate water budget
precipitation= streamflow + evapotranspiration +/- changes in store
define river regime
annuel variation in discharge or flow of a river
major factors effecting regime of a river
drainage basin area maximum altitude variation in altitude geology mean annual precipitation mean discharge main land use
define simple regime
a river which experiences periods of seasonally high and low discharge contained within one climactic zone and relief
define complex regime
larger rivers cross several different relief and climactic zones and therefore experience the effects of different seasonal climactic events
define antecedent conditions
ground conditions before a storm eg) dry or already saturated
Define vegetation storage
Moisture taken up by vegetation and held within plants
Define surface storage
Surface water in lakes, rivers and ponds
Define groundwater storage
Water held within permeable rocks, also known as aquifers
Define channel storage
Water held in rivers and streams
Define infiltration
Water entering the top soil, most common in slow or steady rainfall
Define through-flow
Also known as interflow, water seeping laterally through the soil below the surface but above the water table
Define percolation
The downward seepage of water through rock due to gravity, usually in permeable rocks
Define stem flow
Water flowing down plant stems or drainpipes
Define base flow
Also known as groundwater flow, slow moving water seeping into a channel
Define channel flow
The volume of water flowing within a river channel
Define surface runoff
Also called overland flow. Flow over the surface during intense storms or when the ground is frozen, saturated or impermeable
Define river discharge
The volume of water passing a certain point in the channel over a certain amount of time
