Water Flashcards
what is a closed system?
a system of inputs, outputs, stores and flows, from which no matter enters or leaves , only energy does - in this case solar and gravitational potential
what % of global water is stored in oceans?
97%
what % of global water is stored in groundwater?
0.37%
what % of global water is stored in ice caps/glaciers?
2.41%
what % of global water is stored in rivers/lakes?
0.2%
what % of global water is stored in the atmosphere?
0.0001%
why is water important for ecosystems?
soil moisture is needed for plant growth, and rivers and lakes provide drinking water for animals
why is water important for humans?
groundwater, rivers and lakes provide drinking water and can make electricity, important for irrigation, industry and agriculture
what is the global water budget?
the annual balance of water fluxes and the size of water stores. oceans are the largest store, with a residence time of 3600 years
what is a drainage basin?
an open system of inputs, stores, transfers and outputs
what is the input in a drainage basin?
precipitation
what are the stores in a drainage basin?
surface water, interception storage, soil water, channel storage
what are the transfers in a drainage basin?
infiltration, percolation, throughflow, groundwater flow, channel flow, stem flow, overland flow
what are the outputs in a drainage basin?
river runoff, evaporation, transpiration
what factors influence river runoff?
basin size shape and relief, drainage density, soil type, type of precipitation, land use, rock type, temperature
what is convectional rainfall?
as the sun heats the lad and air above, warm air rises, cools and condenses, forming clouds, which rain. this is typical in UK summer
what is frontal rainfall?
warm moist air encounters colder more dense air at regions we call fronts, it is forced to rise above the colder denser air. As the warm air rises it cools, water droplets within it condense and clouds form.
what is orographic/relief rainfall?
moist air is forced to rise over a physical barrier such as a mountain range, as it rises, the warm air cools with height, water vapour condenses to form clouds and eventually it rains over Britain’s highland areas.
As the air descends to the East coast of Britain it warms slightly and there is less rainfall. This results in a rain shadow on Britain’s east coast
define river runoff
when water flows into the sea
define soil water
This occurs when the water infiltrates downwards into the soil.
define stem flow
This is when water flows down vegetation, e.g. a tree trunk.
define surface water
If the ground is hard then the rain lies on the surface in puddles until it soaks into the ground.
define transpiration
A process where water is lost from a plant through the stomata in its leaves into the atmosphere.
define throughflow
This occurs where water flows sideways through the soil.
channel storage
This occurs when the water enters the river and stays there until it reaches the sea.
define channel flow
This occurs when water from the adjacent land flows into a river.
define evaporation
A process where water is lost from the land and river into the atmosphere.