3.1.1.2 water cycle W&C

Question 1

what are the 5 subsystems in the water cycle

Answer 1

hydrosphere, biosphere, cyrosphere, atmosphere and lithosphere

Question 2

what is the lithosphere

Answer 2

outermost layer of the earth, includes the crust and the upper mantle

Question 3

what is the hydrosphere

Answer 3

all the water on earth, may in liquid, gas or solid form

Question 4

what is the atmosphere

Answer 4

the layer of gas between the earths surface and space, held in place by gravity

Question 5

what is the biosphere

Answer 5

the part of the earths system where living things are found, all living things on earth

Question 6

what is the cryosphere

Answer 6

includes all parts of the earths system where it is cold enough for water to freeze

Question 7

what percentage of water is in oceans

Answer 7

96.9%

Question 8

what percentage of water is in the cryosphere

Answer 8

1.9%

Question 9

what percentage of water is terrestrial

Answer 9

1.1%

Question 10

what percentage of water is in the atmosphere

Answer 10

0.001%

Question 11

what percent of the earths surface is covered by oceans

Answer 11

72%

Question 12

what is included in the cryosphere

Answer 12

sea ice (Artic ocean), ice shelves (Greenland and Iceland), ice sheets (land ice extending into the water), ice caps and permafrost (1-500m thick)

Question 13

what is the residence time of cyrospheric water

Answer 13

15,000 years (longest)

Question 14

what is included in terrestrial water

Answer 14

rivers, lakes, wetlands, ground water and soil water

Question 15

why is atmospheric water vital

Answer 15

keeps the atmosphere at a temperature that maintains life

Question 16

what is the residence time of atmospheric water

Answer 16

10 days

Question 17

what are the three states of water

Answer 17

solid = ice
liquid = water
gas = water vapour

Question 18

what is latent heat

Answer 18

when water changes state is needs heat or releases heat

Question 19

what is evaporation

Answer 19

transfer of water from liquid state to gas

Question 20

what is transpiration

Answer 20

water is lost from surface of vegetation when water vapour is realised through the stomata in leaves

Question 21

what affects the rate of evaporation

Answer 21

amount of solar energy, humidity, temp of air, availability of water

Question 22

what is condensation

Answer 22

air cools and holds less water vapour this means it will reach a point of saturation which is called dew point, excess water in the air will then be converted into liquid water

the water will need something to condense on this can be particles such as dust or smoke, or surfaces such as leaves, grass or windows that are below dew point temp

Question 23

when do clouds form

Answer 23

when evaporated water condenses into a concentration nuclei

Question 24

what conditions are needed for water to evaporate and rise

Answer 24

high temps, leads to high cloud coverage along the equator

Question 25

what is precipitation

Answer 25

atmospheric water returning to the terrestrial system

Question 26

what is the direct cause of all precipitation

Answer 26

condensation

Question 27

what are the 3 types of rainfall

Answer 27

frontal, relief/orographic and conventional

Question 28

what is orographic rainfall

Answer 28

when air is forced to rise over hills, cools and condenses and forms rainfall

Question 29

what is frontal rainfall

Answer 29

warm air meets cold air, warm is less dense air rises and cools, condenses and forms rain

Question 30

what is conventional rainfall

Answer 30

localised warm surfaces heat air above, this expands comes less dense and rises, forming rainfall

Question 31

how many glacial and interglacial cycles have there been in the past 740,000 years

Answer 31

8 cycles

Question 32

what happened in the last major glacial period

Answer 32

sea levels were approx 120m lower than present and continental glaciers covered much of Europe and North America, cause an interruption to the hydrological cycle

Question 33

what is involved in an interglacial period

Answer 33

more melting than freezing which allows the hydrological cycle to perform as it does today, water can cycle between subsystems as it is not trapped in the cryosphere

Question 34

what is runoff

Answer 34

atmospheric moisture that is transferred to the oceans on the surface or as groundwater

Question 35

what is a key process determining how much water runs off

Answer 35

infiltration

Question 36

when is surface runoff generated

Answer 36

when rainfall intensity is greater than infiltration capacity or when rain falls on soil that is already saturated

Question 37

what is a drainage basin

Answer 37

the area which all water I’d drained by the same river and it’s tributaries

Question 38

what factors affect flows in a drainage basin

Answer 38

vegetation density, soil porosity, slope gradient, precipitation intensity and water table depth,

Question 39

what is watershed

Answer 39

an imaginary line which separates one drainage basin from another

Question 40

what are human related factors that cause change at a local scale

Answer 40

deforestation, urbanisation and farmers digging drainage ditches

Question 41

what is the water balance

Answer 41

shows the balance between the inputs and outputs

Question 42

when does the water balance change

Answer 42

with the change of seasons

Question 43

what is the water balance like in the winter

Answer 43

precipitation exceeds potential evaporation, leads to water surplus, soils will be saturated, overland flow encouraged and river levels will be high

Question 44

what will the water balance be like in the summer

Answer 44

potential evapotranspiration will exceed precipitation, soil starts to dry out, at the end of the season there will be a deficit

Question 45

what is a flood/storm hydrograph

Answer 45

how river discharge changes as a result of heavy rainfall

Question 46

what is a river regime

Answer 46

the variability in the discharge throughout the course of a year in response to precipitation, temperature, evapotranspiration and drainage basin characteristics

Question 47

what are the natural changes in the water cycle which cause variation

Answer 47

storm events, drought and seasonal changes

Question 48

how do storm events cause variation

Answer 48

amounts and intensity of precipitation can affect amount of runoff, heavy storms cause higher discharge

Question 49

how can drought cause variation

Answer 49

a reduction in water in rivers and lakes, vegetation dies which reduces transpiration, interception etc, soils dries out

Question 50

what human activities cause change in the water cycle

Answer 50

farming practices, land use change and water abstraction

Question 51

how do framing practices cause change in the water cycle

Answer 51

ploughing breaks topsoil which allows greater infiltration resulting in less runoff, irrigation adds extra water to the system, drainage systems lead to a more rapid transfer of water to the nearest river system and livestock may compact soil resulting in more runoff

Question 52

how does land use change cause changes in the water cycle

Answer 52

urbanisation means more impermeable surfaces, water cannot infiltrate increasing overland flow and makes flooding more likely deforestation is the removal of trees which leads to increased surface runoff and soil erosion, interception rates are reduced, recited infiltration due to less roots in soil

Question 53

how does water abstraction cause change in the water cycle

Answer 53

the extraction of water from rivers or ground water aquifers, water stores are at danger of becoming depleted as rate of recharge is slower than rate of use there is also a risk of contamination by inflowing sea water if the water table drops below sea level