Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Geography - A LEVEL > Water balance and changes > Flashcards

Water balance and changes Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards World Geography flashcards
1
Q

what is a drainage basin

A

an area of land drained by a river and its tributaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is a catchment

A

the area of a drainage basin e.g. the amazons is 7 million km squared

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what creates dynamic equilibrium

A

water continually entering and leaving a drainage basin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is a river system

A

a river and its tributaries make up a river system also called a drainage basin/watershed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is a watershed

A

includes the river, all its tributaries and any groundwater resources in the area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the river mouth

A

the end of a river - where it empties into another body of water like the ocean, lake etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the water balance

A

the balance between inputs and outputs in a drainage basin - usually shown on a graph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the equation for the water balance

A

P = Q + E +/- changes in storage
P - precipitation
Q - runoff
E - evapotranspiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does a watershed mark

A

the boundary between two separate drainage basins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

are drainage basins open or closed systems

A

open systems - receive inputs and outputs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what happens to water in a drainage basin after precipitation

A

water will flow downstream from the source, tributaries will join together creating a confluence before flowing out to sea at the mouth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the 10 types of flowing

A

channel flow
surface runoff
infiltration
throughflow
percolation
interflow
groundwater flow
baseflow
throughfall
stemflow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is interflow

A

when water travels through permeable rock above the water table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is baseflow

A

when water feeds onto the channel through the banks and bed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how is water stored in the cycle; through interception

A

vegetation storage
surface storage
groundwater storage
channel storage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the outputs of water

A

evapotranspiration
evaporation
transpiration
runoff into the sea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the three factors that could affect the water balance (there are more than 3 but we only needed 3 examples)

A

temperature
human activity
rainfall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how could temperature affect the water balance

A

increases evaporation and transpiration in higher temperature.
decreases evaporation and transpiration in lower temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how does human activity affect the water balance

A

may release fossil fuels so there are more nuclei for clouds to from around so increased precipitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how could rainfall affect the water balance

A

more rainfall causes more inputs of water (precipitation)
less rainfall causes less inputs of water (precipitation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a catchment

A

the area of land within a drainage basin which includes everything within it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is river discharge

A

the volume of water passing a given point at a given time. Measured in cumecs (m**3/s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the equation of discharge

A

discharge = cross sectional area x velocity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

why is it important to monitor river discharge

A

can anticipate floods & shortages
detecting climatic and environmental change
allows the assessment and management of water resources, the design for water-related structures and flood warning schemes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is a method of measuring river discharge

A

the float method

26
Q

describe the steps of the float method

A
  1. mark two points along the channel (this is the distance)
  2. measure 3 depths and find the average (depth)
  3. measure the rivers width (width)
  4. fill a float bottle partially with water
  5. drop bottle and start the timer stop the timer when it reaches the second observer.
  6. repeat step 5 3 times and find the average (time)
  7. determine flow:
    width x depth x (distance / time) x correction factor
27
Q

what is a water budget

A

the annual balance between precipitation, runoff and evapotranspiration (inputs and outputs)

28
Q

what is the equation for the water budget

A

P = Q + E
P - precipitation
Q - runoff
E - evapotranspiration

29
Q

what does a positive water budget mean

A

water surplus (inputs > outputs)

30
Q

what does a negative water budget mean

A

water deficit (inputs < outputs)

31
Q

what do water budgets at a national/regional scale show

A

the amount available for human use

32
Q

what do water budgets at a local scale show us

A

the available soil water

33
Q

what happens to a water budget in the winter

A

precipitation exceeds evaporation - soil moisture is recharged until a surplus - water can then supply rivers

34
Q

what happens to a water budget in the summer

A

evaporation exceeds precipitation - soil water is utilised - by the second half of summer there is a deficit

35
Q

what happens to the water budget in autumn

A

precipitation increases and evapotranspiration falls allowing soil moisture to be recharged once more

36
Q

what are the main human impacts on the global water cycle

A

deforestation
water abstraction
agriculture

37
Q

what happens to the percentage of surface runoff when human settlements are created

A

goes from less than 1% to 20-30% - increase

38
Q

what happens to the percentage of evapotranspiration when human settlements are created

A

goes from 40-50% to 20-30% - decrease

39
Q

what happens to the percentage of interflow when human settlements are created

A

goes from 20-30% to 0-30% - decrease

40
Q

what happens to the percentage of groundwater when human settlements are created

A

goes from 10-40% to 10-20% - decrease

41
Q

Where is the river kennet

A

in southern England in Wiltshire and Berkshire

42
Q

how large is the river kennet catchment

A

1200 km**2

43
Q

what material is the upper catchment of the river kennet

A

chalk which is highly permeable so groundwater is the largest flow

44
Q

when the water from the river kennet is filtered through chalk what happens to it

A

it will have high oxygen levels and is fast flowing with exceptional clarity

45
Q

what are the native fauna in the river kennet catchment

A

white clawed crayfish, otters, water voles

46
Q

what is the largest Urban area relying on a water supply from the river kennet

A

Swindon with a population of 220,000

47
Q

what does the river kennet supply water for

A

local industries: agriculture, public use

48
Q

which river abstracts water from the upper catchment with boreholes

A

The river Thames - none of the water is returned

49
Q

what are the impacts of water extraction on the river kennet

A
  1. rates of extraction exceed rates of recharge reducing flows by 10-14%
  2. during the 2003 drought flows fell by 20% in the 1990 with dry conditions they fell by 40%
  3. lower flows have reduced flooding
  4. springs have dried up and reduced saturated overland flow
50
Q

Where is California located

A

California is a state on the far west of North America

51
Q

what foes California have that is used in periods of drought

A

has crucial water reserves used in droughts

52
Q

since which year has California been regulating surface water

A

since 1914

53
Q

when did California start regulating groundwater

A

2014 (100 years after the regulation of surface water)

54
Q

what percentage of the population rely on groundwater supplies in California

A

85% of the population and $50 billion of the agriculture industry

55
Q

how many people rely solely on groundwater

A

6 million

56
Q

how much of the water supply do groundwater stores usually supply in California

A

30-40% however in drought this has almost doubled

57
Q

Which valley is using pumps and causing the groundwater stores to drain

A

Central Valley where they are are withdrawing twice as much as nature is replenishing.

58
Q

what does groundwater extraction cause

A

ground subsidence

59
Q

what is ground subsidence

A

when water is removed from the groundwater basin clay layers are drained causing clay layers to compact which cause compaction in aquifers.

60
Q

what does the compaction in ground subsidence cause

A

compaction leads to fewer pore spaces so recharging is harder

61
Q

what act was adopted in California 2014

A

Sustainable Groundwater management act (SGMA) - groundwater is managed sustainably - if plans are inadequate the state authority can step in

62
Q

what are the solutions to more water being taken out than can be replenished

A

control groundwater withdrawals
deposit water into water storage either naturally or artificially:
- naturally by recharge
- artificially by creating a recharging pond so water will infiltrate

Geography - A LEVEL (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions