GLOBAL SYSTEMS Flashcards
(120 cards)
1
Q
What is a drainage basin?
A
The area drained by a river and its tributaries.
2
Q
What drives the hydrological cycle?
A
Solar energy and gravity.
3
Q
What are the main inputs of a drainage basin?
A
Precipitation.
4
Q
What are the main outputs of a drainage basin?
A
Evapotranspiration and runoff.
5
Q
How does intense rainfall affect the water cycle?
A
Causes infiltration excess, increased surface runoff, and potential flooding.
6
Q
What is interception in the hydrological cycle?
A
Vegetation catching and slowing precipitation.
7
Q
Which type of forest has the highest interception loss?
A
Temperate pine forests.
8
Q
What does stemflow mean?
A
Water flowing down tree trunks and plant stems.
9
Q
What is depression storage?
A
Water collected in hollows and depressions as puddles or ponds.
10
Q
Define evapotranspiration.
A
Combined water loss from evaporation and transpiration.
11
Q
What is infiltration?
A
Water soaking into soil from the surface.
12
Q
When is infiltration capacity exceeded?
A
During heavy rainfall or if soil is saturated/frozen.
13
Q
What is overland flow?
A
Water moving across the surface due to saturated or impermeable ground.
14
Q
What is soil moisture deficit?
A
When evaporation exceeds moisture input, leading to dry soil.
15
Q
What is field capacity?
A
The maximum amount of water soil can retain after drainage.
16
Q
What is throughflow?
A
Water movement through soil layers parallel to the surface.
17
Q
What is groundwater flow?
A
Slow movement of water through permeable bedrock.
18
Q
What is the channel store?
A
The river itself storing water.
19
Q
What type of energy drives evaporation?
A
Solar power.
20
Q
What process converts gravitational potential energy into kinetic energy?
A
Precipitation falling to Earth.
21
Q
What is a river regime?
A
Annual pattern of river flow.
22
Q
How does temperature affect river regimes?
A
Influences evaporation and transpiration.
23
Q
Name a river with a tropical regime.
A
River Sonjo, Tanzania.
24
Q
Name a river with a temperate regime.
A
River Thames, UK.
25
How do dams affect river regimes?
Reduce variability by storing and releasing water.
26
What is a flood hydrograph?
A graph showing river discharge in response to rainfall.
27
What is baseflow?
Steady flow from groundwater between storms.
28
What is stormflow?
Fast transfer of water from rainfall events.
29
What causes a steep rising limb on a hydrograph?
Overland flow.
30
What is lag time?
Time between peak rainfall and peak discharge.
31
How does vegetation affect discharge?
Intercepts water and increases lag time.
32
How does rock permeability affect discharge?
Permeable rock reduces discharge.
33
How does land relief affect discharge?
Steep slopes increase speed of runoff.
34
How does urbanisation affect hydrographs?
Increases surface runoff and peak discharge.
35
How do storm drains affect discharge?
Increase direct runoff into rivers.
36
How does deforestation affect runoff?
Increases surface runoff due to loss of interception.
37
How does soil saturation affect runoff?
Increases it due to reduced infiltration.
38
What is convective rain?
Caused by intense heating of the ground surface.
39
What is frontal rain?
Caused by the meeting of warm and cold air masses.
40
What is orographic rain?
Caused by air rising over mountains.
41
What is the collision-coalescence mechanism?
Droplets colliding and growing until they fall as precipitation.
42
What is the Bergeron-Findeisen process?
Growth of ice crystals in clouds that fall as snow or melt as rain.
43
What are climatic causes of excessive runoff?
Snowmelt, monsoon rains, hurricanes.
44
What human activities increase runoff?
Deforestation, agriculture, urbanisation.
45
What is a water cycle deficit?
Outputs exceed inputs, reducing stores.
46
Define meteorological drought.
Period of below-average precipitation.
47
Define agricultural drought.
Lack of moisture for crops.
48
Define hydrological drought.
Low water reserves in rivers, lakes, and aquifers.
49
Define famine drought.
Leads to food shortages and humanitarian crises.
50
What is ENSO?
El Niño Southern Oscillation, influencing global droughts.
51
How does ITCZ affect drought?
Seasonal shifts change rainfall patterns.
52
Name a famous UK drought.
1976 drought—driest 16-month period in 250 years.
53
How does deforestation cause drought?
Reduces transpiration and atmospheric moisture.
54
How does intensive agriculture affect water availability?
Increases demand and reduces soil moisture.
55
What is the Ogallala Aquifer?
A major aquifer being depleted due to overuse.
56
What is desalination?
Removing salt from seawater.
57
What is virtual water trade?
Importing water-intensive products from water-rich countries.
58
What is an artificial store?
Reservoirs built to capture water.
59
How can leakage reduction help?
Prevents unnecessary water loss.
60
What is the carbon cycle?
Movement of carbon through the Earth’s spheres.
61
What is carbon sequestration?
Capturing and storing atmospheric carbon.
62
What are fast carbon flows?
Photosynthesis, respiration, decomposition.
63
What are slow carbon flows?
Weathering, sedimentation, volcanic release.
64
What is the physical pump?
Ocean absorption of CO2 via diffusion.
65
What is the biological pump?
Phytoplankton absorb CO2 via photosynthesis.
66
Where is the largest terrestrial carbon store?
Tropical rainforests.
67
What role do tropical rainforests play in the carbon cycle?
Active carbon sinks with rapid exchange.
68
How do grasslands store carbon?
Through soils and seasonal vegetation.
69
What are peatlands?
Carbon-rich wetlands with thick organic soil.
70
What percent of UK soil carbon is in peatlands?
Over 50%.
71
How does deforestation affect carbon storage?
Releases stored carbon and reduces sequestration.
72
What is afforestation?
Planting trees to absorb CO2.
73
How does agriculture reduce SOC?
Overworking soil leads to carbon loss.
74
What was the Dust Bowl?
1930s US soil erosion event reducing carbon stores.
75
What threatens peatlands?
Extraction, drainage, erosion, wildfires.
76
How can peatlands be restored?
Rewetting, re-vegetation, conservation.
77
Why are peatlands important?
Store double the carbon of global forests.
78
How are water and carbon linked?
Through shared roles in ecosystems and climate regulation.
79
What increases atmospheric carbon in the UK?
Industrialisation and fossil fuel use.
80
What is the energy budget?
Balance between incoming solar radiation and outgoing heat.
81
How does increased CO2 affect the energy budget?
Retains more heat, changing the climate.
82
What is positive feedback?
A change that amplifies effects (e.g., permafrost melting).
83
What is negative feedback?
A change that stabilizes a system (e.g., cloud formation).
84
What is the methane feedback loop?
Melting permafrost releases methane, worsening warming.
85
What is the cryospheric feedback loop?
Melting ice reduces albedo, increasing warming.
86
What is the marine feedback loop?
Warm oceans reduce CO2 absorption, increase emissions.
87
What was the impact of Mount Pinatubo on CO2?
Cooled the planet, reduced respiration rates.
88
What is desertification’s effect on cycles?
Reduces water and carbon storage capacity.
89
Define source (river).
The beginning point of a river.
90
Define mouth (river).
Where the river flows into a larger body of water.
91
Define tributary.
A smaller stream or river joining a larger one.
92
Define confluence.
Where two rivers meet.
93
Define percolation.
Water moving from soil into bedrock.
94
Define throughflow.
Horizontal movement of water in soil.
95
Define infiltration.
Water soaking into the ground.
96
Define evapotranspiration.
Water loss via evaporation and plant transpiration.
97
Define saturation excess.
Soil is full and can’t absorb more water.
98
Define infiltration excess.
Rainfall exceeds the soil’s infiltration capacity.
99
Define capillary action.
Movement of water through soil due to surface tension.
100
Define carbon sequestration.
Natural or artificial process of capturing and storing atmospheric CO2.
101
How does deforestation affect both the water and carbon cycles?
Increases surface runoff, reduces transpiration and carbon sequestration.
102
How do plants link the water and carbon cycles?
They take up water via roots and carbon via photosynthesis, releasing water through transpiration.
103
What role does the atmosphere play in both cycles?
Stores water vapor and carbon dioxide, both crucial for climate regulation and plant growth.
104
How does soil moisture affect carbon storage?
Wet soils slow decomposition, increasing carbon storage; dry soils speed it up, releasing CO2.
105
What is the role of wetlands in both cycles?
Wetlands store water and sequester large amounts of carbon in anaerobic soils.
106
How does climate change intensify the water cycle?
Increases evaporation, leading to more intense and frequent rainfall events.
107
How does climate change affect the carbon cycle?
Warmer temperatures accelerate decomposition, increasing CO2 emissions.
108
What happens to carbon sequestration during drought?
Reduced plant growth leads to less carbon absorption from the atmosphere.
109
How does increased atmospheric CO2 affect precipitation?
Triggers warming, increasing evaporation and thus rainfall in some regions.
110
What is the cryospheric feedback loop?
Melting ice lowers albedo, warming the planet, increasing water vapor and CO2 release.
111
What is a positive feedback loop in the water-carbon system?
Thawing permafrost releases CO2 and CH4, which enhance warming and further thawing.
112
What is a negative feedback loop involving water and carbon?
Increased CO2 may boost plant growth, increasing transpiration and cooling the air slightly.
113
How can peatland drainage create a feedback loop?
Releases stored carbon and dries soils, increasing decomposition and CO2 emissions.
114
How do oceans act as a feedback mechanism?
Warm oceans absorb less CO2 and release more, intensifying greenhouse effects.
115
What is the role of phytoplankton in feedback loops?
Absorb CO2 for photosynthesis and may promote cloud formation, cooling the climate.
116
How does urbanisation affect the water-carbon relationship?
Increases runoff and reduces vegetation cover, lowering carbon uptake and disrupting local hydrology.
117
How does intensive agriculture impact both cycles?
Increases water extraction and soil degradation, reducing water retention and carbon storage.
118
How does reservoir construction alter both cycles?
Changes river discharge and can release CO2 and methane from submerged vegetation.
119
What is the role of afforestation in managing both cycles?
Enhances carbon uptake and improves infiltration, reducing runoff and flooding.
120
How does climate mitigation policy link water and carbon cycles?
Policies like REDD+ address carbon storage in forests, which also regulate water flow.
