Water and Carbon Flashcards
(150 cards)
1
Q
What is a system?
A
A set of interrelated events or components working together, that forms a unified whole and also describes the transfer of energy.
2
Q
What are stores?
A
individual elements or parts of the system
3
Q
What are flows/transfers?
A
Links between components
4
Q
What is an open system?
A
Transfers both matter and energy to the surrounding environment as well as within the system.
5
Q
What is a closed system?
A
Transfers energy to the surrounding environment but not matter.
6
Q
What is an isolated system?
A
These have no interaction with anything outside the system, there is no input or output of energy or matter.
7
Q
Whats an example of an open system?
A
Drainage basins
8
Q
Whats an example of an closed system?
A
Earth’s water cycle
9
Q
What is dynamic equilibrium?
A
The balance between inputs and outputs in a system.
10
Q
What is negative feedback?
A
When a change in a system leads to a series of events that counteract and reduce the initial change.
11
Q
What is positive feedback?
A
When an initial change in a system leads to further changes that amplify the initial effect.
12
Q
What is an example of a positive feedback system?
A
Ice sheets have high albedo, reflect solar radiation, temperature cools, more ice, increased albedo, increased cooling.
13
Q
What is an example of a negative feedback system?
A
Large amounts of Co2 are emitted, Co2 in atmosphere increases, more co2 causes plants to grow more, plants remove more co2 from atmosphere, amount of co2 in atmosphere decreases.
14
Q
What is terrestrial water?
A
Water on the land as:
-Ground water = Water that collects underground in the pore spaces of rocks.
-Soil water = Stored in pore spaces in upper layers soil, key in exchange of water between land surface and atmosphere through evapotranspiration.
-Surface water = Free flowing water of rivers, wetlands, lakes.
-Biological water = Water stored in all biomasses.
15
Q
What is atmospheric water?
A
Water found in the atmosphere - mainly as vapour (GHG), some as liquid and ice crystals.
16
Q
What is Ocean water?
A
Water stored in the oceans and seas but doesn’t include inland seas. Alkaline and contains dissolved salts which allow it to stay liquid below 0 degrees.
17
Q
Describe the composition of the Earth’s water
A
Largest proportion of the Earth’s water (95.6%) is stored in the oceans.
Only 2.5% of the Earth’s water is freshwater.
18
Q
Describe the hydrosphere
A
A discontinuous layer of water on the Earth’s surface. It includes all liquids on the Earth’s surface including river’s lakes, seas, and oceans.
19
Q
Describe the cryosphere
A
The cryosphere describes water in solid form on the Earth’s surface e.g. glaciers and ice sheets.
20
Q
Describe some cryospheric water stores
A
-Ice caps e.g. the Iceland ice cap = Thick layers of ice on land, usually found in mountainous area.
-Permafrost e.g. North Alaska slope = Ground material that remains below 0 degrees for at least 2yrs. Formed during glacial periods.
-Alpine glaciers e.g. Mer de Glace , France = Thick masses of ice in deep valleys, fed by ice from ice caps
21
Q
Describe the Earth’s ice sheets (cryosphere)
A
An ice sheet is a mass of glacial land ice extending more than 50,000 km2.
The two major ice sheets cover most of Greenland and Antarctica.
22
Q
Explain the role of cryosphere change in the water cycle:
A
-The cryosphere refers to water stored as ice on Earth’s surface.
-In periods of cooling, the cryosphere will grow, so water cycle is slowed considerably as ice restricts return of water.
-Winter months - snowfall + frozen ground interrupts water transfers e.g. infiltration, affects magnitude of stores.
23
Q
Describe the lithosphere
A
The outermost layer of the Earth, it includes the crust and the upper parts of the mantle plus any rocks and soil.
24
Q
What is latent heat?
A
The heat required to convert a solid to a liquid or vapour, or a liquid into a vapour, without change of temperature.
25
What are factors driving change in the water cycle?
The processes which cause water to change state and are what are responsible for driving change in the size of water stores.
26
What are the 3 main changes that are impacting the magnitude of stores in the water cycle?
-Climate change
-cloud formation and changes in precipitation
-cryospheric processes
27
Explain how climate change impacts the magnitude of stores in the water cycle
-At the peak of the last ice age, about 1/3 of the Earth's surface was covered in glaciers and ice sheets. So sea levels fell by over 100m compared to today.
-During warmer periods (3 mill yrs ago), ocean levels were 50m higher than today as ice has melted.
28
Explain how cloud formation and changes in precipitation impacts the magnitude of stores in the water cycle
-The global atmospheric circulation model is the driving force for cloud formation and precipitation being unevenly distributed.
-Equator = high temps = high evaporation. Warm air rises, cools and condenses forming clouds (low pressure) in the ITCZ.
-In mid latitudes, cloud formation is driven by the convergence of warm air from the tropics and cold from the arctic = low pressure.
29
What are the factors affecting evaporation?
-Temperature of the air
-Amount of solar energy
-Availability of water
-Humidity of the air
30
What is dew point temperature?
Temperature cools to at which it can’t hold any more water and becomes saturated.
31
What are condensation nuclei?
Tiny particles that are below dew point temperature that water molecules condense on e.g. smoke, dust.
32
What is sublimation?
Water vapour turning to a solid
33
What is the quarternary period?
The most recent glacial period that started 2.58 mill years ago and continues today.
34
When do glacial periods occur?
When due to the volume of ice on land, sea levels are much lower than present.
35
What is Ablation?
Where mass is lost rather than gained in the lower parts of the glaciers.
36
What is Accumulation?
Where more mass is gained in the upper parts of the glacier than is lost.
37
When do interglacial periods occur?
When global ablation exceeds accumulation and the hydrological cycle as we know it today returns.
38
What is an Aquifer?
A permeable or porous rock which stores water that formed slowly over a long period of time.
39
What is a fossil aquifer?
An aquifer which is formed during wetter climatic periods, that may last for 10,000 years.
40
Describe the distribution of ground water aquifers?
The majority of Aquifer systems are found throughout South America, Africa and Europe. Some are also found in Indonesia and Australia.
41
What is a drainage basin/catchment area?
The area of land drained by a particular river and its tributaries. Can vary in size from a few sqkm to millions of sqkm.
42
What is the watershed?
-The physical boundary/ the edge of a drainage basin.
-Marked by higher land than the surrounding area.
-Water in the watershed is then drained into rivers via their tributaries.
43
Why are drainage basins open systems?
Energy in the form of solar energy enters the system. Matter in the form of precipitation enters the system, and can leave via evapotranspiration.
44
What are the inputs and outputs of a drainage system?
Inputs = precipitation
Outputs = Transpiration, evaporation, river discharge.
45
What are the flows of a drainage basin?
Stemflow, throughflow, groundwater flow, through fall, infiltration, percolation, river/channel flow.
46
What are the stores of a drainage basin?
Vegetation storage, soil storage, interception storage, surface storage, groundwater storage.
47
How would storms affect the drainage basin?
Storms mean that more water is entering the drainage basin, this saturates the soil and increases the risk of flooding.
48
How would urbanisation affect the drainage basin?
Building on drainage basins means less water can infiltrate into the ground, increasing the risk of flooding.
49
How would farming affect the drainage basin?
Farming uses water from the basin, and practices such as ploughing can compact the soil, reducing the amount of water that can infiltrate into the ground.
50
How is the hill slope water cycle affected by natural factors?
-Storms = Intense rainfall increases the amount of rainfall reaching the ground and increases the magnitude of stores.
-Seasonal changes = Winter snowfalls and frozen ground interrupt the water transfers and affect the magnitude of stores.
51
How is the hill slope water cycle affected by human factors?
-Farming = Ditches drain land and water flows quickly at rivers. Irrigation increases water on the land.
-Deforestation = Removal of trees reduces interception and infiltration. Overland flow increases.
52
Define precipitation
The movement of water from the atmosphere to the ground surface. It can take several forms including rain, snow, sleet, hail and fog.
53
Define interception
Precipitation that falls on the vegetation surfaces or human made cover that is temporarily stored on these surfaces.
54
Define throughflow
When under the force of gravity, water moves downslope through the soil until it reaches a water body.
55
Define stemflow
The portion of precipitation intercepted by the canopy that reaches the ground by flowing down stems, stalks or trunks.
56
Define infiltration
The downward movement of water from the surface into the soil
57
Define soil storage
The amount of water stored in the soil, in pore spaces.
58
Define vegetation storage
When plants remove water from the soil and store it in their structure in order to survive.
59
Define transpiration
The loss of water from vegetation through stomata in the leaves and returns back to the atmosphere.
60
Define surface storage
When the soil is saturated, water builds on the surface as surface storage, usually in the form of puddles.
61
Define evapotranspiration
The total output of water via evaporation plus transpiration from the cycle
62
Define overland flow
Water flowing over the ground surface, may be due to saturated soil.
63
Define infiltration capacity
Water moving through the subsoil at a very slow rate under the influence of gravity.
64
Define percolation
The downward movement of water within the rock under the soil surface.
65
Define groundwater
Water held within the pore spaces in rocks after it has percolated through the rocks above.
66
Define groundwater flow
The slow movement of water through permeable rock under the force of gravity
67
Define channel flow
Water held in the channel as it moves through the drainage basin, also acts as a temporary store.
68
Define run-off
All of the water that enters a river channel and eventually flows out of the drainage basin.
69
Define discharge
Volume of water flowing through a river in a given time.
70
Define simple river regime
The regime of a river represents the annual average discharge of a river.
71
How many river systems are there in the UK?
1500
72
Describe rainfall patterns in the UK
Mountains in the North can drain areas receiving 5m a year, compared to the SE which has much lower rainfall.
Rainfall is evenly distributed in the UK. The west can get more.
73
Define water balance/budget
Within a drainage basin, the balance between inputs and outputs.
74
What is the equation used to show the water balance
Precipitation (P) = total runoff (streamflow) (O) + evapotranspiration (E) +/- changes in storage (S).
-The 2 most important parts are precipitation and evapotranspiration.
-evapotranspiration is closely related to prevailing temperature.
75
Define potential evapotranspiration
The amount of water that could be evapotranspirated from an area.
76
On a water balance graph, what is soil moisture re-charge?
When soil moisture store is filled again as precipitation is greater than evapotranspiration.
77
On a water balance graph, what is soil moisture utilisation?
When the water is used up by plants as potential evapotranspiration is greater than precipitation.
78
On a water balance graph, what is soil moisture defecit?
There isn't enough water for plants so they either wilt or adapt to survive dry conditions. Potential evapotranspiration is greater than precipitation.
79
On a water balance graph, what is soil moisture surplus?
All space in soil is filled, surplus in precipitation, overland flow can occur. Excess hasn't been used. Evapotranspiration is less than precipitation.
80
Define field capacity
The maximum amount of water soil can hold before it becomes saturated. A surplus can result in wet soil, high river levels and run-off.
81
Define water defecit
Evapotranspiration is in excess of precipitation and other moisture has been used.
82
How do the wet seasons change the water balance?
-Precipitation exceeds evapotranspiration
-Creates a water surplus
-Creates soil moisture surplus, and re-charges soil.
83
How do the dry seasons change the water balance?
-Precipitation lower than evapotranspiration
-Creates soil moisture defecit, excess is used by plants.
84
What is lag time on a hydrograph?
The time between peak rainfall and peak discharge
85
What is baseflow on a hydrograph?
Normal discharge of the river
86
What is storm flow on a hydrograph?
Discharge resulting from storm precipitation.
87
What is the rising limb on a hydrograph?
When storm water enters the drainage basin
88
What is the falling limb on a drainage basin?
When discharge begins to fall
89
What characteristics lead to a 'flashy' hydrograph?
Small basin size
Impermeable rock type
Saturated soil
Steep relief
Urbanisation (land use)
90
What characteristics lead to a 'flat' hydrograph?
Large basin size
Permeable rock type
Forests (interception) (land use)
gentle relief
Dry soil
91
Give some human causes of flooding
-Ploughing and grazing animals compact soil
-Impermeable areas of tarmac
-Wells sunk to supply settlements
-Streams channelled to aid drainage in farmland
92
Explain how the seasonal changes of summer impact the water cycle
-Vegetation grows more rapidly which increases interception and transpiration.
-Higher temps encourage higher evaporation
-Dry soils encourage more infiltration
93
Explain how the seasonal changes of winter impact the water cycle
-Vegetation dies back which decreases interception and transpiration.
-Lower temps mean less evaporation
-Soils may become saturated, increasing overland flow.
94
How can land use impact the water cycle?
Concrete and buildings create impermeable surfaces - leads to increased overland flow + soil water and groundwater stores are reduced.
95
How does deforestation impact the water cycle?
There is less interception of trees which means there is an increase in surface run-off. This means there is soil erosion and soil water stores are reduced.
96
What is the water table?
The boundary between unsaturated and saturated zones underground
97
Explain how drainage systems in the UK have impacted the water cycle
The drainage of the peatlands means the water table is lowered, changing rates of infiltration and evaporation.
98
What is **abstraction** and how does it change the water cycle?
Abstraction is the extraction of water from rivers of groundwater aquifers.
It means aquifers become depleted and can also become contaminated by salt water.
Can also result in low flow conditions in rivers.
99
What is the global carbon cycle?
The flow of carbon as it is transferred around the Earth in different forms
100
Describe how carbon atoms move through the carbon cycle in many forms
Transferred between organic and inorganic carbon.
Forms:
-Co2 - atmosphere, soil, ocean
-Methane
-Calcium carbonate - Rocks, skeletons
-Hydrocarbons
-Bio molceules
101
Describe the origins of carbon on Earth
Primary source = Earth's interior - stored in mantle, released at margins.
-Dissolved in oceans
-Held in biomass
102
Describe the atmosphere as a source of carbon
-Carbon is held as Co2
-Amount has increased due to greenhouse emissions.
103
Describe marine sediments and sedimentary rocks as a source of carbon
The largest store of carbon, long term store with rocks taking millions of years to form
104
Describe the pedosphere (soil) as a source of carbon
Plant litter in forests decomposes and produces carbon
Soil humus - comes from leaf litter decomposition and dispersed through soil by worms.
Soil (69%) holds more carbon than vegetation (31%)
105
Give some facts about biosphere as a store of carbon
31% of Earth's carbon is stored in plants.
35-65% of carbon is underground biomass.
2 largest forest carbon reserves = Boreal in Russia, Amazon.
106
Give some facts about hydrosphere as a store of carbon
-Surface layer where light penetrates so photosynthesis can occur stores 900Gtc.
-Living organic matter stores 30Gtc
-Dissolved matter stores 700Gtc
107
Explain how carbon is transferred to the soil around a tree (local scale)
-Leaf litter on the floor decomposes and the carbon is transferred into the soil.
-Root cell respiration and root death
108
How is carbon released into the atmosphere by trees (local scale)
By decomposers on leaf litter and plant respiration from the tree.
109
What role do animals have in the carbon cycle?
Respiration
When they die decomposers respire
110
What is a fast carbon cycle?
Operating on a daily basis and influences changes to carbon stores over decades and centuries. (Organisms breathing and digesting).
111
What is a slow carbon cycle?
Operates over millions of years (lithification, tectonic plate movements).
112
Give some examples of fast carbon cycles
Photosynthesis
Respiration
Decomposition
Combustion
113
Give some examples of slow carbon cycles
-Transfer of carbon into oceans from atmosphere and land surface
-Deposition of carbon compounds on ocean floor
-Tectonic plate movements
114
Give and describe some transfers in the carbon cycle
Decomposition - When organisms die they are consumed by decomposers e.g. fungi, bacteria, which respire. Carbon from their bodies is returned to the atmosphere.
Combustion - Organic material contains carbon which is released when burned.
Carbon sequestration - Transfer of carbon from atmosphere to plants, soils, rocks, oceans. Natural + human process.
115
Explain the impact of cold conditions on carbon stores and transfers
-Chemical weathering processes are more active because cold water holds more co2.
-Decomposers are less effective so carbon transfers to soil is less effective
-Forest cover would be different - affecting processes such as photosynthesis and respiration.
116
Explain the impact of warm conditions on carbon stores and transfers
-Decomposers would be more effective
-Melting of permafrost has led to carbon stores such as methane to be released.
-Increased forest cover - increased photosynthesis.
117
What much land surface is burned by wildfires every year and how much carbon does this release?
3-4 million km2
More than a billion tonnes of carbon
118
How do volcanic eruptions contribute to the carbon cycle?
Volcanoes emit around 130-380 million tonnes of co2 a year.
119
How does sulphuric acid influence the carbon cycle?
Sulphuric dioxide released is converted into sulphuric acid which forms fine droplets - increases reflection of radiation - cools earth.
120
Describe the patterns of Co2 emissions since the late 1950's and the main causes of this:
-There has been a rapid increase in atmospheric Co2 levels since 1950 (from 315ppmv to 400ppmv).
-This is due to the rapid industrialisation of developing countries (China) as well as continued demand by the world's industrialised nations (USA).
121
How does cement increase Co2 emissions?
Co2 is a byproduct of a chemical conversion process used in the production of a component of cement where limestone is converted to lime.
122
How important are land use changes to the carbon cycle?
Responsible for 10% of Co2 released globally, impacts short term stores and links to climate change.
123
What % of global Co2 emissions does deforestation account for?
20%
124
What % of anthropogenic Co2 emissions come from the combustion of fossil fuels?
90%
125
What % of the global population are urban populations supposed to reach by 2030?
60%
126
What rate are cities increasing by per week?
1.3 mill people
127
What % of total global land area do urban areas occupy?
2%
128
What % of global anthropogenic carbon emissions do urban areas account for?
97%
129
What is carbon sequestration?
Capturing Co2 from the atmosphere and putting it into long term storage
130
What is geological carbon sequestration?
Co2 is captured at its source and injected as a liquid deep underground in a variety of stores e.g. depleted oil reservoirs.
131
What is terrestrial carbon sequestration?
Use of plants to capture Co2 from the atmosphere. Carbon is then stored in stems and roots of plants.
132
What is the carbon budget?
Describes the amount of carbon that is stored and transferred within the carbon cycle.
133
Why is the carbon budget important?
Allows scientists to calculate how much Co2 humans can add to Earth's atmosphere before triggering the worst climate change effects.
134
What is the role of the carbon cycle on land?
-Carbon is stored in biomass, such as tropical and temperate forests.
-Carbon is transferred to the soil via leaf litter, roots and plant debris upon decomposition.
-Bacterial action in decomposition releases Co2 back into the atmosphere.
135
Explain the human impact on the carbon cycle on land
Clearing of vegetation is a major change to biomass and affects exchange of carbon between the atmosphere and soil.
Clearing vegetation by burning releases lots of stored carbon to the atmosphere.
136
What is the role of the carbon cycle in the ocean?
-Carbon is stored in the oceans as dissolved Co2, as bicarbonate ions in solution.
-Phytoplankton in surface waters absorb Co2 in photosynthesis.
-A 'carbon pump' operates within oceans transferring carbon from upper layers to the seabed.
-Carbon accumulates as ocean sediments in shallow seas leading to the natural sequestration of carbon.
137
Explain the human impact on the carbon cycle on the ocean
Warmer seas due to climate change are less able to absorb Co2 from the atmosphere and cause a reduction in phytoplankton activity.
138
What are some impacts of the carbon cycle in the atmosphere?
-Co2 combines with rainwater to form carbonic acid, leading to acidic rain. This causes terrestrial weathering and can contribute to ocean acidification.
-Atmospheric carbon is usually in the form of Co2 or CH4. Methane is 20x more powerful at absorbing solar radiation, but is shorter lived in the atmosphere than Co2.
139
How do changes to the carbon cycle affect global climate?
-Co2 is essential in the Earth's atmosphere to produce a planet habitable for life.
-Anthropogenic activity has resulted in more Co2 being released, and a reduced capacity for natural stores.
-Burning fossil fuels is taking carbon from a long-term store of the slow carbon cycle, and creating a huge input in the fast carbon cycle.
140
What is radiative/climate forcing?
The difference between insolation (sunlight) absorbed by the Earth and energy radiated back to space. Changes to Earth's climate system altering Earth's radiative equilibrium, forcing temps to rise or fall.
141
What is Earth's greenhouse effect and why is it important?
Natural balance between ingoing and outgoing radiation in the atmosphere. Without it Earth's temperature would be -18 degrees.
142
Explain the enhanced greenhouse effect and how it causes radiative forcing
Enhanced GH effect includes the impact of people. The extra gases cause radiative forcing by altering Earth's radiative equilibrium.
143
Give some adaptations to climate change
-Adapt food grown by diversifying crops that can tolerate warmer, wetter or frier conditions.
-Public health officials may need to manage new diseases that weren't previously an issue.
-Town planners will need to encourage development away from areas such as coastlines and river fronts.
144
Give some mitigations towards climate change
-International, national and regional policies to reduce carbon emissions.
-Changes in aviation
-Changes in rural use
-CCS and carbon suquestration.
145
What is the UN Convention on climate change 2015 and what was the aim?
-Added a target to stop global temps rising before they rise by 2 degrees. This can be met if cumulative carbon emissions don't exceed 1 trillion tonnes.
-However, 535 Gtc have already been emitted.
146
Describe the role of water and carbon
-An important link is the ability of water to transfer Co2.
-In people, carbon is stored in glucose and assists cellular respiration.
-Through respiration and decomposition, carbon is returned to the atmosphere as Co2.
147
Explain how climate change impacts water and carbon cycles
-Increased Co2 creates a warmer atmosphere which increases evaporation, leading to a positive feedback loop.
-Co2 levels rise, air temps rise, oceans warm leading to more evaporation.
148
Explain the marine phytoplankton feedback loop (water/carbon cycle)
Negative feedback loop:
-Use energy from the sun for photosynthesis.
-Release DMS (chemical that produces condensation over seas)
-Warmer temps lead to an increase in phytoplankton, causing an increase in clouds (DMS), which leads to a decreased temperature.
149
Explain the permafrost feedback loop (carbon cycle)
Positive feedback loop:
-Higher temps melt permafrost and organic matter in permafrost decomposes.
-Bacteria involved in decomposition produce Co2 and CH4 - increased GHGs.
150
Explain the sea ice melting feedback loop (carbon cycle)
Positive feedback loop:
-Ice reflects radiation
-As ice melts there is less reflection and more absorption by the land.
Has political and economic impacts (trade routes, settlements).
