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Physical Geography A-Level > Water And Carbon Cycles > Flashcards

Water And Carbon Cycles Flashcards

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1
Q

What is the Definition of a System?

A

A simplified way of representing a complex process (usually with inputs, outputs, and transfers)

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2
Q

What is an open system?

A

A system that has inputs and outputs of matter and energy

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3
Q

What is a closed system?

A

A system that has inputs and outputs of energy, but not matter

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4
Q

What is an isolated system?

A

A system with no inputs or outputs of energy or matter

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5
Q

What is the only true isolated system?

A

The universe

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6
Q

Is the water cycle/carbon cycle an open or closed system?

A

Closed

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7
Q

Is a drainage basin an open or closed system?

A

Open

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8
Q

Outline the key differences between an open and closed system (4)

A
  • An open system has inputs and outputs of energy and matter
  • For example, a drainage basin has inputs and outputs of matter (water) and energy (solar radiation)
  • A closed system has inputs and outputs of energy but not matter
  • For example, the water cycle has inputs and outputs of energy (solar radiation), but not matter
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9
Q

What is transpiration?

A

The movement of water through the stem of a plant from roots to leaves (transfer)

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10
Q

What is precipitation?

A

The falling of water from the sky in any form e.g. snow, rain, hail (input)

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11
Q

What is evapotranspiration?

A

The movement of water up a plant, then evaporating from the leaves (input)

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12
Q

What is through-flow?

A

The movement of water through soil (transfer)

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13
Q

What is percolation?

A

Water flowing from soil to rock (transfer)

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14
Q

What is infiltration?

A

Water flowing from the surface into soil or a permeable layer (transfer)

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15
Q

What is dynamic equilibrium?

A

Where there is a balance between inputs and outputs

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16
Q

What is a positive feedback cycle?

A

Change amplifies change in inputs and outputs

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17
Q

What is a negative feedback loop?

A

Change nullifies change in inputs and outputs

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18
Q

Give an example of a positive feedback loop

A
  • Temperature increases
  • Ice cover decreases
  • Albedo rate decreases (reflectiveness)
  • Surface absorbtion increases
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19
Q

Give an example of a negative feedback loop

A
  • More carbon dioxide in the air
  • Temperature increases
  • Rates of photosynthesis increases
  • Less carbon dioxide in the air
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20
Q

What are the 5 subsystems of water?

A
  • Hydrosphere
  • Atmosphere
  • Cryosphere
  • Lithosphere
  • Biosphere
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21
Q

Which store has the highest % of water and what % does it hold?

A

Oceans - 96.5%

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22
Q

What % of water is fresh water?

A

2.5%

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23
Q

What is latent heat?

A

Energy absorbed or released by a substance during a change in its physical state

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24
Q

Is latent heat absorbed or released as water turns from liquid to solid?

A

Released

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25
Q

Is latent heat released or absorbed when water turns from liquid to gas?

A

Absorbed

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26
Q

Is latent heat released or absorbed when water turns from solid to gas?

A

Absorbed

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27
Q

What are the 3 different scales of the water cycle?

A
  • Hill slope
  • Drainage basin
  • Global
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28
Q

What is temporal change?

A

The time period water is stored for

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29
Q

What is spatial change?

A

How much water, and where it is stored

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30
Q

What are the 3 factors that affect the temporal and spatial change of water?

A
  1. Evaporation
  2. Condensation (and precipitation)
  3. Cryospheric processes
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31
Q

What 4 physical factors affect evaporation?

A
  1. Amounts of solar energy
  2. Availability of water
  3. Humidity
  4. Temperature
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32
Q

How does humidity affect rates of evapotranspiration?

A

The more humid the air - the closer it is to the saturation point - the slower the rate of evaporation

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33
Q

How does temperature affect the rate of evapotranspiration?

A

Warmer air can hold more water than cooler air

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34
Q

What is the dew point?

A

The temperature at which the air is cooled sufficiently to a point where it can no longer hold water

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35
Q

How are clouds formed? (4)

A
  • Heat from the sun evaporates water, moving it from the hydrosphere to the atmosphere
  • In the atmosphere, water vapour particles constantly move around each other and collide with aerosols
  • As the water vapour rises it cools to the dew point, and condenses onto aerosols
  • When the air becomes saturated and cannot hold any more water, clouds form, and eventually as water droplets group together they become heavy, and gravity pills them into raindrops
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36
Q

What are aerosols?

A

Tiny particles of salt and dust

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37
Q

Under what circumstances 2 can condensation occur?

A
  1. When the temperature of the air reduces to the dew point, but the volume remains constant
    - e.g. during night, heat is radiated out to space and the ground gets colder, cooling the air directly around it
  2. When the volume of air increases but there is no addition of heat
    - e.g. when air rises and expands in the lower pressure of the upper atmosphere
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38
Q

Name 3 ways precipitation can occur

A
  1. Frontal effect
  2. Orographic effect
  3. Conventional effect
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39
Q

What it the frontal effect?

A

When air of different temperatures and densities meet, the less dense warm air rises over the denser cold air

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40
Q

What is the orographic effect?

A

When air is forced to rise over hills

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41
Q

What is the conventional effect?

A

When localised warm surfaces heat the air above, which expands, becomes less dense and rises

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42
Q

What is accumulation?

A

Where the mass of an ice sheet increases over a year, as inputs exceed outputs (usually in the upper parts of the glacier)

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43
Q

What is ablation?

A

When more mass is lost that gained over a year, when outputs exceed inputs (usually in the lower parts of the glacier)

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44
Q

What is sublimation?

A

When water vapour condenses onto a surface that is below freezing sublimation occurs, as the water turns directly from gas to solid, forming hoar frost

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45
Q

What happens during a glacial period?

A

Accumulation exceeds ablation - sea level was approximately 120m lower than present - hydrological cycle interrupted

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46
Q

What happens during an interglacial period?

A

Ablation exceeds accumulation - hydrological cycle returns to the same as today

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47
Q

What is the water balance equation?

A

Precipitation (P) = discharge (Q) + evapotranspiration (E) +/- changes in storage (S)

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48
Q

What is a drainage basin?

A

The physical area of land drained by a particular river

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49
Q

What is watershed?

A

The physical boundary of a drainage basin

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50
Q

What is water surplus?

A

When precipitation is greater than potential evapotranspiration leading to a period of soil moisture recharge

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51
Q

What is water deficit?

A

When outputs of water are greater than precipitation

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52
Q

What is abstraction?

A

When water is taken from stores of water surplus (generally rural areas with high rates of precipitation) to areas of water deficit (generally urban areas where population density is high)

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53
Q

What is soil moisture utilisation?

A

When the water store is used by plants, as potential evapotranspiration exceeds precipitation

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54
Q

What is field capacity?

A

The level of soil moisture held in soil, after excess water has been drained away

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55
Q

What is river flow?

A

The volume of water passing a measured point at a given time

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56
Q

What is bank full?

A

The maximum discharge a river channel is capable of carrying without flooding

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57
Q

What is base flow?

A

The normal day to day discharge of a river

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58
Q

How is the base flow sourced?

A

Slow moving soil through flow and groundwater seep into a river channel

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59
Q

Name 7 Factors that Affect Runoff Variation

A
  1. Season
  2. Storm Conditions
  3. Vegetation Cover
  4. Soil Saturation levels
  5. Topography and Relief
  6. Agriculture
  7. Urban Land Use
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60
Q

In what 2 ways does agriculture affect runoff variation?

A
  1. In pastoral farming, animals will compact soil, making it impermeable and increasing the runoff
  2. Combiners will plough the soil, mixing it up, and increasing permeability, decreasing the runoff
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61
Q

Name 9 characteristics of a drainage basin that affects a Hydrograph

A
  1. Shape
  2. Size
  3. Topography/Relief
  4. Geology
  5. Drainage density
  6. Length and Intensity of rain period
  7. Snowfall
  8. Saturation of drainage basin
  9. Vegetation
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62
Q

How does shape affect a Hydrograph?

A
  • Circular drainage basins lead to more flashy hydrographs as water reaches the main channel at the same point
  • Elliptical/Elongated drainage basins lead to less flashy hydrographs as the water reaches the main channel at different points
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63
Q

How does size affect a Hydrograph?

A

Larger drainage basins have less flashy hydrographs but higher peak discharge

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64
Q

How does topography affect a Hydrograph?

A

Steeper drainage basins have more flashy hydrographs, as water reaches the main channel faster

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65
Q

How does geology affect a Hydrograph?

A

The more porous and permeable a rock is, the more subdued the hydrograph will be

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66
Q

How does drainage density affect a Hydrograph?

A

The more surface streams acting as tributaries a drainage basin has, the more likely there is to be a flashy hydrograph

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67
Q

How does snowfall affect a Hydrograph?

A

Likely to lead to a more subdued hydrograph, as the water must first melt before it can contribute to runoff

68
Q

How does the saturation of a drainage basin affect a Hydrograph?

A

If a drainage basin has already been saturated by antecedent rainfall, then further precipitation will not be able to infiltrate, which will lead to a more flashy hydrograph

69
Q

Name 2 human factors that affect runoff variation

A
  1. Farming practises
  2. Changing Land Use
  3. Abstraction
70
Q

How do farming practises change the water cycle?

A
  • Ploughing breaks up the soil and allows for greater infiltration which reduces runoff
  • Contour ploughing, where furrows are created that run down slope can act a small stream channels leading to greater peak discharge and flashier hydrographs
  • Sowing compacts the soil, which leads to greater runoff
  • Animals can compact the soil in pastoral farming, which increases runoff
  • Irrigation introduces water into the soil, which raises the water table, and makes the land more susceptible to flooding
  • Terracing on hillsides stops movement of water downhill and subdues hydrographs
71
Q

How does changing land use affect the water cycle?

A
  • Deforestation reduces interception rates which leads to greater soil erosion and leaching, which degrades water quality for future use
  • Afforestation increases interception rates resulting in greater interception and therefore less runoff
  • Urbanisation increases impermeable surfaces, leading to more runoff
72
Q

How does abstraction affect the water cycle?

A
  • Over abstraction leads to falling water tables which ultimately results in dry periods when precipitation is low e.g. during the summer
  • Over abstraction can also lead to salt water intrusion in aquifers near coastal areas which degrades ground water quality
73
Q

Give 3 natural factors that affect variation in the water cycle

A
  1. Storm events
  2. Seasonal changes
  3. Ecosystem changes
74
Q

How do storm events affect the water cycle over time?

A

More precipitation means there is a temporary spatial shift from the atmosphere to the hydrosphere

75
Q

How do seasonal changes affect the water cycle over time?

A

Constant temporary changes in height of the water table dependent on the season e.g. autumn and spring months receive greater rainfall than summer months

76
Q

How do ecosystem changes affect the water cycle over time?

A

The more vegetation there is in an ecosystem, the more water is lost to evapotranspiration before it reaches the river channel, reducing runoff and peak discharge

77
Q

What are the 5 subsystems of carbon?

A
  1. Lithosphere
  2. Atmosphere
  3. Biosphere
  4. Cryosphere
  5. Hydrosphere
78
Q

How much carbon is stored in the Lithosphere?

A
  • 100 million GtC in marine sediments and sedimentary rocks - over 99.9%
  • approx 4,100 GtC in fossil fuels - 0.004%
  • 1,500-1,600 GtC in humus
  • approx 250 GtC in Peat
79
Q

Name 2 inorganic deposits of carbon in the lithosphere

A
  1. Fossil Fuels (gas)
  2. Sedimentary rocks (limestone)
80
Q

Name 2 organic deposits of carbon in the lithosphere

A
  1. Humus
  2. Litter
81
Q

Give the 3 layers the hydrospheric store of carbon and the amount of carbon they store

A
  1. Euphotic zone (surface layer) - 900 GtC is exchange with the atmosphere
  2. Deep Ocean - approx 37,100 GtC in the form of dissolved inorganic carbon
  3. Organic matter - 30 GtC/Dissolved organic matter - 700 GtC
82
Q

How much carbon is stored in the oceans?

A

Between 37,000 and 40,000 - 0.04% of the Earth’s carbon

83
Q

Outline how marine sediment forms

A
  • When organisms die dead cells, shells and other parts sink into deep water
  • Their decay releases carbon dioxide into this deep water
  • Some material sinks to the bottom where it forms layers of carbon rich sediments
  • Over millions of years, chemical and physical processes turn these sediments into rock which can lock up carbon for millions of years, and store up to 100 million GtC of carbon
84
Q

How much carbon is stored in the atmosphere?

A
  • Between 720 GtC and 800 GtC is stored as dioxide
  • Carbon dioxide concentration is around 400ppm currently
85
Q

How much carbon is stored in the biosphere?

A

3,170 GtC

86
Q

Give the 4 main stores of carbon in the biosphere

A
  1. Living Vegetation
  2. Plant Litter
  3. Soil Hummus
  4. Peat
87
Q

Outline the specifics of carbon stored in living vegetation

A
  • 19% of Earth’s biosphere is stored in plants
  • The amount of carbon in biomass varies from between 35-65% of dry weight
  • 1/2 of the carbon in forests occur in high-latitutde forests e.g. boreal forest in Russia (25% of world’s forest carbon)
  • A little over 1/3 of the carbon in forests occur in low latitude forests e.g. Amazon basin (20% of the world’s forest carbon)
88
Q

How much carbon does humus store?

A
  • 950 GtC in inorganic stores e.g. carbon/carbonate materials (calcite, dolomite, gypsum)
  • 1,550 GtC in organic stores
  • 2,500 GtC overall
89
Q

What is humus?

A

Litter decomposition (thick brown or black substance that remains after most organic matter has been decomposed) which dispersed throughout the soil via earthworms

90
Q

What is the significance of humus?

A

In all forests, 69% of the carbon is stored in the soil

91
Q

What is peat?

A

An accumulation of partially decayed vegetation or organic matter that forms in wetlands

92
Q

How much carbon does peat store?

A

250 GtC

93
Q

How much carbon is stored in the Cryosphere?

A

Less than 0.01% - mostly decomposing plants and animals frozen in permafrost

94
Q

Name 8 carbon flows

A
  1. Photosynthesis (net sink)
  2. Respiration (net source)
  3. Digestion (net source)
  4. Combustion (net source)
  5. Decomposition (net source)
  6. Ocean welling (net sink)
  7. Weathering (net sink)
  8. Sequestration (net sink)
  9. Volcanic Activity (net source)
95
Q

Name the 5 carbon flows that are a part of the fast carbon cycle

A
  1. Photosynthesis
  2. Respiration
  3. Digestion
  4. Combustion
  5. Decomposition
96
Q

Name the 4 carbon flows that are a part of the slow carbon cycle

A
  1. Ocean pumps
  2. Weathering
  3. Sequestration
  4. Volcanic activity
97
Q

Name 3 flows that occur at an organism scale

A
  1. Respiration
  2. Photosynthesis
  3. Digestion
98
Q

Name 2 flows that occur at an ecosystem scale

A
  1. Combustion
  2. Decomposition
99
Q

Name 3 carbon transfers that occur on a continental scale

A
  1. Sequestration
  2. Volcanic activity
  3. Ocean pumps
100
Q

How does photosynthesis affect the carbon cycle?

A
  • Transfers carbon stored in the atmosphere to biomass
  • Uses the sun as energy to exchange carbon dioxide and water for glucose and oxygen
101
Q

How does respiration affect the carbon cycle?

A
  • Transfers carbon from living organisms to the atmosphere
  • Plants and animals break down glucose for energy releasing carbon dioxide and methane
102
Q

How does digestion affect the carbon cycle?

A
  • Transfers carbon from living organisms into the atmosphere
  • All animals release carbon in the form of methane from digestion
103
Q

How does combustion affect the carbon cycle?

A
  • Transfers carbon stored in biomass (e.g. trees, peat, etc.) to the atmosphere by burning
104
Q

How does decomposition affect the carbon cycle?

A
  • Transfers carbon from dead biomass to the atmosphere and the soil
  • After death, bacteria and fungi break organisms down to release methane and CO2
  • Some carbon is transferred to the soil in the form of humus
105
Q

What are the two oceanic pumps?

A
  1. Carbon Pump
  2. Biological Pump
106
Q

How do the ocean pumps affect the carbon cycle

A

Allows for greater storage of carbon in the hydrosphere, keeping it out of the atmosphere

107
Q

Outline the process of the oceanic carbon pump

A
  • CO2 dissolves into water
  • Cooler water is able to dissolve more CO2
  • Warm water in oceanic surface currents is carried from warm tropics to cold polar regions
  • Water is cooled making it dense enough to sink
  • Cold water travels along ocean floor to lower latitude
  • Cold water rises to surface where it warms and looses CO2 to the atmosphere
108
Q

Outline the process of the ocean biological pump?

A
  • Living things in the ocean move carbon from the atmosphere to surface waters and then eventually down into the deeper ocean and eventually into rocks
  • When organisms die their dead cells, shells and other parts sink into the deep water
  • Some material sinks to the bottom where it forms layers of carbon rich sediments
  • Over millions of years, chemical and physical processes turn these sediments into rocks, locking up carbon for millions of years to come
109
Q

How does weathering affect the carbon cycle?

A
  • Transfers carbon from the atmosphere into the hydrosphere and biosphere
110
Q

Outline the process of weathering in the carbon cycle

A
  • Atmospheric CO2 combines with rain to form acid rain
  • Acid reacts with unstable rocks releasing calcium ions
  • These ions are then washed into the ocean where calcium ions react with bicarbonate ions to form calcium carbonate
  • This is absorbed by corals, plankton, and shell-building creatures
  • When these animals die, layers of shell and skeletal remains are compressed on the ocean floor to form rocks like limestone and dolomite
111
Q

What is Carbon Sequestration?

A

Carbon Sequestration is the process of capturing and storing atmospheric carbon dioxide for a prolonged period of time. It can occur both naturally and artificially.

112
Q

What is Geological Sequestration?

A

Geological sequestration is when carbon is captured at the source of factory emissions, liquified and stored in depleted aquifers or oil and gas reserves

113
Q

What is Biological Sequestration?

A

Biological sequestration is when plants photosynthesise, taking in carbon dioxide and storing it

114
Q

How does volcanic activity affect the carbon cycle?

A
  • Transfers carbon from the lithosphere to the atmosphere
  • Sporadic eruption events directly emit carbon dioxide into the atmosphere and methane is released by fissures before an eruption
115
Q

Name 2 natural variations in the carbon cycle

A
  1. Wildfires
  2. Volcanoes
116
Q

How do wildfires affect the carbon cycle in the short term?

A
  • The transfer large quantities of carbon from biomass to the atmosphere
  • Loss of vegetation decreases photosynthesis, so less carbon is removed from the atmosphere
117
Q

How do wildfires affect the carbon cycle in the long term?

A
  • The increase in atmospheric carbon that are the results of wildfires leads to carbon fertilisation and greater plant growth
  • Depending on the amount and type of regrowth, fires can have a neutral effect on the amount of atmospheric carbon
118
Q

How does volcanic activity affect the carbon cycle in the short term?

A
  • Carbon stored within the earth as magma is released during volcanic eruptions - the majority of which enters the atmosphere as CO2
  • Recent eruptions impacts have only been limited to an ecosystem scale as they have released much less CO2 than human activities, however, there is potential for a very large eruption to disrupt the carbon cycle on a continental or global scale
119
Q

Name 5 human variations on the carbon cycle

A
  1. Fossil fuel extraction and use
  2. Farming practises
  3. Deforestation
  4. Changing land use
  5. Cement production
120
Q

How does fossil fuel extraction and use affect the carbon cycle?

A
  • The largest single contribution to atmospheric CO2 is the burning of fossil fuels
  • The process takes carbon from the lithosphere, a part of the slow carbon cycle, where it took millions of years to sequester and releases it into the fast cycle, in quantities far higher than natural cycles can process resulting in an atmospheric build of up of CO2
  • 36.8 GtC were released from fossil fuel emissions in 2023
121
Q

Give 4 ways farming practices affect the carbon cycle

A
  1. Ploughing
  2. Tractor emissions
  3. Livestock emissions - 14.5% of all anthropogenic emissions
  4. Rice Paddies - 10% of total agricultural emissions
122
Q

How does soil ploughing affect the carbon cycle?

A
  • Air mixes into ploughed soil
  • Soil microbial activity increases
  • Organic matter breaks down faster
  • More carbon is lost from soil into atmosphere
123
Q

How does deforestation affect the carbon cycle?

A
  • Slash and burn releases carbon stored in the biosphere into the atmosphere
  • Deforestation removes a natural carbon store, reduces soil carbon content, and decreases photosynthesis
  • HOWEVER, satellite imagery shows that overall, tree cover is increasing due to tree planting that is occurring in agricultural temperate regions e.g. China
124
Q

How does changing land use affect the carbon cycle?

A
  • Growing urbanisation reduces vegetation coverage as cities expand
  • This leads to decreased natural stores of carbon, and rates of photosynthesis
  • Urban structures consume more energy than traditional rural settlements
  • Urban construction materials increase the demands for cement
125
Q

How does cement production affect the carbon cycle?

A
  • Transfers carbon from the lithosphere to the atmosphere
  • Calcium carbonate is heated to produce limestone, releasing 900kg of CO2 for every 1000kg of cement
  • The fuel needed to reach the high processing temperatures contributes to the release of CO2
126
Q

What was the impact of the construction of The Three Gorges Dam on the Carbon Cycle?

A
  • Used 27.2 million cubic meters of concrete
  • Released 4.86 GtC into the atmosphere
127
Q

What is the carbon budget?

A
  • The difference between the inputs of carbon into a subsystem and the outputs of carbon from it
  • E.g. in the at mosphere, inputs of carbon come from sources like volcanic eruptions/burning fossil fuels and outputs from sources like photosynthesis/sequestration
  • The balance of inputs and outputs determine whether it acts as a carbon source or a carbon sink
128
Q

What have scientists determined our current carbon budget cannot exceed?

A

1000 GtC

129
Q

How much of the global carbon budget have we used since the industrial revolution?

A

515 GtC - 52% of our budget

130
Q

How does the changing carbon cycle affect land?

A
  • Encourages plant growth in a process known as carbon fertilisation which decrease CO2 in the atmosphere
  • Raises temperatures, which dries out forests and increases wild fire frequency which further contributes to increasing atmospheric CO2
  • Rising temperatures also melts permafrost, which further increases levels of atmospheric CO2
131
Q

How much carbon is stored in permafrost?

A

1,600-1,700 GtC

132
Q

Name 6 ways that a changing carbon budget affects the ocean?

A
  1. Ocean Acidification
  2. Ocean Warming
  3. Melting sea ice
  4. Sea level rise
  5. Salinity
133
Q

What % of all CO2 that has been released into the atmosphere is absorbed by the oceans?

A

30%

134
Q

What does dissolving carbon dioxide into the ocean create?

A

Carbonic Acid

135
Q

What does carbon dioxide have to react with in order to create carbonic acid?

A

carbonate ions

136
Q

What use to carbonate ions have?

A

They are required to create calcium carbonate shells

137
Q

Name 2 animal species require calcium carbonate shells

A
  1. Coral
  2. Planktonic species
138
Q

What impact will removing carbonate ions from the oceans have on coral and planktonic speices?

A

The animals will have thinner and more fragile shells as they are required to expend more energy to build their shells

139
Q

How has the pH of the ocean’s surface changed since the industrial revolution?

A

decreased 0.1 - a 30% change in acidity

140
Q

How are polar and sub-polar marine ecosystems projected to react to a further drop in acidity?

A

The water is projected to become corrosive to unprotected shells and skeletons of organisms

141
Q

How long ago was CO2 absorbed into the water that is now rising from the depths of the ocean?

A

30-50 years ago

142
Q

Name the positive feedback loop in ocean acidification that leads to more carbonate ions

A
  • More CO2 absorbed by the ocean
  • More carbonic acid produced
  • More calcium carbonate rocks dissolved
  • More carbonate ions produced
  • More CO2 absorbed by ocean
143
Q

How in what 2 ways does ocean warming decrease the population of phytoplankton?

A
  1. Phytoplankton grow better in cooler waters
  2. Phytoplankton require nutrient rich waters
    - Nutrients come from the bottom of the ocean
    - Warming surface temperatures puts a cap on ocean mixing
    - This prevents nutrients from coming to the surface
144
Q

What affect does lowering the abundance of phytoplankton have on the atmosphere?

A

Increases the amount of CO2 in the atmosphere, as it decreases the capacity that the ocean has as a biological sink

145
Q

How could increasing CO2 in the ocean lead to an increase in growth of phytoplankton?

A

Phytoplankton and other ocean plants that take carbon dioxide directly from the water will have greater access to CO2 leading to more photosynthesis

146
Q

How does warming oceans also kill coral reefs?

A

It kills symbiotic algae which coral needs in order to grow

147
Q

By how much as sea ice in the Artic retreated by in the last 35 years?

A

12.8% per decade

148
Q

What is the positive feedback loop that sea ice is a part of?

A
  • More heat
  • Sea ice melts
  • Reduced albedo + increased absorption of heat into water
  • More heat
  • More sea ice melting
149
Q

What 2 things does sea ice provide a unique habitat for?

A
  1. Polar Bears
  2. Algae
150
Q

How can melting sea ice affect the food chain?

A

Melting sea ice can lead to reduced amounts of algae which affects the entirety of the food chain

151
Q

Name 2 ways that increasing temperatures can lead to a decrease in salt concentration in the ocean?

A
  1. Leads to more precipitation which leads to higher river runoffs that eventually reach the ocean
  2. Leads to melting of the Greenland ice sheets.
152
Q

What does thermohaline refer to?

A

The temperature and salinity of the water

153
Q

What do the ocean currents determine?

A

The distribution of our heat and climate

154
Q

How does heat affect the density of water?

A
  • Warmer water is less dense and rises
  • Colder water is more dense and sinks
155
Q

Why does the concentration of salt increase when temperature increase?

A

More water from the ocean is evaporated, leading to higher salt content

156
Q

How much colder would Europe be without the gulf stream?

A

5-10 degrees

157
Q

How might a decrease in salinity stop the gulf stream?

A
  • Ice caps melting add fresh water
  • This makes the water less saline and by extension less dense
  • Therefore water will not sink, meaning there will be nothing pulling the gulf stream conveyer belt
158
Q

How does the changing carbon cycle affect the atmosphere?

A
  • Increasing levels of CO2 in the atmosphere due to human actions, leads to more heat being trapped, and contributes to the enhanced greenhouse effect
159
Q

How does water sustain life on earth?

A
  • Needed by all living creatures to sustain life
  • Farming for humans
  • Used in photosynthesis to sustain plant life
160
Q

How does carbon sustain life on earth?

A
  • Key component in all known life: 50% of all biomass
  • Crucial GHG in maintaining climate
  • Used in photosynthesis to sustain plant life
  • Oxygen produced in photosynthesis is crucial for respiration
161
Q

Give 3 impacts of Climate Change on life on earth

A
  1. Patterns of precipitation will chane
  2. Sea level rise
  3. Storm events will occur more frequently
162
Q

Give 2 mitigation strategies for climate change at an individual level

A
  1. Utilising electric or more fuel efficient cars
  2. Making their homes more energy efficient by installing double glazed windows
163
Q

Give 2 mitigation strategies for climate change at a local level

A
  1. Improved public transit facilities
  2. Creating more green spaces within towns and cities
164
Q

Give 2 mitigation strategies for climate change at a national level

A
  1. Carbon capture and storage (CCS) strategies (carbon sequestration)
  2. Reducing reliance on fossil fuels by subsidising and constructing renewable energy sources e.g. solar panels/wind turbines
165
Q

Give 2 mitigation strategies for climate change and an international level

A
  1. International treaties e.g. Kyoto Protocol and Paris Agreement (2015) where climate change was limited to 1.5 degrees
  2. Carbon credit schemes where countries and businesses are given limits on the amount of CO2 they can emit

Physical Geography A-Level (3 decks)

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