Water And Carbon Cycle Flashcards
What are geographical systems (cycles)
Hydrological cycle
Carbon cycle
Ecosystems
Oceanic circulation
Atmospheric circulation
What’s an ecosystem
An area with similar characteristics like vegetation across in, made up of biotic and abiotic features that are interdependent
What’s a biome
Area with similar climate and landscape where similar animals and plants live
What are the three classifications of systems
Isolated system - no flow of matter or energy (theoretical)
Closed systems - flow of energy but not matter. E.g. water and carbon cycles.
Open system - flow of energy and matter. E.g. the earth.
What is a cascading system
A system interested in the flow of matter and / or energy and understanding the processes that cause this movement.
What’s a control system
A system that can be manipulated by humans
What are inputs in the water cycle
. Precipitation
. Autumn leaf fall
. Seeds carried by the wind
What are outputs in the water cycle
. Plants
. Evaporation
. Seed dispersal
What are stores/ components in the water cycle
. Water
. Soil
. Water soaking through rocks/ soil
What are flows and transfers in the water cycle
. Photosynthesis
. Infiltration
. Transpiration
Albedo negative feedback loop
○ Surface temperature increases
○ Increased evaporation from oceans
○ Increased low clouds in the atmosphere
○ Increased earth’s albedo
○ Decreased surface temperature (slightly)
○ Decreased evaporation from oceans
○ Decreased low clouds in the atmosphere
○ Earth’s albedo decreases
Define negative feedback
System acts by lessening the effects of the original change. Holds system near or at equilibrium
Define positive feedback
Where a change causes a further effect (snowball) accelerating the changeable from equilibrium
Positive feedback example
○ temperatures warm
○ sea ice melts, and shrinks
○ dark ocean water has a low albedo and absorbs more solar radiation
○ temperatures warm further still
○ sea ice melts more
○ temperatures warm further
How Are models useful to geographers
○ very visual
○ help to simplify complex data/ theory
○ simplifications provide a starting point
○ help predict and describe sequences
○ shows interrelated components
How much of the earth’s total water is fresh water, and how much is oceans
Oceans (saline) water - 96.5% of the earth’s total water
Fresh water - 2.5%
Other saline water - 0.9%
Why isn’t salt water useful
○ can’t drink the water
○ can’t use salt water in machinery
Fresh water makes up 2.5% of the Earth’s total water, and how much of this is locked up in ice caps and glaciers
68.7%
(30% is groundwater, and 1.2% is surface and other freshwater)
Describe Oceanic water
. Problems
Dominant amount of available water.
About 1,320,000,000 km^3 of water.
But it’s salty so can’t be used, can’t be drank or used in machinery
Describe Crysophere water
Portion of earth’s water where water is solid, like sea ice, ice sheets, permafrost, alpine glaciers, and ice caps.
Contains 68-70% of the earth’s fresh water.
Water is hard to use as it’s trapped and locked up.
Describe Terrestrial water
Surface water, ground water, soild water, biological water.
There’s no much of it tho
Describe Atmospheric water
0.001% of earth water is atmospheric water (water vapour)
It’s difficult to obtain as it’s gas.
There are low amounts of water in the atmosphere because most of the water I in clouds which rain it back down (water cycle)
Define abstraction
Humans taking water out of natural sources
Where’s saline water stores other than oceans
In saline aquifers where the sea water has infiltrated rocks
What is the water cycle?
The continuous movement of water between the atmosphere, land, and oceans through processes like evaporation, condensation, and precipitation.
What are the main stores in the water cycle?
- Oceans (97%)
- Cryosphere (ice and glaciers)
- Groundwater
- Atmosphere
- Biosphere (plants and animals)
What are the key flows in the water cycle?
- Evaporation
- Condensation
- Precipitation
- Transpiration
- Infiltration
- Percolation
- Surface runoff
- Groundwater flow
What is a drainage basin?
An area of land drained by a river and its tributaries, separated by a watershed.
What factors affect the water cycle?
- Deforestation (reduces transpiration and interception)
- Urbanisation (increases surface runoff)
- Farming (alters infiltration rates)
- Climate change (affects precipitation patterns)
What is the carbon cycle?
The movement of carbon between the atmosphere, biosphere, lithosphere, and hydrosphere.
What are the main stores of carbon?
- Atmosphere (as CO₂ and methane)
- Oceans (dissolved CO₂)
- Biosphere (living organisms)
- Lithosphere (fossil fuels, rocks)
What are the key flows in the carbon cycle?
- Photosynthesis (absorbs CO₂)
- Respiration (releases CO₂)
- Decomposition (releases CO₂ and methane)
- Combustion (burning fossil fuels)
- Weathering (slow carbon release)
- Volcanic eruptions (release CO₂ from the lithosphere)
What is the carbon budget?
The balance between carbon inputs (e.g., respiration, combustion) and outputs (e.g., photosynthesis, sequestration).
What factors affect the carbon cycle?
- Deforestation (reduces carbon absorption)
- Burning fossil fuels (increases atmospheric CO₂)
- Ocean acidification (due to excess CO₂ absorption)
What is a key case study in the water cycle?
Amazon Rainforest: High humidity and rapid transpiration; deforestation reduces interception, increasing runoff.
What is a key case study in the carbon cycle?
Arctic Tundra: Permafrost melting releases trapped methane and CO₂; cold conditions limit decomposition rates.
What is dynamic equilibrium?
The balance between inputs and outputs in a system.
What is positive feedback?
A process that amplifies change.
What is negative feedback?
A process that counteracts change to restore balance.
What is carbon sequestration?
The process of capturing and storing atmospheric CO₂.
How does the cryosphere control the climate?
Snow and ice have a high albedo so reflect heat from the sun, regulating temperatures. Polar regions are some of the most sensitive to climate shifts
What are glaciers and how do they form?
An accumulation of ice and snow that slowly flows over land.
Snow remains in the same area all year round. Enough snow accumulates to form ice, new layers of snow form each year, and compress. Glaciers take hundreds of years to form.
What are alpine glaciers?
Frozen rivers of ice
What is permafrost?
Soil, sand, sediment, or rock the remains at or below 0°c for at least 2 years. (Defined solely by temperature, not water content)
What is sea ice?
Frozen sea water that floats on the ocean surface
Describe the features of a closed system
. Physical system
. Where a collection of components interacts through a system of transfers
. Flow of energy but no flow of matter across the boundaries of the system
. e.g. hydrological system
. A theoretical system
Explain negative feedback in relation to the water cycle
. A change causes another change that counteracts it, maintaining dynamic equilibrium
. Seen as a positive thing by humans
. E.g
Global warming temps increase, increasing water evaporation, condenses to clouds, higher albedo reflecting sun’s insolation, cools earth back down.
What significance do icecaps and glaciers play in global water stores?
. Only 2.5% of earth’s water is fresh, 95.5% is saline, which isn’t useful
. Ice caps and glaciers store 68% of the earth’s fresh water, so it’s locked up and hard to access (geographical, unuseful, as not many live where glaciers are)
. Greenland icecap is not a useful water source but is useful for climate reg.
. They grow and shrink seasonally
. When they melt it’s easy to get water
Residence time in water cycle stores
The length of time water stays in each store varies
Oceans - up to 4000 years
Groundwater - up to 1000 tears
Atmosphere - 10 days
Etc.
Glaciers flowing down hill
. When the glacier flows downhill, not the while glacier moves, just some
. Glaciers can have a residence time of several thousand years
. On a mountain, the top halt of the glacier is called the zone of accumulation (where the glacier grows)
. The bottom half is called the zone of ablation (glaciers melting)
. (Split by the equilibrium line)
What is carving ?
. When the snout of the glacier breaks off and form icebergs.
What factors are causing sea level rise?
- thermal expansion is responsible for 80% of sea level rise
- Glaciers melting into the sea is causing sea level rise ( causes 20% of sea level rise
- the fresh water from glaciers melting into the sea is changing the salinity, this is changing ocean current
What is the global average atmospheric pressure?
. 1 bar / 1000 milli bars
. There isn’t a massive difference in high and low pressure as the atmosphere can’t support big pressure differences (really low pressure = 980 millibars
Describe the sun’s rays causing air to rise, etc. And clouds.
- At the equator, the sun’s isolation is concentrated over a smaller area, and rays have to pass through less atmosphere
(hotter) - Hot air rises (heated by the sums rays) -> low pressure
(When gravity pulls atmosphere/ air down = dense/ high pressure) - Air rises and cools (as it cools the gas particles become smaller)
- As it gets higher up, air particels retract faster than water vapour, so the particles become saturated and can’t hold all the water vapour
- The water vapour condenses on condensation nucli (e.g. particles of dust, etc.) Forming clouds/condensing and raining)
What’s the point where clouds start to form called ?
Dew point
Describe the global circulation model?
Suns rays are concentrated at the equator, causing air to rise, and as it rises, it creates low pressure
As the air rises, wind moves it out, it cools and sinks -> Hadley cell
The same happens in the polar regions (although the around isn’t heated much still does is proportion to the air around, so rises slightly -> polar cell
The ferrell cell is in inbetween the two and is caused by friction.
What are inputs into glaciers ?
INPUTS
- precipitation
- deposition (water vapour freezing to the glacier)
- rockfall
- avalanche
What are outputs from glaciers?
OUTPUTS
- melting
- carving
- sublimation
- evaporation
Explain the role of the cryospheric change in the water cycle
The cryosphere contains 68-70% of the earths fresh water and is the frozen water in the earth that is locked up. This can either advance (grow) or retreat (melt).
If there is less water locked up in the cryosphere, then there is more water in the water cycle, which could lead to more rain/ precipitation and surface runoff to oceans and ecstatic sea level rise and more flooding.
However, if there is more water locked up in the cryosphere, there is less rain, less surface runoff, etc. Into oceans leading to ecstatic fall in sea level.
Explain the role of cryospheric change in the water cycle.
A01- • Cryospheric change has a regulatory role in sea levels (1). • The cryosphere is a major store of water (1). • In a period of cooling (glacial period) the cryosphere will grow in size (1). This is because the water cycle is slowed considerably as the ice restricts the return of the water to the sea and ocean (d). • In a period of warming the cryosphere will add water to the cycle (1). As the water cycle restarts more of the ice melts and retums water to the sea (d). • This increased the size of ocean store causing sea levels to rise through increased volumes of water (1) and thermal expansion (d). • Consideration of changes in permafrost is also valid (1).
No additional credit for straight reversals
What is the regulatory role of cryospheric change in sea levels?
Cryospheric change has a regulatory role in sea levels.
What is the cryosphere a major store of?
The cryosphere is a major store of water.
What occurs to the cryosphere during a glacial period?
The cryosphere will grow in size.
Why does the water cycle slow during a glacial period?
The ice restricts the return of the water to the sea and ocean.
What happens to the cryosphere during a warming period?
The cryosphere will add water to the cycle.
What is the effect of melting ice on the water cycle during warming?
More of the ice melts and returns water to the sea.
What causes sea levels to rise during warming?
Increased volumes of water due to less water locked up in the cryosphere and thermal expansion.
What is the cryosphere a major store of?
The cryosphere is a major store of water. Containing 68% of earth’s fresh water.
What occurs to the cryosphere during a glacial period?
The cryosphere will grow in size, as temperatures are colder, so glaciers and ice sheets grow/ accumulate.
Why does the water cycle slow during a glacial period?
The ice restricts the return of the water to the sea and ocean. And more water is locked up in the cryosphere, e.g., in glaciers and ice sheets se there is less in the water cycle.
What happens to the cryosphere during a warming period?
The cryosphere will add water to the cycle due to melting of e.g. glaciers.
How is hail formed ?
It is formed when snow melts as it falls through warm air and is formed to rise up, then freezes and falls as frozen droplets.
What ways do humans impact the hydrological cycle?
**Urbanization: **Increases surface runoff, reduces infiltration, and alters river discharge.
Deforestation: Reduces interception, infiltration, and evapotranspiration, leading to drier conditions and soil erosion.
Agriculture: Irrigation depletes water sources, soil compaction reduces infiltration, and deforestation for farming disrupts local water cycles.
Water Abstraction: Over-extraction lowers water tables, causing land subsidence and reduced groundwater recharge.
These activities alter water flows, storage, and availability, increasing risks of flooding, drought, and ecosystem disruption.
Describe flows and stores in the water cycle (diagram)
How does vegetation cover influence surface runoff?
Vegetation reduces surface runoff by increasing interception and slowing the movement of water to the ground. In contrast, bare soil has high initial infiltration, which declines as upper soil layers become saturated.
How does soil porosity affect infiltration and surface runoff?
Higher soil porosity increases infiltration and decreases surface runoff. Large pore spaces allow more water to enter the soil, while smaller pores restrict infiltration.
How does raindrop size influence infiltration?
Larger raindrops (common in intense storms) can exceed soil pore space capacity, reducing infiltration and increasing surface runoff.
How does slope angle affect infiltration?
Steeper slopes decrease infiltration and increase overland flow because water moves quickly. Gentler slopes allow water to remain on the surface longer, increasing infiltration.
What happens with the sun’s rays at the equator?
- At the equator of the sun’s rays are concentrated in a smaller area so it’s hotter, also the sun’s rays only have to pass through a small amount of atmosphere.
- The hot air rises heated by the sun’s rays, creating low pressure as the atmosphere is moved up.
- As the air rises and gets less dense and causes gas particles to become smaller, higher up the error tracks faster than the water vapour particles so
(as the air rises, it causes contracts in the water vapour condenses) - Air particles become saturated with the water vapour, and they can’t hold it all, and water vapour condenses on condensation nuclei.
What is the Greenland icesheet?
A large-scale global water store that contains 8% of the earth’s fresh water.
What would happen if the Greenland ice sheet melted?
Sea level would rise by 7.2 meters
When does glacial melting happen every year?
It happens in the summer every year but scientists have discovered it starting to happen earlier every year
What happens to glacias and ice sheets in the winter
The ice sheet grows in the winter (accumulation).
However, milder winters have led to reduced snowfall and less winter accumulation impacting albedo
What effect on the ocean will the Greenland icesheet melting have?
If the Greenland ice sheet melts a fast rate it will create layer of fresh ocean water which will press down the top of the dense saltwater also changes in salinity will modify ocean current circulation
How might atmospheric circulation be impacted by the Greenland ice sheet melting?
Current heat transfers between the Equator and the polls occur because of the extreme temperature difference between the two however the reduction in this temperature difference would reduce the force that drives a heat energy to the Poles affecting weather patterns and global precipitation patterns
How does deforestation affect the water cycle?
[4 marks]
Deforestation reduces interception, allowing more rainfall to reach the ground directly. This increases surface runoff and reduces infiltration. Evapotranspiration also decreases due to the removal of vegetation, leading to a reduction in atmospheric moisture. This can ultimately decrease local precipitation levels and alter the regional water balance.
How can human activity impact the carbon cycle?
[4 marks]
Burning fossil fuels for energy releases large amounts of carbon dioxide into the atmosphere, increasing the atmospheric carbon store. This disrupts the natural balance of the carbon cycle and contributes to the enhanced greenhouse effect. It also reduces the efficiency of carbon sequestration processes, such as ocean absorption, leading to long-term climate changes.
How can a storm event impact the water cycle?
[4 marks]
Storm events lead to intense precipitation over a short period, which increases surface runoff and reduces infiltration. Rivers respond quickly with a shorter lag time and higher peak discharge. The saturated ground can also lead to more overland flow and potential flooding, altering the natural movement of water within a drainage basin.
What is the effect of deforestation on the hydrological cycle?
Reduces interception and evapotranspiration, increases surface runoff and soil erosion, and reduces infiltration and groundwater recharge.
How does urbanisation impact the hydrological cycle?
Replaces permeable ground with impermeable surfaces, increases surface runoff and peak discharge in rivers, and reduces infiltration and increases flood risk.
What are the effects of agriculture on the hydrological cycle?
Soil compaction from machinery/livestock reduces infiltration, irrigation increases evapotranspiration and can deplete local water sources, and drainage systems speed up water flow, reducing lag time.
What is the impact of water abstraction on the hydrological cycle?
Lowers water tables and reduces base flow in rivers, and can lead to drying of wetlands and aquifer depletion.
How does dam and reservoir construction alter the hydrological cycle?
Alters natural river flow and stores water artificially, increases evaporation from surface water bodies, and reduces downstream discharge and sediment transport.
What are the effects of human-induced climate change on the hydrological cycle?
Alters patterns of precipitation and evapotranspiration, increases frequency of extreme weather events, and can change snowmelt timing and intensity, affecting river regimes.
What happens to water during glacial periods?
(Cryospheric water stores)
More water is stored in ice sheets and glaciers on land. Sea levels drop as water is locked in the cryosphere (solid ice).
What occurs during interglacial periods?
(Cryospheric water stores)
Melting of ice releases water from the cryosphere into rivers, lakes, and oceans. Cryospheric stores decrease, causing eustatic sea level rise.
How has recent climate change affected the cryosphere?
Recent climate change has accelerated melting, decreasing the cryosphere’s size and contributing to rising sea levels.
What is transpiration?
Loss of water through stomata on leaves of a plant.
What is interception?
Water hitting plants and trees before it reaches the ground.
What is infiltration?
Water breaking the surface entering a permeable surface.
Define soil moisture utilisation.
As it warms, potential evapotranspiration exceeds precipitation. The water store is used up by plants.
What is a soil moisture deficit?
There is a lack of soil water. Plants may wilt or adapt to survive dry conditions.
Reading a storm hydrolograph
What does spaital mean when in exam questions ?
So when we talk about spatial differences, we’re looking at how something (like precipitation, population, carbon emissions, or river discharge) changes from place to place.
Example (Water and Carbon Cycles):
Spatial differences in precipitation could mean comparing rainfall in tropical rainforests vs. deserts.
Spatial differences in carbon storage could refer to how much carbon is stored in a rainforest compared to tundra or urban environments.
What causes spatial differences in a hydrograph?
○ differences in geology
○ relief
○ drainage basin shape and size
can cause spatial differences in a hydrograph.
How do differences in geology affect a hydrograph?
Permeable rocks increase percolation, reducing surface runoff. Less runoff lowers discharge and increases lag time.
Example: In areas with permeable rocks, the hydrograph may show a delayed peak discharge.
How do differences in relief impact runoff rates?
Steeper slopes increase runoff rates and reduce lag time.
Example: A steep slope will lead to a quicker rise in the hydrograph.
What is the effect of drainage basin shape on hydrographs?
Elongated basins have lower but longer peak discharge, as water from the furthest point takes longer to reach the river.
Example: An elongated basin will show a prolonged peak on the hydrograph.
Temporal differences in a hydrograph may be caused by… |
- Differences in the duration of rainfall
- Differences in the intensity of rainfall
- Snowmelt or glacial meltwater
- Seasonal changes in vegetation (e.g. more interception in summer)
- Human activity, such as land use changes or dam release
What is bankfull?
The maximum discharge that a river channel is capable of carrying without flooding.
What is baseflow?
The normal day-to-day discharge of a river, caused by slow-moving soil throughflow and groundwater seeping into the river channel.
What is discharge?
The amount of water in a river flowing past a particular point, expressed as cumecs (m³/s).
What is lag time?
The time between peak rainfall and peak discharge.
What is peak discharge?
The point on a flood hydrograph when river discharge is at its greatest.
What is stormflow?
Discharge resulting from a storm, including overland flow, throughflow, and groundwater flow.
What is a storm hydrograph?
A graph showing river discharge over time during and after a storm event.
How does a drainage basin’s shape, size, and characteristics affect a hydrograph? |
- Larger drainage basins = more potential discharge, leading to higher peak discharge.
- Smaller basins respond more quickly = flashier hydrograph.
- Steeper slopes = faster surface runoff, less infiltration = short lag time and high peak discharge.
- Thick vegetation = more interception and slower runoff = lower discharge and flatter hydrograph.
- Basin shape: Elongated basins spread out water flow = lower, longer peak. Circular basins concentrate flow = flashier hydrograph.
How do you find the discharge of a river ?
Multiply the velocity of the river by the cross sectional area
What is it called when rivers don’t flow all year round?
Ephemeral
How does agriculture affect the water cycle?
Farmers influence the local water cycle through irrigation and land drainage. Soil with vegetation increases infiltration and reduces runoff, but after harvest, vegetation is removed, increasing runoff.
How does urbanization affect the water cycle?
Urbanization replaces vegetation with impermeable surfaces, preventing infiltration and percolation, increasing surface runoff, and raising flood risk.
How does water abstraction affect the water cycle?
In places like the UK, water is being pumped from the ground faster than it’s replenished, leading to a sinking water table.
How does irrigation affect the water cycle?
It significantly impacts water sources and transfer processes. In the Middle East, ancient underground aquifers are being abstracted, risking depletion.
How does soil drainage affect the water cycle?
Draining peatlands lowers the water table, alters infiltration and evapotranspiration, and destroys vital carbon stores.
Why is the Amazon important for geoprecipitation patterns, and how does deforestation impact this?
The Amazon releases up to 20 billion tons of water into the atmosphere daily, playing a crucial role in geoprecipitation patterns. However, deforestation reduces this water release, which decreases atmospheric moisture and can impact rainfall.
