Water & Carbon Cycle Flashcards
Flows/ Transfers
Elements moving around the system
Closed System
When there are no inputs & outputs
System
Explains relationships within a unit.
Boundary
Edge of the system
Inputs
Elements entering the system
Outputs
Elements leaving the system
Stores
Elements being stored in the system
Flows/ Transfers
Elements moving around the system
Dynamic Equilibrium
A balance between inputs and outputs
Open System
When there are both inputs & outputs
Positive Feedback
When the effect of an action is amplified by other knock-on effects
Negative Feedback
When the effect of an action are nullified by it’s knock-on effects
Drainage Basin
the land drained by a river and its tributaries
Front
Where warm & cold air meet
Condensation
Gas to Liquid
Evaporation
Liquid to gas
Accumulation
Liquid to solid
Ablation
Solid to liquid
Sublimation
solid to gas
Deposition
gas to solid
Effect the rate of evaporation
- Amount of water
- Humidity of air
- Amount of sun
- Temperature of air
Precipitation
Rain from clouds after the water has condensed.
Infiltration
The rain being absorbed by permeable ground
Percolation
Movement of water through underground rocks
Water Table
The top of the groundwater
Groundwater
water stored in underground layers of soil and rock
Groundwater flow/baseflow
Water that is flowing underground
Through flow
movement of water through soil
Surface Storage
water held on the ground surface e.g. puddles
Stem Flow
Water transfer running down plants
Through fall
Water dripping from one leaf to another
Interception
Water being prevented from reaching the surface by trees or grass
Vegetation storage
water stored in vegetation
Transpiration
Evaporation of water from the leaves of a plant
Surface runoff (overland flow)
Water flowing on top of the ground
Peak discharge
the time when the river reaches its highest flow
Peak rainfall
The greatest amount of rainfall that falls in a storm
Rising Limb
The increase in river discharge as rainwater flows into the river
Falling limb
The decrease in river discharge as the river returns to its normal level
Lag time
Time between peak rainfall and peak discharge
Approach segment
Discharge before a rainstorm
Bankfull discharge
the amount of discharge at which the stream channel is full
Baseflow
Groundwater flow that feeds into rivers through river banks and river beds
Stormflow
The increase in stream velocity caused by a period of intense rainfall
Water Scarcity
not having access to enough clean water supplies
Water Stress
the condition that occurs when people don’t have enough clean fresh water to meet their everyday needs
physical scarcity
when there is not enough water to meet all demands
Economic Scarcity
water is present but lack of resources to meet water demands
Precipitation=
River flow/runoff (O) + Evapotranspiration (E) +/- Storage (S)
Inputs in the water cycle
precipitation
Outputs in the water cycle
Discharge, Transpiration, Evaporation
Stores in the water cycle
Vegetation, Surface storage, Channel, Soil Water, Groundwater
Processes in the water cycle
Interception, Stem flow, Through fall, Infiltration, Runoff, Through flow, Percolation, Groundwater flow
Subsystems of the Earth
- Atmosphere
- Lithosphere
- Hydrosphere = surface water
- Biosphere= plants & animals
- Cryosphere = ice
Percentage of freshwater on earth
2.5%
Isolated System
no interactions beyond the boundaries
Freshwater stores
- Ice caps (69.5%)
- Groundwater (30%)
- Lakes(0.25%)
- Soil Moisture (0.05%)
- Atmosphere (0.04%
- Swamps, mashes, wetlands (0.03%)
- Rivers (0.006%)
Atmosphere
Layer or set of layers of gases surrounding a planet, held in place by gravity.
Lithosphere
Contains all of the cold, hard, solid land of the crust, the semi-solid land underneath the crust and the liquid land near the centre of the Earth.
Hydrosphere
Contains all the solid, liquid and gaseous water of the Earth.
Biosphere
Contains all the planets living things
Cryosphere
Frozen water in the Earth’s system. There is an overlap between cryosphere and hydrosphere
ITCZ
Intertropical convergence zone
Hadley Cell
Large scale atmospheric convection cell at the equator
High Pressure weather
Predictable, clear sky
Low Pressure weather
Unpredictable, cloudy, rainy
Describe weather process at the equator & the tropics
- The equator has hot, low pressure weather
- As the water evaporates, it rises
- This water cools once it reaches the troposphere and condenses. It precipitates over the equator
- Once it has reached the troposphere it can no longer rise, so it spreads North and South towards the Tropics
- The air becomes colder and denser, and falls, creating high pressure and dry conditions around the tropics.
Describe pressure at the Ferrel Cell
- The warm air that moves North from the tropics picks up moisture
- Cold air from the poles meets the warm air
- Warm and cold air don’t mix
- The air masses meet at the polar front
- The cold forces the warm air to rise, creating low pressure
- The warm air cools as it rises, and condenses into clouds at Dew Point
- This takes place at 60 degrees North
- At the top of the troposphere air moves south and north towards the poles
- As it moves it cools, and becomes more dense
- It sinks over the poles, creating high pressure and no precipitation
- This cool,dry air then moves south towards 60 degreees North
Percentages of carbon in each sphere.
Lithosphere: 99.985% Hydrosphere: 0.0076% Pedosphere: 0.0031% Cryosphere: 0.00018% Atmosphere: 0.0015% Biosphere: 0.0012%
Global distribution of stores.
Cryosphere: Near the poles. Small areas around mountain ranges
Atmosphere: Highest in areas where it is autumn/winter when trees lose leaves. Java, Indonesia burning forests.
Hydrosphere: high in Atlantic areas because of warm currents.
Lithosphere: former USSR countries
Biosphere: forested areas, mainly rainforests around the equator
Pedosphere: areas in the high north with evergreen trees (boreal forests). Slower decomposition.
Factors driving change in the biosphere.
Respiration releasing CO2, but still only half of whats taken in by photosynthesis.
Decomposition of leaf litter releases carbon
Combustion from forest fires releasing a lot of carbon into atmosphere.
Factors driving change in the Cryosphere.
Reduced rate of decomposition so CO2 is stored. Believed to be 2.5 times the amount of carbon than in the atmosphere
Factors driving change in the Hydrosphere.
Ocean acidification happens due to large amounts of carbon reacting with the water to form carbonic acid.
Respiration of phytoplankton releases carbon from the hydrosphere.
Calcification of shells and coral
Compaction of plants and coral under sediment
Factors driving change in the Lithosphere.
Erosion and weathering
Volcanic activity
Tectonic uplift reveals sedimentary rock
How has the magnitude of stores changed over time?
Fast and slow carbon cycle.
Fast: diffusion, photosynthesis etc. Slow: compaction, weathering
Sinks & sources varying
Carbon sequestration
2 million years ago it was 180 ppm today its 400 ppm
How has the magnitude of stores varied over space?
Operates at 3 levels - plant, sere, continental/global
Boreal forest is a sere. High carbon content because of slow decomposition
Permafrost is continental. Where it’s melting in the Siberian Tundra, CO2 is being released
What are the natural variations causing change in the carbon cycle?
Cold temperatures
Hot temperatures
Volcanic Activity
Wildfires
How do humans impact the carbon cycle over time?
Agriculture
Hydrocarbons
Urbanisation
Deforestation
How does deforestation impact the carbon cycle?
Absorption reduced. 13 million ha cut down every year. 20-30% of all CO2 emissions. From sink to source.
How does urbanisation impact the carbon cycle?
Important stores replaced. Urban pop to reach 60% by 2030. Big impact on small cycles. 97% of CO2. Cement: 2.5-5% of emissions
How do hydrocarbons impact the carbon cycle?
Increase since Industrial Revolution. China, USA and INdia biggest consumers. Caused 78% of increase. responsible for 87% of emissions.
How does agriculture impact the carbon cycle?
Movement to meat diets; animal emission up 11%. Cattle in the US responsible for 20% of their methane. Rice demand increase, methane up 40%.
How do wildfires impact the carbon cycle?
Noticeable spike in emissions. Sink to source.
How does volcanic activity impact the carbon cycle?
130-180 million tonnes of carbon into atmosphere every year.
How do hot temperatures impact the carbon cycle?
More CO2 every 100,000 years. Melting of permafrost, releases CO2 and Methane
How do cold temperatures impact the carbon cycle?
Low CO2 every 100,000 years. less transfer into pedosphere, less flow into hydrosphere. Less decomposition and forest cover. More weathering