Water and Carbon

• How has changing land use changed the carbon cycle?

  Deforestation:

  - Trees are a sink so less will be absorbed, meaning more CO2 is in the atmosphere

  - Slash and burn

  - without trees land can dry up and become barren forests

  
  

  Urban growth:

  - Land changes from natural vegetation to built on

  - Transport and manufacturing industries have also increased carbon emissions
• How has combustion of fossil fuels changed the carbon cycle?

  - 90% of human created carbon has came from burning of fossil fuels

  - By burning them, it releases concentrated levels of CO2 to the atmosphere, thickening it causing temps to rise
• How does volcanic activity change the carbon cycle?

  - Eruptions release CO2 into the atmosphere which historically have been known to rise temps
• How has wild forest fires changed the carbon cycle?

  - Forests are known as a 'sink' therefore when burnt the CO2 is released back into the atmosphere
• How has farming practices changed the carbon cycle?

  - During the ploughing of soil, the soil layers are inverted with each other and air gets between them causing soil organic matter to decompose faster releasing CO2 to the atmosphere
• What is negative feedback?


  - Where the effects of an action are nullified by the secondary knock on effects
• What is positive feedback?


  - Where the effects of an action are amplified by secondary knock on effects
• Give an example of negative feedback in the water cycle?

  - Increased global temps

  - So increased evaporation rates

  - So more water vapour in atmosphere

  - Therefore cloud cover increases decreasing global temps
• Give an example of positive feedback in the water cycle?


  - Increased global temps

  - So increased evaporation rates

  - So more water vapour in atmosphere

  - Therefore tapping the suns rays which increases global temps
• Give an example of negative feedback in the carbon cycle?

  - Increase use of fossil fuels increases the CO2 in the atmosphere

  - Plants will thrive so increased growth

  - CO2 will decrease as more will be uptake through photosynthesis

  - The decreasing CO2 and less sun rays trapped means lower temps
• Give an example of positive feedback in the carbon cycle?


  - Global temps rise

  - In turn so does ocean temps

  - More CO2 is released into the atmosphere since it isn't dissolved by oceans because warmer oceans dissolve less CO2

  - This traps the suns rays, further increasing temps
• What is a system?


  - A group of interrelated parts including stores, flows, boundaries, inputs and outputs
• What is a closed system?

  - A system where energy can enter and leave but matter cannot
• What is an open system?

  - A system where both matter and energy can leave the system
• What are the major stores of water?

  - Oceanic water

  - Cryospheric water

  - Atmospheric water

  - Terrestrial water
• What is the largest store of water?

  Ocean
• What are the 6 spheres?

  - Atmosphere

  - Hydrosphere

  - Biosphere

  - Pedosphere

  - Cyosphere

  - Lithosphere
• Which store has the largest resistance time?

  Deep ground water - 10,000 years

  
  

  - Due to the rocks being permeable allows for percolation to occur, storing the water deeper underground making it harder to transfer
• Which store has the least resistance time?

  Soil water - 1/2 months

  
  

  - It has a small soil moisture budget therefore the store fills up extremely fast and can lead to overland flow
• What is terrestrial water?

  - Water held on/in the ground e.g. ponds, lakes, rivers

  
  

  - Ground water depending on how porous the rock is

  
  

  - Soil water
• Which type of cryospheric water raises sea levels when melted?

  Ice shelf
• What type of cyospheric water does not raise sea levels when melted?


  - Sea ice
• How does cryospheric change effect the water cycle?

  - Cyosphere is a major store of water

  
  

  - Warmer periods causes cryosphere to add to the water cycle as glaciers and ice shelfs melt, adding to the hydrosphere

  
  

  - In a period of cooling, the cryosphere grows as water cycle is slowed because ice restricts water
• Does water leave the hydrosphere cycle?

  No, it only gets transferred from one store to another
• What are the two types of lithosphere?

  - Oceanic lithosphere

  - Continental lithosphere
• Which sphere interacts with all other spheres?

  Biosphere - as life exists in air, water and ground
• How does photosynthesis transport carbon?

  - Plants use sunlight and carbon to produce carbohydrates e.g. glucose

  
  

  - In this process O2 is released into the atmosphere
• How does burial and compaction transport carbon?

  - When organic matter dies, it gets buried by sediment and is eventually compacted

  
  

  - This will then turn into hydro-carbons overtime which ae fossil fuels
• How does decomposition transport carbon?

  - When organisms die, they are consumed by decomposers e.g. bacteria

  
  

  - During this process CO2 is released from the bodies to the atmosphere

  
  

  - Organic matter can also pass into the soil and then be stored for hundreds of years
• How does weathering transport carbon?

  - The break down of rocks releases the CO2 stored within them

  
  

  - The rainfall then absorbs this carbon to create carbonic acidic acid

  
  

  - This eventually dissolves the rocks and this solution gets transported via the water cycle to oceans
• What are the major transports of carbon?

  - Volcanic eruptions: Carbon released from the lithosphere to the atmosphere during evaporation

  
  

  - Sinking: Carbon 'sinks' from oceans to deep ocean currents.

  
  

  - Photosynthesis: from atmosphere to plants

  
  

  - Respiration: from animals to atmosphere
• What are the major stores of carbon?

  Lithosphere - rocks

  
  

  Plants - takes up carbon through photosynthesis

  
  

  Atmosphere - any carbon released into the air

  
  

  Ocean surface - carbon sink

  
  

  Phytoplankton - tiny creatures in the sea that uptake carbon to crate their shells
• What is the largest store of carbon?

  Lithosphere
• What is a carbon sink?

  A store that absorbs more carbon than it releases
• What is a carbon source?

  A store that releases more carbon than it intakes
• How do storm events affect a local water cycle?

  - Increased precipitation exacerbates the soil store due to increased infiltration and interception which can lead to overland flow and flooding
• How can seasonal changes effect a small scale water cycle?

  Summer - evaporation increases, less rainfall means stores will deplete

  
  

  winter - freezing occurs, reducing infiltration and interception
• How does deforestation effect local scale water cycles?

  - Removing trees will reduce interception

  - So lower store of rainfall in tree roots

  - This surplus of rain water will then become overland flow and increase flooding as it enters the river too quickly
• How does urbanisation effect a local scale water cycle?

  - Reduces Greenland in our cities therefore increases the amount of impermeable surfaces, decreases infiltration via vegetation and could cause overland flow

  - Decreasing infiltration dries out the soil and make sit unsaturated
• How does irrigation effect local water scales?

  - Faming practices e.g. sprinklers can cause over watering of the soil making it too saturated meaning the soil water store becomes full increasing run off

  - However, soils covered in plants have higher interception rates therefore reduces run off.