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Planetary boundaries - Coggle Diagram

- - - - If too few, may become extinct
      - Species interact, so entire communities may be extinct
  - - - Seed banks
      - Sperm banks
    - - Ivory
    - - Fishing
      - Logging
    - - Fertilisers
      - Pesticides
  - - - Ocean acidification
      - Rising temperatures
  - - - Normal - 1
      - Current - 100
      - Boundary - 10
- - - - Temperature is controlled by greenhouse gases
      - More CO2 = Higher temperatures
        
        Which affect
        
        Wind patterns
        
        Ocean currents
        
        Rainfall
        
        Precipitation
  - - - Warmer seas melt polar ice
      - Sea is less reflective than ice
        
        More heat is absorbed
        
        Warmer seas
    - - Increases sea level
      - Global temperature
      - Irreversible
  - - - Kyoto protocol
        
        1997
        
        84 countries
      - COP21
        
        Paris - 2015
        
        April 2016 - 174 countries
        
        Keep global temp, below 2.0*C
        
        Optimistically 1.5*C
        
        Limit greenhouse gas emissions
        
        To that can be naturally absorbed
        
        Richer countries help poor nations
        
        Adapt to climate change
        
        Switch to renewable energy
    - - Reduction of fossil fuels
      - Renewable resources
- - - - Absorbs UV light from the sun
        
        UV causes mutations in DNA
        
        Damage to living organisms
  - - - Causing a "hole"
      - Detected over antarctica
  - - - Manufacture and use of
        
        Chlorinated and brominated hydrocarbons
        
        Phased out
      - The only boundary avoided by deliberate action
  - - - From refrigerants
      - Aerosols
      - e.g. CFCs
- - - - DDT
      - PCBs
    - - 131I, 32P, 14C, 90Sr
    - - But required for solutions to many problems
        
        World food shortages
        
        Drug manufacture
        
        Cleaning up pollution
    - - Particles >100nm
      - Uses
        
        Coatings on products
        
        e.g. computer chips
        
        Medical
        
        e.g. early disease identification
    - - e.g. plastic beads
    - - Emission of toxic and long-lived substances
        
        Heavy metals
        
        Radioactive metals
        
        Synthetic organic pollutants
  - - - Reduced bird populations
  - - - Only a few have been assessed
- - - - Natural
        
        e.g. ash from volcanoes
      - Human activity
  - - - Effects are complex
      - Varies, not quantifiable
        
        Estimated to cause 800,000 premature deaths
        
        Per year
    - - Soot
        
        Absorbs heat
        
        Contributes to global warming
      - Sulphates
        
        Reflects heat
        
        Cooling effect
      - Diesel engine particles
        
        Inhaled and lodged into lungs
        
        Increase risk of lung cancer
        
        If small enough
        
        Can pass through blood capillaries
        
        Increasing risk of cardiovascular disease
  - - - Causes
        
        Coal power stations
        
        Wood burning stoves
        
        Heavy industry
      - Effects
        
        10% sunlight blocks
        
        Lowers
        
        Temperature
        
        Evaporation rates
        
        Rainfall
        
        Increases
        
        Floods
        
        Droughts
        
        Disrupting monsoons
    - - 1970s and 1980s
      - Linked to pollution (from)
        
        Europe
        
        America
      - Reduces moisture in air moving over Africa
    - - Mostly from burning felled trees
        
        After deforestation
      - Accumulates in atmosphere
        
        Noticeable over the poles
        
        Falls and darkens ice sheets
        
        Reflects less heat
        
        Melts more quickly
  - - - Hard to define safe limits
- - - - 61% is frozen
    - - Toxic ions + dust
    - - Desertification
      - Rivers may fail to reach the sea
      - Fisheries are destroyed
      - Loss of bodies of water
        
        More extreme temperature
        
        More arid
        
        e.g. drying of the Aral Sea
  - - - Longer lifespan
      - Irrigating crops
      - Daily life
    - - Draining wetlands
      - Deforestation
  - - - e.g. biofuels
- - - - Raising livestock
      - Farming
      - Biofuel crops
      - Urban development
  - - - Degrade the land
      - Production of biofuel crops + Crops for export
        
        May not be enough food produced for use
  - - - Crop growing
      - Human habitation
    - - More efficient crops grown
- - - - Decreases pH
        
        Forming carbonic acid
    - - Now at 8.03
      - H+ ions are 30x concentrated
  - - - Decrease in internal pH
        
        Enzyme-mediated reactions decrease
        
        Less photosynthesis
      - Les oxygen produced
      - Less CO2 removed
    - - e.g. corals, molluscs
        
        Cannot form shells in acidic water
        
        More susceptible to predators
  - - - Of aragonite
        
        A form of calcium carbonate
    - - Current levels close to boundary
      - Preventing increase in CO2
        
        Prevents permanent crossing
- - - - Uptake by plants is limited
        
        So, eutrophication
  - - - Run-off into bodies of water
        
        Algal blooms
        
        Anoxic zones
      - Acidification
        
        Excess CO2 dissolves in bodies of water
        
        Disruption of gas exchange in fish
        
        Softening of
        
        Shells of molluscs
        
        Exoskeletons of arthropods
  - - - Every year
      - Prevents disruption of global nitrogen cycle
      - Currently at 150million tonnes
- - - - May cause abrupt irreversible environmental change