Demonstrate Understanding of Carbon Cycling

Science A.S. 1.14

Carbon

• Widely distributed in nature• Found in stars, planets,

comets• Diamond, graphite and

compounds (many vital for life)– CO2 (atmosphere and

dissolved in water)– Carbonates (rocks like

limestone)– Hydrocarbons (methane,

coal, oil and plastics)

Carbon CycleGame

Addition of Carbon

Natural

• Respiration (animal/ plant)

• Decay

• Volcanic activity

Anthropogenic (man made)

• Combustion

Respiration

• Conversion of “fuel” into energy by “burning” with oxygen

• Plants and animals do this

• They use the energy for life processes

• C6H12O6 + 6O2 → 6CO2 + 6H2O + energy

Greenhouse gases

http://www.ucar.edu/learn/1_1_1.htm

Decay• Animals and plants are made of carbon.

• When they die decomposing microbes break them down to produce energy.

• If oxygen is present the carbon is recycled as carbon dioxide.

• If no oxygen is present

methane is produced.

Decay video

http://www.topnews.in/usa/why-tectonic-plates-move-way-they-do-24873

Volcanic activity

• Carbon can be locked away for a long time as rock.

• It is returned to the atmosphere via volcanic eruptions.

Volcanic eruptions release CO2

http://www.teara.govt.nz/en/volcanoes/2/2

Volcanic Activity

• Volcanic eruptions release water vapor, carbon dioxide and sulfur dioxide into the atmosphere.

• 1986 a large leakage of naturally sequestered carbon dioxide rose from Lake Nyos in Cameroon and asphyxiated 1,700 people.

• Long term process for CO2 addition.

Combustion• Fossil fuel + 6O2 → 6CO2 + 6H2O + energy

• Complete

combustion

of hydrocarbons

produces CO2Fossil fuel burning

atmosphericCO2

http://nirantaradrusti.wordpress.com/2010/01/15/greenhouse-effect/

Breathing earth

West coast logging

Removal of Carbon

• May be long or short term carbon “sinks”

Natural• Photosynthesis (s)• Dissolving in oceans (s)• Formation of rock (l)Anthropogenic• Scrubbers (l/s)• Nanotube filters (s)

Carbon dioxide and the oceans

http://www.niwa.co.nz/__data/assets/image/0006/49443/gas2_large.jpg

Areas of Photosynthesis

Photosynthesis

• 6CO2 + 6H2O sunlight C6H12O6 + 6O2

• Green plants use the Sun’s energy to convert carbon dioxide and water into food.• Deforestation impacts on photosynthesis.•Phytoplankton undertake most photosynthesis.

Plankton capture carbon dioxide and form limestone

http://www.pmel.noaa.gov/co2/OA/OA1.jpg

Green machine

Dissolving in Oceans

• Carbon dioxide dissolves in water to produce acid.

• The decrease in pH will be bad for coral and shellfish.

• Absorption of CO2 by the oceans helps lessen the climatic effects of man’s emissions.

CO2 + H2O CO32- + 2H+

CO32- + Ca2+ CaCO3 (increasing acid breaks down shells)

Forming Rock

• CO2 reacts with metal oxides to produce stable carbonates (limestone)

• This process takes ages!

• The carbon can be “locked away” for a long time.

• Carbon can also be stored as coal.

Pancake rocks Caves

http://www.easytickets.com.sg/Honeymoon%20Packages/New/Pages/NZ/NZ%20Romance%20in%20the%20South.html

Limestone formations• Limestone is a

sedimentary rock made from shells.

• Water dissolves Limestone producing sinkholes and caves.

• calcium carbonate formations of stalactites, stalagmites are common.

Harwood’s Hole

Carbon Capture (sequestration)• Stopping CO2 from entering the

atmosphere (costly)Filters• Carbon nanotubes are

1/50,000th of the width of a human hair.

• They are made into filters to capture CO2 from industrial chimneys.

Geological• CO2 is injected into older oil fields

to extract more oil. • It could be trapped for millions of

years. • Cement production also captures

CO2

The global carbon cycle involves the earth's atmosphere, fossil fuels, the oceans, and the vegetation and soils of the earth's terrestrial ecosystems [Figure 2].