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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) CO 2 (atmosphere and dissolved in water) Carbonates (rocks like limestone)
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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 Cycle Game
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
Volcanic activity • Carbon can be locked away for a long time as rock. • It is returned to the atmosphere via volcanic eruptions. http://www.topnews.in/usa/why-tectonic-plates-move-way-they-do-24873
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.
Fossil fuel burning atmosphericCO2 Combustion • Fossil fuel + 6O2 → 6CO2 + 6H2O + energy • Complete combustion of hydrocarbons produces CO2
Breathing earth http://nirantaradrusti.wordpress.com/2010/01/15/greenhouse-effect/
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
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 Green machine http://www.pmel.noaa.gov/co2/OA/OA1.jpg
CO2 + H2O CO32- + 2H+ CO32- + Ca2+ CaCO3 (increasing acid breaks down shells) 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.
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 Harwood’s Hole • Limestone is a sedimentary rock made from shells. • Water dissolves Limestone producing sinkholes and caves. • calcium carbonate formations of stalactites, stalagmites are common.
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].