VIEWS: 0 PAGES: 8 POSTED ON: 11/26/2011
The Carbon Cycle & Changes in Atmospheric Carbon Dioxide IB Biology – Topic 5.2 Carbon Crucial element to living organisms The term organic implies that carbon must be present Life on Earth is referred to as carbon-based life Where is carbon found? Carbohydrates, lipids, proteins, vitamins In the atmosphere (CO2) Lithosphere (rocks) Carbonates, fossil fuel Petroleum Gasoline, kerosene, plastics Carbon is constantly recycled Photosynthesis Plants take CO2 in These producers are eaten by consumers, which use the carbon In their bodies Cellular respiration All trophic levels & decomposers produce CO2 which is released back into the atmosphere Even plants Other sources of carbon dioxide Humans! Burning wood or non-renewable resources Petroleum products Volcanic activity Marine organisms can take carbon out of the water to make their shells Shells accumulate as sediments at the bottom of the ocean Trap carbon for millions of years in limestone Limestone is one of the main ingredients for cement Making cement carbon is released as CO2 The Carbon Cycle Changes … Ever since the industrial revolution (1800s), humans have produced increasing quantities of carbon dioxide Machines Factories Transportation Deforestation Burning wood (cooking, heating) all comes down to burning fossil fuels (coal It and oil) Rising CO2 levels NASA data on CO2 levels Over the decades, 375 human pollution has 370 365 produced enough 360 CO2 to raise its 355 CO 2 percentage in the concentration / ppm 350 345 atmosphere 340 335 Some suggest levels 330 have increased by 325 about 25% 320 1970 1975 1980 1985 1990 1995 2000 compared to pre- industrial revolution levels Why do CO2 levels fluctuate? Plants, phytoplankton, and photosynthetic bacteria are more active in the summer months Think about Chicago in the winter … do you see a lot of green? Therefore, more CO2 is taken out of the atmosphere during the summer months According to NASA data (previous slide), there has been a 19.4 % increase in the mean annual concentration of CO2 over the past 47 years.
Pages to are hidden for
"The Carbon Cycle _ Changes in Atmospheric Carbon"Please download to view full document