Anthropogenic Sources of Climate Change

1. Anthropogenic Sources of Climate Change

2. Major Anthropogenic Sources CO2 Aerosols Cement manufacturing Land use Ozone depletion Animal agriculture Deforestation

3. Fossil Fuel combustion and other human activities emit 30 Gigatons of CO2 into the atmosphere annually • Natural processes emit 770 Gigatons of CO2 into the atmosphere annually • The 4% of CO2 emissions humans produce over a long period of time will inhibit Earth’s ability to radiate heat to the upper atmosphere CO2 emissions

4. Industrial Revolution Wikipedia | GNU Period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the socioeconomic and cultural conditions Introduction of steam power fuelled primarily by coal

5. Industrial Revolution Wikipedia | Public Domain Increased use of machinery powered by burning coal established dramatic increases in production capacity By 2005 global atmospheric concentrations of CO2 were 35% higher than they were before the Industrial Revolution

6. A colloid suspension of fine solid particles or liquid droplets in a gas Examples: Clouds Air pollution (smog) Reflect or absorb sunlight, which either cools or warms the atmosphere In general, scientists believe aerosols have acted to combat climate change What are Aerosols? Wikipedia | Public Domain

7. Wikipedia | Public Domain NASA Key Groups of Aerosols Wikipedia | Creative Commons NASA Wikipedia | Creative Commons NASA Sulfates Black Carbon Mineral Dust Organic Carbon Nitrates Sea Salt

8. Fossil fuel combustion • Biomass burning • Automobiles • Incinerators • Smelters • Power plants • Deforestation • Overgrazing • Dust • Cigarettes • Stoves • Fireplaces • Candles Sources of AnthropogenicAerosols FYI: 10% of aerosols are anthropogenic

9. Sources of Anthropogenic Aerosols • Produced in industrial areas • Eastern U.S. (New York, Pittsburgh) • Europe (Berlin, London) • Anthropogenic emissions have increased in recent decades with increase in urbanization and industrialization in Asia

10. Substance that sets and hardens independently & can bind other materials together • Crucial component in buildings and roads • No viable recycling potential Cement

11. Calcium Carbonate is a key ingredient of cement CaCO3 → CaO + CO2 Accounts for 5% of anthropogenic CO2 emissions 900 kg of CO2 is emitted for every 1000 kg of cement produced!! Cement Manufacturing Wikipedia | Creative Commons

12. Land Use NASA reports that “scientists estimate that between one-third and one-half of our planet's land surfaces have been transformed by human development” A large body of research has documented the major role of land use and land cover change with variability in climate

13. Urbanization Suburbanization Deforestation Irrigating desert land Damming rivers Resource extraction Wikipedia | GNU Human Use of Land

14. Active area of research … Thunderstorm frequency Change in water cycle Change in energy budget Wikipedia | Creative Commons Potential Effects

15. Ozone Cycle Wikipedia | Public Domain Ozone prevents harmful UV light from passing through Earth’s atmosphere

16. Ozone Depletion NASA accessed via Wikipedia Steady decline of 4% per decade of stratospheric ozone Springtime decrease in stratospheric ozone over polar regions (ozone hole)

17. Two separate depletion events observed since late 1970’s • In both cases, ozone is destroyed by a reaction with halocarbon refrigerants (CFC’s, freons, and halons) • CFC’s = Chlorofluorocarbons Image is a prediction of what would happen if CFC’s were not banned NASA accessed via Wikipedia

18. International treaty designed to phase out production of substances (CFC’s) believed to be responsible for ozone depletion Signed in 1987 by 46 countries If the protocol is followed, the ozone layer could recover by 2050 Montreal Protocol

19. Notice any trends?

20. (Globally) ruminant animals produce about 80 million metric tons of methane This represents 28% of the anthropogenic methane emissions Animal Agriculture Wikipedia | Public Domain

21. Removal of a forest where the land is converted to a non-forest use • Farms • Ranches • Urban use Deforestation Wikipedia | Public Domain Wikipedia | GNU

22. Plants use CO2 for photosynthesis CO2 + H2O + energy from sun  C6H12O6 + O2 Fewer plants leads to an increase in CO2 in the atmosphere Deforestation Wikipedia | Creative Commons

23. Current Research Says… Deforestation in the tropics accounts for nearly 20% of carbon emissions due to human activities Maintaining forests as carbon sinks will make a significant contribution to stabilizing atmospheric greenhouse gas concentrations