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Overpopulation PowerPoint Presentation
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  1. Overpopulation

  2. Overpopulation • ~7 billion people • Many natural resources are nonrenewable • More people means: • 1) More forests removed • 2) More resources consumed • 3) More pollution

  3. The growing human population = pressure on Earth’s natural resources • Nonrenewable resources = used faster than they can form or be replenished: • Coal • Oil • Natural Gas MUST BE MANAGED EFFECTIVELY!!! • Renewable resources = cannot be used up or can replenish themselves over time : • Wind • Solar • Water Fossil fuels

  4. What are some Environmental issues Caused by human activity?

  5. G.H.E. is naturally good (it warms Earth) Problem: Excess heat trapped near the earth’s surface Fear: Climate patterns change, ice caps melt Main Cause: CO2 from burning of fossil fuels Solutions: Reduce use of fossil fuels, regrow trees, alternative energy sources The Greenhouse Effect

  6. What’s a Greenhouse? A Greenhouse is designed to trap heat so you can grow plants year round, even in cooler environments. heat Some heat escapes the greenhouse, but enough is trapped to keep the inside warm heat heat heat

  7. Some heat escapes into space heat Some heat naturally trapped by Earth’s atmosphere The Natural Greenhouse Effect is good! heat heat Earth The Atmosphere

  8. CO2, Methane, other greenhouse gases Earth

  9. Less heat escapes into space heat heat heat More heat trapped near Earth’s surface heat heat Excess CO2 in atmosphere Earth

  10. The Greenhouse Effect is naturally GOOD! Mars: No Greenhouse Effect Earth: Balanced Greenhouse Effect Venus: The Extreme Greenhouse Effect Little heat is trapped by the thin CO2 atmosphere. High temperatures can be around 20⁰F. Heat is trapped by the thick CO2 atmosphere. Temperatures reach 750⁰F. Average global temperature is 57⁰F.

  11. Acid Rain • Defined: Precipitation with a below normal pH • Cause: • Pollution from burning fossil fuels rises into the air • Effect: • Ecosystems more acidic • Kills plant and animal life • Biomagnification: toxins accumulate in living tissue higher up the food chain • Solutions: • Reduce fossil fuel usage • Add buffer (base) to waterways

  12. Biomagnification Acid rain Pesticide runoff Fertilizer runoff Mercury

  13. Nitric acid Sulfuric acid SO2 NO NO

  14. Ozone Layer Depletion Ozone Function: Block UV radiation from sun Problems: CFCs thinning the ozone layer CFCs common to coolants and foam production More UV radiation reaches the surface Effects: Crop damage, skin cancers, Eye damage Solution: Reduce CFCs, regrow trees UV UV Ozone layer blocks UV radiation from the sun Ozone layer CFCs

  15. Argh!!!!

  16. Reason: Burning of fossil fuels & industry Problems: Respiratory illness Ozone gas is poisonous Causes: Particulates rise into air and react with sunlight to make air pollution Solutions: Reduce use of fossil fuels alternative energy sources Plant trees The Smog and Ground-Level Ozone

  17. When is ozone good vs. bad? When Good When Bad When near the ground Where life exists • When 10-30 miles up in the atmosphere • It blocks UV radiation from the sun • Life doesn’t exist in the stratosphere

  18. Defined: Clearing of forested areas Reasons: High demand for wood Create farmland Problems: Species extinction Excess CO2 released Desertification: wind/rain carry soil away Solutions: Recycle Improved farming techniques Deforestation

  19. Non-native Species Introduction • Defined: Foreign organisms are introduced to a new habitat • Reason: • Pet industry, “free ride” organisms, pest control • Effects: • Foreign species outcompete native species • Food webs unbalanced • Decrease biodiversity • Economic damage • Solutions: • Laws preventing foreign goods into new countries Zebra mussels Kudzu vines

  20. Kobe Kuiz • CFCs are manmade chemical responsible for the destruction of _________________. • Which gas is a main contributor to the greenhouse effect? • Crop damage and cancers are caused by an excess amount of which type of energy? • Name the big three fossil fuels. • Which planet has excess temperatures because of a thick CO2 atmosphere? • Desert-like land is created as a result of which problem? • Where is ozone gas harmful to life? • Where is ozone gas helpful to life? • Food webs become unbalanced as a result of the introduction of which type of organisms? • Even though there may be space for people, why do those who study the environment consider humans to be overpopulated?