overpopulation ~7 billion people many natural resources are nonrenewable more people means: –1)...
TRANSCRIPT
Overpopulation• ~7 billion people• Many natural
resources are nonrenewable
• More people means:– 1) More forests
removed– 2) More resources
consumed– 3) More pollution
• Nonrenewable resources = used faster than they can form or be replenished:– Coal– Oil– Natural Gas
• Renewable resources = cannot be used up or can replenish themselves over time :– Wind– Solar– Water
Fossilfuels
The Greenhouse Effect• 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
What’s a Greenhouse?A Greenhouse is designed to trap heat so you can grow plants year round, even in cooler environments.
heat
heat
heat
heat
Some heat escapes the greenhouse, but enough is trapped to keep the inside warm
Earth
heat
heat
heat
Some heat escapes into space
Some heat naturally trapped by Earth’s atmosphere
The Natural Greenhouse Effect is good!
The Atmosphere
CO2, Methane, other greenhouse gases
Earth
heat
heat
heatheat
heat
Excess CO2 in atmosphere
Less heat escapes into space
More heat trapped near Earth’s surface
The Greenhouse Effect is naturally GOOD!
Mars: No Greenhouse Effect
Little heat is trapped by the thin CO2 atmosphere. High temperatures can be around 20⁰F.
Earth: Balanced Greenhouse Effect
Average global temperature is 57⁰F.
Venus: The Extreme Greenhouse Effect
Heat is trapped by the thick CO2 atmosphere. Temperatures reach 750⁰F.
• 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
Biomagnification
Acid rain
Pesticide runoff
Fertilizer runoff
Mercury
SO2
NO
NO
Nitric acid
Sulfuric acid
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
Ozone layer blocks UV radiation from the sunOzone layer
CFCs
UV
Argh!!!!
The Smog and Ground-Level Ozone• 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
When is ozone good vs. bad?
When Good
• When 10-30 miles up in the atmosphere
• It blocks UV radiation from the sun
• Life doesn’t exist in the stratosphere
When Bad
• When near the ground• Where life exists
Deforestation • 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
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
Kobe Kuiz1) CFCs are manmade chemical responsible for the destruction of
_________________.
2) Which gas is a main contributor to the greenhouse effect?
3) Crop damage and cancers are caused by an excess amount of which type of energy?
4) Name the big three fossil fuels.
5) Which planet has excess temperatures because of a thick CO2 atmosphere?
6) Desert-like land is created as a result of which problem?
7) Where is ozone gas harmful to life?
8) Where is ozone gas helpful to life?
9) Food webs become unbalanced as a result of the introduction of which type of organisms?
10) Even though there may be space for people, why do those who study the environment consider humans to be overpopulated?