5/28/2013

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Environmental Changes

1. Global Warming

2. Acid Rain

3. Ozone Depletion

4. Fertilizer Runoff

5. Loss of Biodiversity

Global Warming

• What is the Greenhouse Effect?

- a natural process

of heat absorption

by certain gases

in the atmosphere

to regulate Earth’s

temperature preventing

its escape into space

Gases act as a warming blanket

for the EarthWithout A Greenhouse Effect

Earth would be a big frozen ball, where no bacteria

could have developed and led to Life, and US!

57 F

0 F

Key Facts

• Increased gases due to Industrial Revolution

(growth of factories- machines)

• Records show: 1990’s hottest decade ever

recorded-Each year was among hottest 15

years since 1880

- Temp by 0.76°C (1.36°F)

- End of 21st century, temp will

4°C (7.2°F)

Enhanced Greenhouse Effect

“Trapped” Gases

• CO2burning fossil fuels

(coal, natural gas, oil)

deforestation

• Methaneanimal livestock, agriculture, fossil fuels, decay of organic wastes in landfills

•Nitrous oxidefertilizer use, industries

natural sources: oceans, soil

•Water vapornatural component of climate

•Ozone absorbs UV radiation

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Effects

• Increase in sea temperature (decrease

phytoplankton)

• Increase sea level (melting ice caps, warming water)

• Coastal flooding (hurricanes/droughts/flooding)

• Drier soil & more clouds (increased evaporation)

• Greater range of insects

What’s Wrong With

This Picture?

Rising Sea Levels To Endanger

Nuclear Power Future?

When Do You Send Greenhouse

Gases into the Air?

Whenever you ...

• Watch TV

• Use the Air Conditioner

• Turn on a Light

• Use a Hair Dryer

• Ride in a Car

• Play a Video Game

• Listen to a Stereo

• Wash or Dry Clothes

• Use a Dish Washer

• Microwave a Meal

All these

functions need

electricity that

comes from

power plants

that burn coal

& oil

What You Can Do!

1. Save electricity by burning less fuels(turn off lights, the television, and the computer when you are through with them)

2. Bike, Bus, or walk to school

3. Plant trees (Reforestation)(helps remove the CO2 from the air)

4. Recycle

(cans, bottles, plastic bags, and newspapers. This sends less trash to the landfill & save natural resources, like trees, oil, and elements such as aluminum)

5. Use Solar Energy Saving Appliances (stereos)

Solar

panels

Recycle

symbol

Energy

symbol

Air

compressed

car

Hybrid cars

Electric

windmills

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• Deforestation- The change of forested lands to non-forest uses. This is often cited as one of the major causes of the enhanced greenhouse effect for two reasons: 1) trees that are burned or decompose release carbon dioxide; and, 2) trees that are cut no longer remove carbon dioxide from the atmosphere.

http://epa.gov/climatechange/kids/global_warming_version2.html

Acid Rain

Key Facts

• Typical rain pH= 5-6 (carbonic acid)

Acid rain= 4

• Burning of fossil fuels such as power plants, factories, fire places, and cars release gases into air.

• Nitrogen oxide & sulfur dioxide react with water droplets from the clouds forming a weak acid

Acid Rain Formation

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Effects

1. Damage trees

- damage to coating (cuticle), leaves plant susceptible to injury, disease, & prevent photosynthesis

2. Increase soil acidity

- deplete soil minerals & release harmful substance (aluminum)

3. Increase acidity of lakes & streams

- cause deformities in egg development & elimination of species in an ecosystem

4. Building corrosion

- a chemical reaction (steel bridges, pipes, airplanes, buildings/limestone)

Acid precipitation had affects that

passed on up the food chain for

tree nesting birds

Cleopatra’s

needle

Trees affected by acid rain

Evidence of the Effects of

Acid Rain

Could the collapse of the Minnesota

bridge be from years of corrosion

from acid rain?

Aim

�To Preserve Natural Habitats

�Reduce Damage to Man-Made Structures

Efforts To Reduce

Sulfur Dioxide& Nitrogen Oxides

By the U.S. EPA

• Burn Less Fossil Fuels-Alternative Energy Sources (electricity, nuclear power, hydropower, wind energy, solar energy, batteries, natural gas)

• Use Smokestacks/Scrubbers (reduce release of SO2, NO2 in factories; burn natural gas instead)

• Liming (short term solution: add limestone to lakes to allow native populations to survive)

• Continue research studies (better understand

how to control air pollution & reduce it)

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Ozone Depletion

Key Facts

• Ozone layer

- a natural gas (O3) that absorbs the sun’s dangerous UV

light

• Good Up High - Bad Nearby

- closer to Earth damages plants, crops, smog, traps heat

- Farther from Earth protects from harmful UV rays

• Chlorofluorocarbons (CFCs)

- substances used in coolants, foaming agents, fire

extinguishers, solvents, pesticides, and aerosol propellants.

When sun’s rays release the chlorine atoms from CFCs, it

breaks down the ozone layer.

Effects

• Human Health- increase amounts of UVA reaching Earth’s surface (skin

cancer, cataracts, weakens immune system)

• Plants - affect plant structure/development/disrupt recycling of

nutrients

• Marine Ecosystems- kills phytoplankton, damage development & reproduction

of fish, shrimp, crab, amphibians

• Build up of gases- adding to global warming

Effects of

Ozone

DepletionEfforts to Reduce Ozone Depletion

• Worldwide Ban by the Montreal Protocol

(1/1/00) on all CFCs use on new

refrigerators and freezers

• Use Less Harmful Propellants

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Fertilizer Runoff

Nitrogen/Phosphorus

Causes For Fertilizer Runoff

• Nitrogen & Phosphorus in fertilizers

contaminates lakes & ponds

- an increase in chemical nutrients that stimulate

excessive plant growthEffects

• Excess Algae growth, decreases O2 availability & when decomposes produces a lot of CO2

• Toxic to fish, insects, & aquatic life = death

• Food webs disrupted

Excess Algae Growth Efforts to Reduce Fertilizer Runoff

• Use less chemical fertilizers

• Use genetically altered plants

• Use good topsoil & composting

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Loss of Biodiversity

Key Facts

• Loss of different variety of organisms

from ecosystem

Loss of Biodiversity in

the Amazon RainforestCauses For A Loss of Biodiversity

• Deforestation

• Habitat Destruction

• Direct Harvesting

• Overhunting

• Overfishing

3 Sharks Die Every Second From Habitat

Destruction & Commercial Fishing Effects

• Disruption of food webs

• Extinctions

• Loss of potential medicines

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Medicines

Come From the

Living World

Efforts to Reduce the Loss of

Biodiversity

• Create State National Parks

• Pass & Enforce hunting & fishing laws

• Reforestation

What Do You Believe?

Position 1:

Enhanced Greenhouse Effect ?

- The extra quantities of greenhouse

gases into the atmosphere due to human

activities.

• Natural variability of the sun’s energy

output and its’ orbital changes.

Position2:

Climate is Affected ByThe Milankovitch Cycle

• Cycles in the Sun’s energy output vary

(brightness)

• Earth’s movement: orbital shape, tilt,

spin, & wobble

During the 100,000 yr cycle of orbital change,

glaciers dominate for 60-90,000 yrs in cold

phase & disappear in the warm phase.