Transcript Air Pollution - Bethpage Union Free School District

What is wrong with this picture?
Air Pollution
Aim: What are the major causes
of air pollution?
1. Air pollution: any substance in
the atm that is harmful
-can occur naturally or by human
activities
2. Natural sources of pollution:
a. Volcanoes can put
particles into the air
(dust, ash, smoke)
b. Forest Fires
c. salt from oceans
d. dust storms and soil
erosion
e. pollen and molds
3. Human Activity:
•
Most air pollution is
the result of
burning fossil fuels
Examples:
- Gasoline in cars
- Power plants
- Factories
•
Over farming soil
erosion
4. What are fossil fuels?
• fuel made from the
remains of living
organisms
compressed over
millions of years.
Examples:
-Oil
-Natural Gas
-Coal
-petroleum
5. Aerosols in the air
• Particles from
volcanoes, forest
fires, and soot block
sunlight affects
temperature on Earth
• contributes to formation
of clouds also affects
temp
Soot
• Black particles that
are made from
burning fossil fuels
6. Photochemical Smog
a. Sunlight reacts with
chemicals from burning
fossil fuels to make
smog.
b. A dangerous ingredient
in smog is ground
level ozone.
c. Smog irritates breathing,
damages plants & algae,
destroys plastics &
rubber
Is Ozone good or bad?
• Why is it good in the stratosphere?
• Why is it bad close to the ground?
7. Stratospheric vs.
ground ozone
a. Stratospheric ozone absorbs
the damaging UV rays of the
sun ;-)
b. Ground ozone is a part of
smog and contributes to air
pollution ;-(
* Ozone: Good up high, bad nearby
Air Quality Index
• AIRNow – Home
• http://www.Hazecam.net
What is the #1 cause of smog?
What’s eating the ozone?
http://www.youtube.co
m/watch?v=qUfVMogIdr8
&feature=related
8. Ozone hole
a. Over Antarctica
b. Chlorofluorocarbons (CFCs)
used in refrigerators, air
conditioners and aerosol cans
break up the O3 molecules
c. CFCs were banned in 1998
d. Ozone layer will naturally be
repaired
Why over Antarctica?
Cold temperatures speed up the destruction
of ozone
The ozone
“hole” is
more like a
bald spot…
it’s thinning
but not
completely
gone.
9. Acid
Precipitation
a. precipitation is
naturally acidic
Acid Rain
What is the pH of “normal” rain?
• pH of 5.6 because of
dissolved CO2 in it
What is an acid?
b. Burning of fossil fuels releases sulfur dioxide
(SOx) and nitrogen dioxide (NOx).
c. Moisture in the air reacts with these chemicals
to produce sulfuric and nitric acid.
d. causes Chemical
weathering
e. affects ecosystems
f. turns plants brown
-pine needles fall off
10. Global Warming
• burning fossil fuels releases CO2 into atm
• it acts as a blanket and traps heat in our
atmosphere (greenhouse effect)
Summary: Explain why some
states may display this message to
commuters.
Acid Rain Review
• acids and bases
• Air pollution