Transcript Ch 9 AIR POLLUTION

Chapter 9
Chapter 9 Objectives
9.1 What is Air pollution?
 9.2 Types of air pollution: heat, light, noise,
smog

9.3 ISSUES: acid rain, Ozone layer, global
warming and climate change
 9.4 Ways to reduce air pollution

Lesson 1 Objectives
Define air pollution
 Give examples of natural and human
sources of air pollution
 Describe how air pollutants get into
and out of the atmosphere

As of 2012, 7 of the 10 most air-polluted
cities are in China!
Smog – these are NOT clouds
smoke + fog = smog
What is in the air?
Mostly nitrogen (78%)
 oxygen (21%)
 Small amounts of

Carbon dioxide
 Water
 Argon


And some solids too
Dirt
 Pollen

What is in the air?

Particulate matter
Bits of solids and liquids in the air
Can fall bc of gravity or precipitation
 If smaller, can go FURTHER

Air Pollutants

Materials in the air that can harm
living and nonliving things
Air Pollutants
Can be natural
 Volcanoes
 Forest fires
 Ash
 Pollen
 Dirt
 Usually not concentrated enough to harm
living things

Air Pollutants

Most damaging pollution comes from
human activities
Paint fumes
 Pesticide sprays
 Smoke from wood-burning stoves
 Cement dust
 Mining dust

Air Pollutants
Most comes from ONE source
 BURNING FOSSIL FUELS creates 90%
of air pollution in the US
 Factories
 Power plants
 Transportation

2 Categories of Air Pollutants:

Primary air pollutants
Released directly by human or
natural sources
 Ex. CO from mufflers


Secondary air pollutants
Formed from chemical reactions
between substances in the air
 Ex smog

Outdoor Air Pollution
Indoor Air Pollution
 Can often be worse than
Measured
outdoor pollution
outdoors
 Carpet chemicals,
 What we usually
cleaning sprays, tobacco
think about when
smoke
we say air
 People spend at least
pollution
90% of their time

indoors so it can be a
serious health issue
Outdoor vs. Indoor Air Pollution
How Air Pollution Affects
HUMAN HEALTH:
Eye and throat
 Heart
 Lung
 Respiratory (breathing)
 Asthma and emphysema


~600,000 people a year die earlier than normal
due to air pollution
How Air Pollution Affects
ENVIRONMENT
Air pollutants can sink into water
and affect aquatic wildlife
 Can affect plant growth
 Can damage statues and buildings

Solutions

Must reduce emissions (release) of
pollutants from source like factories and
vehicles
Air is hard to clean up!
 air moves so communities affected may be
far from those that created it

Impacts and Solutions

Clean Air Act
 Law that sets national standards for air
quality
Changed as needed when new pollutants
are discovered
 As of 2004 it is 465 pages long!

Impacts and Solutions

Have already made improvements:
Gasoline used to have lead in it
 Burning it released lead into the air
 Can poison people and cause developmental
problems in children
 Now gasoline is unleaded


Level of lead in people’s blood dropped by 50% by
1980
Lesson 2




Describe what smog is and where it occurs
Explain what an urban heat island is
Explain how noise can be a type of pollution
Give examples of how light can pollute

In 1970
Serious air pollution
 So dark during the day that people used
headlights
 Air could destroy a woman’s stockings as she
walked down the street

SMOG TYPES:

Industrial



Dark grey

Caused by: burning coal
and oil

Consists of:
SOx + PM
 (London 1952 -12,000
people died from smog

Photochemical

Brownish
Caused by: motor vehicles
(NOx + sunlight)
Consists of:

NOx, O3, + PAN

Where is ozone suppose to be??

Which SMOG is it found in?

Why is breathing ozone bad?



Breathing difficulties
Headaches
Fatigue (weakness)

Makes eyes water and sting!

Cars made w/ catalytic converters now



Reduce emissions from cars’ exhaust systems
Reduced emissions per car BUT…..
today there are more cars so photochemical
smog is still a problem 

Urban Heat Island Effect


Cities are usually few degrees hotter than
surrounding areas
Why?
Waste heat from urban activities (subway,
building vents, lights, cars …)
 Loss of natural vegetation in cities
 Asphalt, brick, metal are dark in color and
absorb heat




CAUSES: more heat bc pollution traps
Also increases energy used for cooling
Solution:
Plant more trees
 Use lighter colors


Defined as noise that interrupts daily life

Comes from
transportation
 Construction and industry



Tends to be concentrated in urban areas
Causes stress, disrupts wildlife, damages
hearing

Major urban areas glow with light

Caused by:
More lights than needed for safety
 brighter than necessary
 Light is allowed to spread up and out

people stay awake
 harder to drive at night
 Disrupts the movement of wildlife

Light pollution could be contributing to cancer, depression, and obesity
our bodies need darkness to produce the hormone melatonin, and
melatonin protects our DNA, ultimately preventing cancer.
9.3-9.4

1960’s
 Freshwater lakes and forests
biodiversity declining
 water and soil were acidic
 Discovered that the acid was coming
from the air
Atmosphere
ACID RAIN
 How do you make it?


Water vapor + pollutants  drops pH
What are the 2 main acid rain pollutants?
 SOx and NOx
 (Sulfer and Nitrogen Oxides)

Dry deposition
 When acids settle as DUST or GAS
(on trees, buildings, water, and land)
 Wet deposition
 When acids come as PRECIPITATION
(Includes rain, snow, sleet, fog, and
dew)

Background info…
What are forms of precipitation?
 Rain, snow, sleet, hail

What does pH measure?
 Amt of HYDROGEN

What are the numbers on the scale go
from?
 0 – acidic, 7- neutral, 14- basic

What does the pH scale measure?

#’S
WORDS
EX.
IONS
AMT
OF H
tastes
H3O+
HYDROGEN
What damage can acid rain do?
1.
Changes pH of water (lakes,
rivers)
2. Kills sensitive plants
3. Damages man-made
structures

Ecosystems with high acidity lose
biodiversity
Snails, crayfish, salmon, and trout die
 But water beetles, bloodworms and
eels like it!




Acid rain is a major problem in Europe,
Scandinavia, China, southeastern Canada,
and northeastern US
Tall smokestacks blow pollutants to other
places
More than ½ of Canada’s acid rain comes
from the U.S.

Acid rain effects are visible all over the
world
 Maple trees are dying in Vermont
 4,000 lakes in Sweden contain no fish
 ¼ of the lakes in New York’s
Adirondack Mountains are
biologically DEAD!

Clean Air Act requires power plants to
reduce emissions of sulfur dioxide and
nitrogen oxide
SOx –scrubbers on smokestacks
remove sulfur
 NOx – try to use less cars

Scrubbers in smokestacks
WET
DRY
Covanta Energy to install a state-of-the-art particulate
emissions control system, called a baghouse, at the Essex
County Resource Recovery Facility located in Newark.
OHHYDROXYL
- a type of RADICAL (2 or more atoms
that act like 1 atom; wants to REACT!)
Vocab u should know:
Acid
 Acid rain
 Acid deposition
 Dry deposition
 Wet deposition
 Base

pH
Neutral
Scrubber
Smokestack
Radical
Another term for acid rain is ?
A ____ substance is neither an acid nor
base
Devices that clean sulfur from smokestacks
are called ?
Substances with a pH higher than a 7 are ?
An ecosystem with high acidity loses ?
Is ACID RAIN primary or secondary
pollutants?
Which type of smog can you associate
ACID RAIN with?
Atmosphere
OZONE LAYER
 Ozone is O3 so how do you make it?


Oxygen (O2) + Monoxide (O)  Ozone (O3)
What light wavelengths does it protect
us from?
 UV (ultraviolet radiation)

What is the “Hole in the Ozone Layer” ?
 Where layer of ozone doesn’t exist

With a huge hole, what can UV do to us?
1. Skin cancer! (Melanoma)
2. Eye damage (Glaucoma)

How do you breakup Ozone (O3)?
 Release pollutants! -CFC’s and aerosol

Where is the thinnest part of the ozone? “The
Hole”?
CFC’s = ChloroFluoroCarbons
 Break apart O3 into O2 and O

Where do CFC’s come from?
 aerosol cans, cooling chemicals (fridges),
cleaning stuff


Aerosol comes from hairsprays..etc
Use non-aerosol !
Solution:



STOP emitting CFC’s and aerosol
into the air!
And we have!  The ozone hole is closing
up.
Your grandkids will be safe to play and tan
outside.
#3
Climate Change

Montana’s Glacier National Park
 Glaciers are melting and shrinking
 By 2030, there may be NO glaciers
left
Chaney Glacier Terminus, Montana
Global Warming
GREENHOUSE EFFECT
 How does a greenhouse work?
Sun and warmth goes in, then traps
warmth inside

What are the pollutants that traps
heat from the sun?
 CO2 and CH4 (methane)

Where does CO2 come from?
1. Burning fossil fuels
2. less forests
What are fossil fuels??
Oil, gas, coal … our ENERGY
What does less forest have to do with more
CO2 in the air?
Plants can’t take in CO2 in photosynthesis!


Where does methane come from?
FARTS!
1. Burn fossil fuels
2. Raise livestock (thats a lot of pooping!)
2. Landfill breakdown
3. Grow rice
4. Natural sources (wetlands, termites,
wildfires)
What organisms do you think break down
poop and garbage to release methane?

bacteria
What is the scientific name for it?
 Prokaryote

What does it NOT have?
 Nucleus and organelles

GLOBAL WARMING
What are the effects of warming the Earth?
Ice caps melt
Oceans rise
Weather gets funky
Animals/plants die if sensitive to temperature
Why does the weather get funky if it gets warm all
over?
Temp. of oceans controls winds/evaporation/rain
amounts/..etc
Global Warming vs. Climate Change


“Global Warming” is when you mean WE
cause the warming of the earth bc of CO2
and methane
“Climate Change” is when you mean the
“natural” warming up of the earth




Since June 2010, public understanding that
global warming is happening rose to 64
percent
belief that it is caused mostly by human
activities declined to 47 percent
The number of Americans who worry about
global warming held stable at 52 percent
the number of Americans who said that the
issue is personally important to them
dropped to 60 percent
What do MOST scientists believe?
current changes are due
to human activities

A Changing Climate


Average global temperature has risen
o
between 0.4 – 0.8 C since the 1800’s
The first five years of the 2000’s had four
of the five hottest years on record
CO2 vs Temp




88% of Democrats, 59% of Independents and
61% of liberal/moderate Republicans think
global warming is happening, compared to only
28% of conservative Republicans;
82% of Democrats and
65% of liberal/moderate Republicans support
strict carbon dioxide emission limits on existing
coal-fired power plants to reduce global warming
and improve public health, compared to only
31% of conservative Republicans.
Why would we want some gases in
atmosphere to trap the sun’s heat?

Bc it does keep us warm
for life (and not a frozen
planet)
The Greenhouse Effect

The U.S. emits 1/5 of all
greenhouse gases emitted
worldwide
Btw…

How can we predict what will happen?
 Computer Models
 Calculate air and sea temperatures
 Calculate changes in sea level and
glaciers

Impacts of Climate Change
Poor polar bears!
 Arctic ice forms later
and melts earlier
 Bears need this ice to
hunt seals
 They are becoming too
thin to reproduce
 Some are even starving
and drowning
Solutions

1. Clean Air Act 1970
2. Reduce fossil fuel use and use alternative
forms of energy
“Go Green” (use less coal, oil, gas) (DO NOT
talk about using less water or ozone
depletion)
 How would us recycling, help out global
warming?
 Less material to be made  less crap
released into air from factories
3. Carbon Sequestration
-keeping C stored in SINKS
Forests, oceans,… are all carbon
sinks – places that absorb and
store carbon dioxide
Addressing Climate Change