Atmosphere
Essential Question: How are we changing
our atmosphere?
Learning Goals:
1. Be able to identify the
layers of the atmosphere.
1. Describe what molecules
make up the atmosphere.
Atmosphere
∗ Atmosphere: thin layer of gases surrounding earth
∗ Troposphere: layer of atmosphere closest to earth
(what we breath!)
∗ Is 78% nitrogen (N2), 21% oxygen (O2)
∗ 1%: H2O vapor, carbon dioxide (CO2), & argon
Create a Pie Chart and
Describe Each Item
A. Nitrogen - 78% - Dilutes oxygen and prevents rapid burning at the earth's
surface. Living things need it to make proteins.
B. Oxygen - 21% - Used by all living things. Essential for respiration. It is
necessary for combustion or burning.
C. Argon - 0.9% - Used in light bulbs.
D. Carbon Dioxide - 0.03% - Plants use it to make oxygen. Acts as a blanket
and prevents the escape of heat into outer space.
E. Water Vapor - 0.0 to 4.0% - Essential for life processes. Also prevents heat
loss from the earth.
F. Trace gases - gases found only in very small amounts. They include neon,
helium, krypton, and xenon
Bill Nye: Atmosphere
https://www.schooltube.com/video/d4985ed543054d03b968/Bill%20Nye%20Atmosphere
Atmosphere
∗ Air pollution: build up of harmful substances
in the air; 2 types:
1. Primary Pollutants - pollutants put directly into
air, already in harmful form
1. Secondary Pollutants - form when primary
pollutants react with each other or other
substances
∗ Ozone = car emissions + UV light + oxygen gas
∗ Smog = ozone + NO2 + other stuff
Atmosphere
Primary Pollutants :
1. Carbon Monoxide (CO) – colorless, odorless gas
∗ Sources: burning fossil fuels, vehicles, cigarettes
∗ Effects: Interferes with blood’s ability to carry oxygen
2. Nitrogen oxides (NOx) – red/brown, irritating gas
∗ Sources: burning fossil fuels in vehicles & factories
∗ Effects: lung damage & cancer; acid rain
3. Sulfur dioxide (SO2) – colorless, irritating gas
∗ Source: burning coal
∗ Effects: acid rain; lung damage
Atmosphere
Primary Pollutants continued:
4. Volatile Organic Compounds (VOC) = chemicals that form toxic
fumes
∗ Examples: formaldehyde, chloroform, methane
∗ Sources: burning of fuels, factories
∗ Effects: smog; cancer
5. Particulate matter = particles of liquid or solid in air
∗ Ex: dust, ash, smoke, pollen
∗ Sources: burning coal, vehicles, construction, agriculture
∗ Effects: lung problems, cancer
6. Lead = solid toxic metal
∗ Source: leaded gasoline (banned in 1986 in US), paint, batteries
∗ Effects: lead poisoning
Use your notes to fill out the chart in
your notes.
Atmosphere
Secondary Pollutants:
∗ Photochemical oxidants = products of atmospheric
reactions driven by sunlight
∗ Important example: Ozone (O3)
∗ Effects: harmful to plants & animals, makes smog!
Word Breakdown
Photo-: Light
Chemical: any substance
produced by or used in a
chemical process
Atmosphere
Other Forms of Air Pollution
1. Indoor Air Pollution:
•Mold & bacteria, Cleaning/ building materials,
Radon Gas, Asbestos, CO (carbon monoxide),
Cigarette smoke
• Sick building syndrome = headaches,
fatigue, nausea, respiratory problems, due
to work or home indoor air pollution
Atmosphere
Atmosphere
2. Light Pollution: leads to:
• Diminished view of sky
• Wasted energy
• Affects animals’ biological
cycles & migration
Atmosphere
3. Noise Pollution
• = unwanted pervasive noise
• Intensity of sound is measured in decibels (dB)
• For each 10-fold increase in dB, the sound intensity is 10X
higher (for example: 30 dB has 100x intensity of sound than
10 dB)
• Hearing Loss has doubled in US in last 30 years
• ~12% teens have permanent hearing loss
• 80 year old person in quiet Africa has better hearing than
30 year old American
Note Break
Which of these are
primary pollutants?
A. VOC
B. Smog
C. Particulates
D. Ozone
E. Carbon Monoxide
Which of the following are
considered types of air
pollution?
A. Indoor air pollution
B. Ocean acidification
C. Eutrophication
D. Sick-building syndrome
E. Noise Pollution
Atmosphere
• Air Pollution Effects:
• On Human Health:
•
•
•
•
Heart attack
Lung cancer
Asthma & Bronchitis
Immune problems
• The World Health
Organization
estimates that 5-6
million people die
prematurely every
year from illnesses
related to air
pollution
Atmosphere
• Air Pollution Effects:
• On Plants:
• Can cause discoloration &
death
• Can reduce crop yields
• Sensitive crops, such as soybeans, show
up to 50% reduction in yield after being
exposed to oxidants in the air
• Damage may cost up to $10 billion per
year in US
Atmosphere
Air Pollution Effects cont.:
Acid Precipitation
∗ = rain, snow, etc. with sulfuric
(H2SO4) & nitric (HNO3) acids
∗ Due to SO2 and NOx (primary
pollutants) reacting with H2O in
air (Secondary Pollutants)
∗ Normal rain is slightly acidic (pH
= 5.5) due to CO2 & H2O in air →
carbonic acid (H2CO3)
∗ Acid rain has pH < 5.0
pH is a measurement of how acidic or basic
a substance is, each whole number
represents a tenfold change in acidity. A pH
< 7 is acidic, 7 is neutral, > 7 to 14 is basic
(alkaline)
Atmosphere
Effects of Acid Rain
∗ Lowers pH of soil & water → harm
or kill plants
∗ Changes water’s pH → kills fish &
other organisms.
∗ Effects worse in spring: acidic snow
melts & rushes into lakes → rapid
change in pH, called acidic shock
∗ Can kill large numbers of fish & affect
the reproduction of fish and amphibians
∗ http://channel.nationalgeographic.com/
videos/acid-rain-invisible-menace/
Atmosphere
Effects of Acid Precipitation cont.
∗ Effects on humans:
∗ Puts toxic metals into soil →
crops, water, & fish
∗ Acids dissolve calcium carbonate
in building materials → damage
to buildings & monuments
∗ Concrete, marble, and limestone
Learning Goals
1. Identify environmental factors that
affect pollution
2. Steps humans have taken to regulate
pollution
What is the term that describes the following definition:
O3; a secondary pollutant of the troposphere?
Carbon monoxide
b. Sulfur dioxide
C. Ozone
d. Oxygen
2.What do we call a pollutant put directly into air
by human activity, already in harmful form?
Primary pollutant
b. Secondary pollutant
3. Light pollution can result in which of the following:
A. Inefficient energy use
b. Disrupting animal migration
c. Diminished view of night sky
d. All of the above result from light pollution
Atmosphere
Environmental factors that affect air pollution:
1. Topography
(mountains, valleys):
Shape of the land
2. Climate ( temp. &
precipitation)
• Seattle has great air
quality because high
rain
Atmosphere
What environmental factors affect air pollution?
3. Wind currents
• Pollution from Great Lakes & Ohio
found in Canada & Ireland
• Over years,
pollutants
biomagnify in arctic
food chain
• Grasshopper effect: when
volatile compounds evaporate • Whales, polar bears, sharks
have shown dangerously
from warm areas, travel by
high levels of pesticides,
wind, & condense over cooler
metals, etc.
areas
Atmosphere
What environmental factors affect air pollution?
4. Temperature Inversions =
when a layer of warm air
overlays cooler air
• Prevents wind currents from
dispersing air pollution
• Occur in valleys where air
movement is restricted; ex: Los
Angeles
1. Normal rain is slightly acidic due to carbon dioxide
and water reacting to form this acid:
Battery
b. Nitric
c. Carbonic
d. Sulfuric
2. The secondary pollutant nitric acid forms from
which primary pollutant’s reaction with water?
A. NOx
b. CO2
c. SO2
d. H2O
Atmosphere
How is air pollution regulated?
Clean Air Act (1970; 1990)
∗ Gave the Environmental Protection
Agency (EPA) authority to regulate
car emission & industry pollution
∗ Eliminated lead in gas, required
catalytic converters (cleans
exhaust)
∗ Requires industries to use
pollution-controlling devices ∗ Scrubber: machine that dissolves
many air pollutants in water
Note Break
True or False. Air pollution can reduce plant crop yields and result in loss of
money.
A. True
b. False
The majority of sulfur dioxide produced by industry comes from:
A. Oil refineries
b. Coal-burning power plants
c. Chemical plants
d. Dry cleaners
Acid precipitation has a pH lower than:
A. 1
b. 5
c. 7
d. 9
Acid rain reacts with the ______________ in building materials to cause damage:
A. Calcium carbonate
b. Limestone
c. Magnesium bicarbonate
d. Baking soda
Stratospheric Ozone Depletion
Ozone
Depletion
∗ Atmosphere: made up of layers:
∗
∗
∗
∗
∗
Troposphere
Stratosphere**
Mesosphere
Thermosphere
Exosphere
Ozone Depletion
Ozone layer
= layer in stratosphere
where ozone (O3) is
highly concentrated
∗ Serves to absorb most
of the UV radiation
coming from sun; i.e.,
protects us!
Ozone Depletion
Thinning of Ozone Layer aka Hole in Ozone
∗Caused by Chlorofluorocarbons (CFCs) & other chemicals that
destroy ozone – esp. over Antarctica
∗CFCs break down under UV radiation → form chlorine atoms, which
convert O3 into O2 + O
∗CFCs were invented by General Motors in 1930s & used in
fridges, air conditioners, insulation, aerosol, etc.
∗In 1974, Rowland & Molina showed that CFC’s destroy ozone
layer – took another 15 years for industries to comply
Ozone Depletion
Thinning of Ozone layer cont.
• Ozone loss = increased UV
radiation – leads to:
•Skin cancer
•Cataracts
•Reduced immunity
•Death of phytoplankton
(disrupts food chain)
Montreal Protocol: 1987
international meeting where
nations agreed to limit use of
CFCs.
Ozone Depletion
IMPORTANT NOTE:
•Ozone Depletion DOES NOT cause Global
Warming!
•Ozone depletion increases UV radiation – NOT heat!
≠
Global Climate Change
Global Climate Change
What controls our climate?
• Climate = long-term weather
conditions at a particular place
• Determined by:
1. Latitude – most important –
determines amount of
sunlight
2. Wind patterns
3. Oceanic current patterns
4. Geography
Global Climate Change
∗ Greenhouse Effect
= solar energy goes through the atmosphere & heats the
earth; as this heat radiates up from Earth’s surface, some
of it is absorbed by gases & warms the air
∗ Greenhouse gases (H20, CO2, N2O (nitrous oxide),CH4 (methane))
trap heat in the atmosphere
http://www.youtube.com/watch?v=OqVyRa1iuMc
∗ The greenhouse effect is a natural process, without which it is
estimated that Earth’s average temperature would be about
4°F (-16°C).
Global Climate Change
To Blame: Carbon Dioxide (CO2) increasing in atmosphere due to burning
of fossil fuels (oil, coal, natural gas)
Global Climate Change
Note on Carbon Dioxide (CO2)
∗ CO2 goes up & down in atmosphere each year:
∗ In spring/summer, northern hemisphere faces sun &
plants do photosynthesis = low atmospheric CO2
∗ In fall/winter, n. hemisphere faces away from sun &
plants not doing photosynthesis = high atmospheric
CO2
CO2 + H2O + sun = C6H12O6 + O2
Global Climate Change
Global Warming = increase in average temp. of
Earth; “caused” by too many greenhouse gases,
especially CO2
Global Climate Change = changes in precipitation,
wind, storm intensities, & average temps. over
time
Evidence:
∗ 11 of 12 years from 1995-2006 were the warmest years since record-keeping
began in 1850
∗ 100 year trend for 1906-2005 was a warming of 0.74˚C (1.3˚F) (the 1st half of
this period rose ~ .07 ˚C per decade and the 2nd half of this period rose ~ 0.13˚C
per decade).
∗ Changes in ocean temperature and sea levels (average sea level rise was
1.8mm/yr from 1961-1992 and ~3.1mm/yr from 1993-2003)
Global Climate Change
Consequences of Global Climate Change
∗ Rising sea levels as ice melts → flooding, beach
erosion
∗ Stronger storms
∗ Negative effects on agriculture & crop yields
∗ Loss of biodiversity due to weather changes, habitat
changes, pests & diseases, changes to food web
∗ Humans affected by change in food & water supply,
tropical diseases, extreme weather
Global Climate Change
Government Response to GCC:
∗ Kyoto Protocol = treaty written after 1997 international
conference where global warming was recognized by the
global community
∗ Treaty required developed countries to decrease CO2
emissions
∗ By 2008, 178 signed treaty, except US & Australia
∗ The use of alternative practices and regional initiatives,
such as using alternative forms of energy (wind, methane,
natural gas, and nuclear power) has helped reduce
emissions in various countries and localities
Air & Global Climate Change
What you can do for GCC:
1. Drive less: walk, bike, carpool
2. Get a hybrid or electric vehicle
3. Use less hot water: cooler showers, wash clothes
in cold water
4. Turn down your thermostat
5. Produce less waste & buy reusable products
(not plastics – made from oil)
6. Plant trees & support recycled paper