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AIR QUALITY AND
CLIMATE
ATMOSPHERE AND CLIMATE
• Weather - A description of short-term physical
conditions of the atmosphere.
• Climate - A description of the long-term weather
pattern in a particular area.
– Temperature
– Humidity
– Wind
– Rainfall
2
The Atmosphere
• Is a thin layer of gases that surrounds the earth
• Extends thousands of km above the surface
• The reason there is life on Earth – we are
protected from most of the sun’s radiation
• Allows some light to reach the surface, supplying
energy and allowing photosynthesis (O2 and CO2)
• 78% nitrogen, 21% oxygen, 1%= water vapor,
argon, carbon dioxide, neon, helium, and other
gases
HOW PHOTOSYNTHESIS CHANGED THE
ATMOSPHERE
• The early atmosphere contained little
oxygen.
• Bacteria appeared about 4 bya and evolved
the ability to perform photosynthesis
6CO2 + 6H2O + sun energy → C6H12O6 + 6O2
• When organisms break down food molecules
during cellular respiration, CO2 is released into
the air.
C6H12O6 + O2 → CO2 + H2O + Energy
The 5 Layers
EXOSPHERE
Troposphere
– 75–80% of the earth’s air mass
– Closest to the earth's surface
– 0-11 km above sea level
– Chemical composition of air
• Nitrogen 78%
• Oxygen 21%
• H20, CO2, trace amounts of others (Ar)
– Weather, climate and all life forms exist here
– As altitude increases, temperature decreases
Stratosphere
• 11-50 km (6-30 miles) above Earth's surface
– Similar composition to the troposphere, with 2
exceptions
• Much less water (1/1000)
• O3, ozone layer
• As altitude increases, temperature increases
• Air motion is horizontal
• Airplanes fly here
THE OZONE LAYER
• O3
• Located in the stratosphere
• Absorbs most of the UV light from the sun
– UV light can cause genetic damage to living
organisms- can cause skin cancer, faster aging, and
cataracts, can kill one-celled organisms
(phytoplankton) that live in the surface of the
ocean, and interfere with photosynthesis, resulting
in lower crop yields
• The ozone in the stratosphere acts as a
sunscreen for Earth and its inhabitants.
Mesosphere
 50-80 km (30-50 miles)
 Middle atmosphere – Air thin, pressure low,
 Need oxygen to live in this region. Air quite cold
-90°C (-130°F) near the top of mesosphere
Thermosphere




80-500 km (50-310 miles)
Very few atoms and molecules in this region.
Intense UV – breaks O2 and N2 bonds
International Space Station is here
Greenhouse Effect
• Greenhouse effect – the trapping of infrared
radiation from the sun by gases in earth’s
atmosphere which warms the planet
• Raises earth’s temp to an average of 59 ⁰F.
Without the
greenhouse effect,
the average temp
would be 0⁰F.
Global Warming
• Global warming – increase in Earth’s
average surface temp. caused by an
increase in greenhouse gases
EVIDENCE OF GLOBAL
WARMING
• Earth’s average temperature has risen 1 ° F in
last 100 years.
• Some argue natural fluctuation; however,
corresponds w/ rising greenhouse gases.
• According to the EPA, the global surface
temperature has increased 0.9°F since 1880.
– The Earth’s surface is currently warming at a rate
of about 0.29ºF/decade or 2.9°F/century
EVIDENCE OF GLOBAL
WARMING
– The eight warmest years on record (since 1880)
have all occurred since 2001, with the warmest
years being 2005 and 2010.
– Arctic temperatures have increased twice as fast
as the rest of the Earth.
Greenhouse Gases
Methane (CH4) – 21 times more warming effect than
CO2 and increasing at 8 times the rate.
• Methane production is faster than broken down
• Main sources are wetlands, rice fields, fossil fuels,
livestock, and landfills
• Remains in the air about 12 years
Greenhouse Gases
• Nitrous oxides – slow to breakdown (120 yrs)
– Sources are fossil fuels, fertilizers, deforestation
• CFCs– slow breakdown; absorb 10,000 X more
infrared than CO2 (100 + years)
– Sources are foams, aerosols, refrigerants, solvents
• Water vapor – Warmed by CO2,
the atmosphere is thus able to
absorb more water vapor. And
that water vapor, in turn, causes
further warming—it amplifies
the effects of carbon dioxide.
CFCs
• CFCs that are
released in the
troposphere can
take 10-20 years to
float into the
stratosphere.
• One single chlorine
atom can destroy
10,000 + ozone
molecules and
remain in the
stratosphere 65-385
years!
The Ozone Hole
• Depletion of the ozone layer allows more UV
light to reach the Earth’s surface
STOPPING THE OZONE EATERS
75-85% of the ozone loss was from CFCs
and other ozone depleting chemicals
• The Montreal Protocol – 1987
• The Copenhagen Protocol - 1992
– Nations agreed to reduce their production of CFCs
– US pledged to ban all substances that posed a danger
to the ozone layer by 2000
– Developed countries agreed to set up a fund to help
developing countries switch to CFC substitutes
• CFCs remain active for more than 30 years, so it
will take decades for the layer to recover.
THE NUMBER 1 SOURCE OF CFCs ARE LEAKING
AIR CONDITIONERS!
CFCs
• A greenhouse gas AND an ozone-depleting
chemical.
Melanoma cancer
Basal cell carcinoma
Over 1 million new diagnosis each year.
• About 90% of non-melanoma skin cancer is caused by ultra-violet
exposure.
• The UV rays of the sun are responsible for most non-melanoma skin
cancers. Unprotected exposure to these rays can come from being
outdoors, lying in tanning beds, and even having exposure through
your car or home windows.
• Skin cancer accounts for nearly 50% of all cancers.
• It is the most common type of cancer in men over 50.
Greenhouse Gases
CO2 – most abundant greenhouse gas (GHG)
Sources: burning fossil fuels, deforestation
Ice cores have shown that CO2 increasing in atmosphere –
35% higher than pre-Industrial Rev.
• Natural cycling of CO2 levels
• Seasonal shift in CO2 production; high fall; low spring
• 1 kg burned fossil fuels = 3 kg CO2
Sources of Greenhouse Gas Emissions
Largest Emitters of Carbon Dioxide
Bill Nye Climate Change 101
(4 min)
• http://www.smithsonianmag.com/videos/cate
gory/3play_1/climate-change-101-with-billnye-the-science/?no-ist=
CO2 - DiD you know…
• Burning 1 gallon of gasoline produces 9 kg of
carbon dioxide?
• Using one kWh of electricity from a coal-fired
generating plant produces 1 kg of carbon
dioxide?
• Burning 100 cubic feet of natural gas produces
5.5 kg of carbon dioxide?
• 1 kg= 2.2 pounds So 1 gallon produces almost 20
pounds of CO2
Measuring
Carbon
Dioxide
in
the
Measuring Carbon Dioxide in the Atmosphere
Atmosphere
There is a carbon dioxide
detector in Mauna Loa in Hawaii.
This allows measurements far away from cities and
forests.
The winds over Mauna Loa have come thousands of
miles across the Pacific Ocean, swirling and mixing as
they traveled.
Measuring Carbon Dioxide in the
Atmosphere
• Charles Keeling’s took the first measurement,
in March of 1958, it was 0.0314 percent.
– Slightly higher in the winter.
– Slightly lower in the summer.
– Why? Photosynthesis
• These levels have rose steadily over the last 50
years.
http://www.weather.com/video/a-first-in-800000-years-for-atmosphere46863?collid=/news/top-stories
Video (1 min)
ICE CORE SAMPLING
•
Russian Vostok Station EPICA- European Project
in East Antartica
for Ice Coring in
In January 1998, the collaborative iceAntarctica
drilling project between Russia, the
United States, and France at the
Russian Vostok station in East
Antarctica yielded the deepest ice core
ever recovered, reaching a depth of
3,623 m (11,886 feet- a little more
than 2 miles deep)
• Preliminary data indicate the Vostok
ice-core record extends through four
climate cycles, with ice slightly older
than 400,000 years before present.
• In 2004 EPICA drilled
deeper than Vostok did and
were able to measure the
carbon dioxide levels over
the past 650,000 years.
Older Climate Data?
• The data presented only goes back about
650,000 years.
– Limited by the age and extent of the Antarctic
glaciers.
• Deep sea cores have also been measured:
30
Average surface temperature (°C)
Average Global Temperature over the
Past 900,000 Years
17
16
15
14
13
12
11
10
9
800
700
600
500
400
300
Thousands of years ago
200
100
Pres
900
Fig. 16-2a, p. 369
Temperature Changes Over Past
22,000 Years
Temperature change (°C)
2
Agricultural Revolution
1
Medieval warming period
0
–1
–2
–3
End of
last ice
age
Little ice age
–4
–5
20,000
10,000
2,000
1,000
Years ago
200
100
Now
Fig. 16-2b, p. 369
Temperature Changes Over Past 1,000
Years
Temperature change (°C)
1.0
0.5
0.0
–0.5
–1.0
1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2101
Year
Fig. 16-2c, p. 369
CO2 in the ice core record video
(3min)
• https://www.youtube.com/watch?v=oHzADlXID8
Medieval Warming Period
• Occurred sometime between 800-1300 A.D.
• This produced milder winters and longer summers
throughout Europe.
– Western Europe thrived with abundant crops and
overall healthy populations.
– Viking explorers were able to colonize Greenland
and Labrador.
• Much of North America, South America, and Asia
experienced severe droughts.
– May have been a major cause of the downfall of
the Mayan empire.
35
• Causes are unknown.
Little
Ice
Age
Period of cooling lasted from the about 1300-1800 A.D.
•
• Effects of this cooling period:
– Colder winters in North America and Europe.
– Severe food shortages and famines were
commonplace.
• The Viking colony in Greenland died out.
• Causes of this “little ice age”?
– Decreased solar activity
– Increased volcanic activity
– Ocean conveyor was disrupted – possibly by melting
glaciers.
36
Average surface temperature (°C)
Average Global Temperature Over Past
130 Years
15.0
14.8
14.6
14.4
14.2
14.0
13.8
13.6
1860
1880
1900
1920
1940
1960
1980
2000
2020
Year
Fig. 16-2d, p. 369
Hurricane Katrina
• Formed over the Atlantic in
August of 2005.
– Crossed Southern Florida
as a category 1 hurricane.
– Strengthened very quickly
over warm waters of the
Gulf of Mexico
• Made landfall over Louisiana
as a Category 3 hurricane.
38
New Orleans
• Parts of New Orleans are below sea level.
• The levees holding back the Mississippi river and the
shoreline were not maintained properly.
•Immediate
connections
were made
between global
warming, the
unusually warm
Gulf of Mexico,
and the
hurricane.
39
Global Warming and Hurricanes?
• No evidence to link climate change and frequency
of hurricanes and typhoons.
• Studies do show evidence between ocean surface
temperatures and hurricane intensity and duration.
– Duration and strength of hurricanes has increased about
50% over the last 30 years.
– Previous models showed a 5% increase for every 1°C.
40
El Niño/ La Niña Weather Patterns
• El Niño and La Niña – are oscillations in the
Pacific’s ocean-atmosphere system that
dramatically affect weather patterns. (usually
occur every 3 to 5 years)
• A sudden change in El Niño behavior occurred
between 1976-77.
• There have been more frequent El Niño years
than in prior history.
• Relation to global warming is unknown.
41
Global Warming Effects on Poles
• 99% of sheet ice is located in Antarctica and
Greenland
• Ice is melting worldwide, but especially quickly at
the poles.
– As a result…
• Ocean levels have risen about 3.0mm per year in the 10
years.
• Adelle penguin population is down to 1/3 its normal level.
• Multiple populations of polar bears are declining.
42
Flawed Predictions
•
The 2007 Intergovernmental Panel on Climate Change
(IPCC) report predicted a complete loss of the Himalayan
glaciers by 2035.
• This was later retracted, as it was based on a single
interview of a scientist who denied making the
prediction.
• This rate of melting
would require global
warming to be occurring
at 2-3x the rate it is
currently.
• This error damaged the
43
credibility of the report.
Scientific Consensus?
•
•
Survey was taken in 2004 of 928 abstracts of
peer-reviewed papers relating to climate change.
• None disagreed with the IPCC conclusion.
Survey taken in 2009 of 3,146 Earth Scientists
(defined as publishing more than half of their
peer-reviewed papers on climate change)
•
44
97% agree with the IPCC conclusion.
Predicted Results Of Global
Warming
• Weather patterns will change - more
hurricanes, typhoons, flooding and droughts
• Agriculture – weather patterns will move
farther north, shifting farmland
• Sea Levels - polar regions warm, icebergs
melt, sea levels rise. Warming water also
expands.
• Coastal areas may flood
Melting of Alaska’s Muir Glacier
between 1948 and 2004
Predicted Results Of Global
Warming
• Human health will be affected
– Heat index, more ground level ozone, more
infectious diseases.
– Diseases that normally occur near the equator will
move northward. Diseases spread by mosquitoes
and other insects due to warmer/wetter climates.
– Malaria, dengue fever, yellow fever and
encephalitis
Predicted Results Of Global
Warming
• Plant and animal species may migrate to maintain their
preferred habitats
• Not all plants can adapt- some cannot disperse their
seeds adequately
• Certain birds/fishes may migrate
• Not all can adapt- ponds will dry up,
land-locked fish cannot seek colder
rivers
• Those that cannot adapt/migrate
may experience regional extinction
Blue winged teal
Evidence of Climate Change with
Walruses
• http://news.discovery.com/earth/videos/glob
al-warming-videos.htm
Global Cooling
• Global cooling: natural
• Planetary albedo – low, thick clouds reflect
sunlight, prevent warming
• Volcanoes – dust reflect radiation
• Sulfate aerosols – from pollutants, create
haze, reflecting sunlight
Kyoto Protocol
• The Kyoto Protocol is the first international
agreement (UN) to fight global warming.
• It set targets for nations to reduce greenhouse gas
(GHG) emissions .
– 5% decrease against 1990 levels over the fiveyear period 2008-2012.
• It was signed by 141 nations, including all European
and all other developed industrial nations except
the U.S. and Australia.
– Went into effect on February 16, 2005, and
expires in 2012.
• Pres. Clinton supported
• Pres. Bush did not sign
Cap and Trade System
–A limit on the amount of carbon dioxide any
specific factory or power plant can produce.
–Permits (or credits) are required depending
on how much carbon dioxide is emitted.
• An organization can purchase additional
credits from other organizations that do
not need them.
CARBON SINK
• A carbon sink is anything that absorbs more
carbon that it releases, while a carbon
source is anything that releases more carbon
than is absorb.
• Forests, soils, oceans and the atmosphere all
store carbon and this carbon moves between
them in a continuous cycle. This constant
movement of carbon means that forests act
as sources or sinks at different times.
Solutions to Global Warming
Solutions
Global Warming
Prevention
Cut fossil fuel use (especially coal)
Cleanup
Remove CO2 from smokestack
and vehicle emissions
Shift from coal to natural gas
Improve energy efficiency
Store (sequester) CO2 by
planting trees
Shift to renewable energy resources
Sequester CO2 deep underground
Transfer energy efficiency and
renewable energy technologies to
developing countries
Sequester CO2 in soil by using no-till
cultivation and taking crop land out
of production
Reduce deforestation
Use more sustainable agriculture
Limit urban sprawl
Reduce poverty
Slow population growth
Sequester CO2 in the deep ocean
Repair leaky natural gas pipelines
and facilities
Use feeds that reduce
CH4 emissions by
belching cows
Fig. 16-13, p. 379
Other Ideas?
• The StratoShield is an idea developed to combat global
warming by blocking some of the sunlight entering the
Earth’s atmosphere.
• Inject sulfur dioxide or particulate pollutants into the
stratosphere.
– This would be too high in the atmosphere to be
directly breathed or cause acid rain.
– Blocks out just enough sunlight to bring global
temperatures down to acceptable ranges.
https://www.youtube.com/watch?v=JrimZzgqwdo
Video of how a StratoShield works
Other Ideas? Geoengineering
• http://news.discovery.com/earth/videos/glob
al-warming-videos.htm
Fifteen Ways to Cut CO2 Emissions
We Can Prepare for the Harmful Effects
of Climate Change
•
•
•
•
•
•
•
•
Reduce greenhouse gas emissions as much as possible
Move people from low-lying coastal areas
Limit coastal building
Remove hazardous material storage tanks away from the
coast
Genetically engineer crops more tolerant to drought
Stockpile 1–5 years of key foods
Waste less water
Connect wildlife reserves with corridors
What the Dominican Republic is
doing to fight climate change.
• http://www.sciencedaily.com/videos/542529.
htm
Haiti
Dominican
Republic
The Most Terrifying Video You Will
Ever See
(9 min)
• http://www.youtube.com/watch?v=zORv8wwi
adQ
• (Fill in the chart in your notes)
Is Global Warming Real?
(8 min)
• https://www.youtube.com/watch?v=r78bZfy8oU
Bill Nye discusses Global Warming
• https://www.youtube.com/watch?v=sm05Mc
ah0i8
• https://www.youtube.com/watch?v=tuuZBaM
u_4I
(4min)
(6min)
REVIEW
1. Name the 5 greenhouse gases.
2. What is the main greenhouse gas?
3. Why is the greenhouse effect good for our planet? Why
is it harmful?
4. Name 3 sources of both CO2 and CH4.
5. Name 2 sinks for CO2.
6. List 5 effects of global warming.
7. List 5 things you can do to reduce global warming.
8. How can we prepare for global warming?
9. Name the treaty that dealt with reducing greenhouse
gas emissions.
10. Name 3 sources of global cooling.
REVIEW
1. In what layer of the earth’s atmosphere is the
ozone layer?
2. Why is the ozone layer beneficial?
3. What is the main chemical that affects the
ozone layer?
4. Why was this chemical used in so many
products?
5. Name the treaty that was signed to decrease
ozone depleting chemicals.
6. What is the main source of CFC emissions?
• The average amount of CO2 per capita
produced in America is 19.8 tons, which is
39, 600 pounds!