Global Warming
Will Human-Induced Climate
Change Destroy the World?
By Rich Deem
www.GodAndScience.org
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Introduction
• Is the world getting warmer?
• If so, are the actions of mankind to
blame for earth’s temperature
increases?
• What can/should be done about these
issues?
• Are the potential resolutions worth the
cost to implement them?
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
• Originally very hot
• Sun’s energy output only 70% of
present
• Liquid water present ~4.3 billion years
ago (zircon dating)
• Much of earth’s early history erased
during late heavy bombardment (~3.9
billion years ago)
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
• Photosynthesis began 3.5-2.5 billion
years ago
 Produced oxygen and removed carbon
dioxide and methane (greenhouse gases)
 Earth went through periods of cooling
(“Snowball Earth”) and warming
• Earth began cycles of glacial and
interglacial periods ~3 million years
ago
Earth’s Temperature
Solar
Sun
Energy
Solar
Energy
Earth’s Temperature
Sun
Solar
Energy
Radiative
Cooling
Earth’s Temperature
Sun
Solar
Energy
Radiative
Cooling
Earth’s Temperature
Sun
Solar
Energy
Radiative
Cooling
Sun
Greenhouse Effect
Earth’s Atmospheric Gases
Nitrogen (N2)
Oxygen (O2)
NonGreenhouse
99%
Gases
Water (H2O)
Carbon Dioxide (CO2)
Methane (CH4)
Greenhouse
1%
Gases
Sun
Runaway Greenhouse Effect
• 97% carbon dioxide
• 3% nitrogen
• Water & sulfuric
acid clouds
• Temperature:
860°F
Venus
Carbon Dioxide
CO2 (ppm)
420
Carbon Dioxide Levels
CO2 (ppm)
370
320
Muana Loa Readings
CO2 Levels Since 1958
370
350
330
310
40 30 20 10 0
270
220
Dome Concordia
170 600000
Vostok Ice Core
400000
200000
Time (YBP)
0
Carbon (109 metric tons)
Worldwide Carbon Emissions
8
7
6
5
Total
Liquid fuel
Solid fuel
Gas fuel
4
3
2
1
0
1750
1800
1850
1900
Year
1950
2000
Carbon (109 metric tons)
8
Annual Carbon Emissions
6
Annual carbon emissions
Atmospheric CO2
Atmospheric CO2 average
4
2
0
1955
1965
1975
1985
Year
1995
2005
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
China and developing countries
• Likely to double within 150 years:
 Increased coal usage
 Increased natural gas usage
 Decreased petroleum usage (increased
cost and decreasing supply)
Kyoto Protocol
• Adopted in 1997
• Cut CO2 emissions by 5% from 1990
levels for 2008-2012
• Symbolic only, since cuts will not
significantly impact global warming
Past Temperatures
D Mean Temperature (°C)
0.8
Recorded Worldwide
Temperatures
0.6
0.4
Decreasing
Flat
0.2
0.0
-0.2
-0.4
-0.6
1880
1900
1920
1940
Year
1960
1980
2000
Historic Los Angeles
Temperatures
Temperature (°C)
Annual Temperatures
Summer Temperatures
Winter Temperatures
22
25
17
21
24
16
20
23
15
19
22
14
18
21
13
17
20
12
16
19
11
15
18
10
1880 1900 1920 1940 1960 1980 2000
1880 1900 1920 1940 1960 1980 2000
1880 1900 1920 1940 1960 1980 2000
Year
Year
Year
2007 Temperature Changes
Compared to 1951-1980
-3
-2.5 -1.5
-1
-.5
-.1
.1
.5
1
1.5
2.5
3.4
Past Temperatures Measurement
• Proxy – a method that approximates a
particular measurement (e.g.,
temperature)





Ice cores
Pollen records
Plant macrofossils
Sr/Ca isotope data
Oxygen isotopes from speleothem calcite
(stalactites and stalagmites)
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
warmer than today
• Cool/warm cycles occur ~1,500 years
• Affect mostly Northeastern U.S. and North
Atlantic
• Mostly due to changes in thermohaline
circulation 
• Dramatic shutdown of thermohaline
circulation occurred 8,200 years ago as a
large lake in Canada flooded the North
Atlantic
Main Ocean Currents
Adapted from IPCC SYR Figure 4-2
Temperature History of the Earth
• For the past 3 million years, the earth
has been experiencing ~100,000 year
long cycles of glaciation followed by
~10,000 year long interglacial periods
• These climate periods are largely the
result of cycles in the earth’s orbit –
precession, obliquity, and eccentricity
Orbital Parameters: Precession
Apehelion
Perihelion
Orbital Parameters: Obliquity
24.5°
22.5°
Orbital Parameters: Eccentricity
Maximum: 0.061
Minimum: 0.005
Apehelion
Apehelion
Perihelion
NotScale!
To
to scale!
Orbital Parameters & Earth’s Climate
Precession
(22 ky)
Obliquity
(41 ky)
Eccentricity
(100 ky)
Temperature
1000 900 800 700 600 500 400 300 200 100 0
Age (kya)
Temperature History of the Earth
• For the past 3 million years, the earth
has been experiencing ~100,000 year
long cycles of glaciation followed by
~10,000 year long interglacial periods
• Last ice age began to thaw 15,000 years
ago, but was interrupted by the
“Younger Dryas” event 12,900 years
ago
Temperature (°C)
-25
-30
0.35
Younger
Dryas
0.30
Medieval Warm
-35
-40 Ice Age
0.25
Little Ice Age 0.20
-45
0.15
-50
0.10
-55
20
15
10
Age (kya)
5
0.05
0
Snow Accumulation (m/yr)
Younger Dryas Event
-8.0
Younger
Dryas
-7.5
d18O (China)
-7.0
-6.5
-6.0
-5.5
-5.0
-4.5
-4.0
16
15
14
13 12 11
Age (kya)
-34
-35
-36
-37
-38
-39
-40
-41
-42
-43
-44
10
d18O (Greenland)
Younger Dryas Event
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
 20°C higher at high latitudes
 1°C higher at the Equator
• Sea levels were 100 ft higher
• Causes
 CO2 levels that were 100 ppm higher
 Increased thermohaline circulation
Temperature History of the Earth
Eocene (41 million years ago)
• Opening of the Drake Passage
(between South America and
Antarctica).
• Increased ocean current exchange
 Strong global cooling
 First permanent glaciation of Antarctica
~34 million years ago
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
• Sea surface temperatures rose 5-8°C
• Causes
 Increased volcanism
 Rapid release of methane from the oceans
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
• Breadfruit trees grew in Greenland
• Causes
 Different ocean currents (continental
arrangement)
 higher CO2 levels (at least 2 to 4 times
higher than today, up to 1200 ppm)
Recent Temperature
Changes
Temperature Change (°C)
“Hockey Stick” Controversey
0.6
0.4
Direct temperature measurements
Mann et al. 1999
0.2
0
-0.2
-0.4
-0.6
-0.8
1000
1200
1400
1600
Year
1800
2000
Temperature Change (°C)
Is the Hockey Stick Correct?
2
Mann et al. 1999
Esper et al. 2002
1
0
-1
-2
800
1000
1200
1400
Year
1600
1800
2000
Is the Hockey Stick Correct?
Temperature Change (°C)
0.4
0.2
0.0
-0.2
-0.4
-0.6
Mann et al. 1999
Esper et al. 2002
Moberg et al. 2005
Mann et al. 2008
-0.8
-1.0
-1.2
0
400
800
1200
Year
1600
2000
Temperature Change (°C)
U.S. National Academy of
Sciences: June 2006
0.6
0.4
“2:1 chance of being right”
“high level of confidence”
0.2
0
-0.2
-0.4
-0.6
-0.8
1000
1200
1400
1600
Year
1800
2000
Atmospheric Temperatures
Temperature Cgange (°C)
0.8
Troposphere
0.6
1.5
Stratosphere
1.0
0.4
0.2
0.5
0.0
0.0
-0.2
-0.5
-0.4
-0.6
1980
1990
Year
2000
-1.0
1980
1990
Year
2000
CO2 (ppm) Antarctica
370
320
270
220
170
600000
400000 200000
Time (YBP)
31
30
29
28
27
26
025
SST (°C) Tropical Pacific
CO2 Concentration Vs. Temperature
Consequences of
Global Warming
Global Warming Primarily Impacts
the Northern Hemisphere
Temperature Change (°C)
Northern vs. Southern Latitude
Land vs. Ocean
1.0
0.8
0.6
Northern Hemisphere
Southern Hemisphere
Land
Ocean
0.4
0.2
0.0
-0.2
-0.4
-0.6
1920
1960
Year
2000
1920
1960
Year
2000
2007 Temperature Changes
Compared to 1951-1980
-3
-2.5 -1.5
-1
-.5
-.1
.1
.5
1
1.5
2.5
3.4
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
found melting of Antarctica equivalent
to sea level rise of 0.4 mm/year (2
in/century)
• Zwally, 2005 (satellite radar
altimetry)
 confirmed Antarctica melting
 Greenland ice melting on
exterior, accumulating inland
(higher precipitation)
Melting Glaciers – Mt. Kilimanjaro
Changes in Antarctica Ice Mass
1000
Ice Mass (km3)
800
600
400
200
0
-200
-400
-600
2003
2004
Year
2005
Rise in Sea Levels?
• Present rate is 1.8 ± 0.3 mm/yr (7.4
in/century)
• Accelerating at a rate of 0.013 ± 0.006
mm/yr2
• If acceleration continues, could result
in 12 in/century sea level rise
• Scenarios claiming 1 meter or more
rise are unrealistic
Changing Sea Levels
Relative Sea Level (cm)
Global Temperature Change
20
10
0
-10
-20
1700
Amsterdam, Netherlands
Brest, France
Swinoujscie, Poland
1750
1800
1850
1900
1950
2000
Adapted from IPCC SYR Figure 2-5
20
31
0
30
-20
29
-40
28
-60
-80
27
-100
26
-120
25
450 400 350 300 250 200 150 100 50
Time (KYBP)
0
SST (°C) Tropical Pacific
Sea Level (m)
Sea Levels for 450,000 Years
Increase in Hurricanes?
SST/SPDI (meters3/sec2)
15
Data Unreliable
• Two studies
showed the total number
of hurricanes has not changed
10
• However, the intensity of hurricanes
has increased (more category 4 and 5
hurricanes and cyclones)
• 5Probably due to higher sea surface
August-October
temperatures (more Scaled
energy)
Sea-Surface Temperature
• Difficult to know if this
trend
will Storm
Adjusted
Atlantic
Power Dissipation Index
0continue
1860 1880 1900 1920 1940 1960 1980 2000 2020
How Much Temperature
Increase?
• Some models propose up to 9°C
increase this century
• Two studies put the minimum at 1.5°C
and maximum at 4.5°C or 6.2°C
• Another study puts the minimum at
2.5°C
Wildlife Effects
• Polar Bears
 Require pack ice to live
 Might eventually go extinct in the wild
• Sea turtles
 Breed on the same islands as
their birth
 Could go extinct on some islands
as beaches are flooded
• Other species may go extinct as rainfall
patterns change throughout the world
Effect on Humans
• Fewer deaths from cold, more from
heat
• Decreased thermohaline circulation
 Cooler temperatures in North Atlantic
• CO2 fertilization effect
• Precipitation changes
 Droughts and famine (some areas)
 Expanded arable land in Canada, Soviet Union
Potential Worldwide Precipitation
Changes
-50
-20
-10
-5
5
10
20
50
Drought in Africa
Lake Faguibine
Lake Chad
Cost (Trillons U.S. Dollars)
Cost to Stabilize CO2
Concentrations
1800
1600
1400
1200
1000
800
600
400
200
0
450
550
650
Carbon Dioxide (ppm)
750
Possible Solutions to
Global Warming
Mitigation of Global Warming
• Conservation
 Reduce energy needs
 Recycling
• Alternate energy sources






Nuclear
Wind
Geothermal
Hydroelectric
Solar
Fusion?
Storage of CO2 in Geological Formations
1.
2.
3.
4.
Depleted oil and gas reservoirs
CO2 in enhanced oil and gas recovery
Deep saline formations – (a) offshore (b) onshore
CO2 in enhanced coal bed methane recovery
3b
3a
1
4
2
Adapted from IPCC SRCCS Figure TS-7
Conclusions
• Global warming is happening
• Most warming is probably the result of
human activities
• There will be positive and negative
(mostly) repercussions from global
warming
• The costs to mitigate global warming
will be high – better spent elsewhere?