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Transcript
FAITH-BASED REASONING
&
THE GLOBAL WARMING
DEBATE
Katherine K. Hirschboeck, PhD
Laboratory of Tree-Ring Research
University of Arizona
OUTLINE
• The Title
• The Debate
• Scientific Background
•
Addressing the Questions
•
Faith-Based Reasoning
. . . . another perspective
THE TITLE:
Scientific American editorial:
http://www.sciam.com/2001/0601issue/0601rennie.html
The New York Times 2-14-02 article by Andrew C.Revkin “Bush Plan
Expected to Slow, Not Halt, Gas Emission Rise”
Philip E. Clapp, president of the National
Environmental Trust, a private lobbying
group, criticized this approach, saying:
"The president's global warming
proposal appears to be another faithbased initiative: we should have faith
that major corporations will line up to
volunteer cuts in their carbon pollution.
That approach has failed for a decade
now, since the president's father set up
the first voluntary program."
Bush announcing new
Climate Plan 2-14-2002
OUTLINE
• The Title
• The Debate
• Scientific Background
•
Addressing the Questions
•
Faith-Based Reasoning
. . . . another perspective
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
OUTLINE
• The Title
• The Debate
• Scientific Background
•
Addressing the Questions
•
Faith-Based Reasoning
. . . . another perspective
SCIENTIFIC
BACKGROUND
• The Radiation / Energy Balance
• The Greenhouse Effect &
Greenhouse Gases (GHG)
• The Enhanced Greenhouse Effect
• The Climate System
• Detection & Attribution of Change
• Consequences & Impacts
ENERGY BALANCE DIAGRAM
R = (Q + q)(1- a ) - Lu + Ld = H + LE + G
Longwaves
(LW)
The
Electromagnetic
Spectrum
Shortwaves
(SW)
[Not to scale]
Solar short waves
Terrestrial long waves
ultraviolet (UV), visible
infrared (IR)
Clouds
Gas
molecules,
dust,
aerosols
ATMOSPHERE
SOLAR SHORTWAVE
(mostly ultraviolet, visible)
SW BEAMED DIRECTLY TO EARTH’S
SURFACE WHERE IT IS ABSORBED:
Direct solar
radiation
SW REFLECTED BACK TO SPACE:
By
clouds
By
Earth’s
surface
“Albedo”
SW SCATTERED BACK TO SPACE
BY ATMOSPHERE:
By dust,
aerosols, (e.g.
from industrial
& volcanic
emissions),
gas molecules,
etc.
SW SCATTERED DOWN TO EARTH’s
SURFACE where it is absorbed
Diffuse solar
radiation
(reaches the
surface)
SW ABSORBED
IN ATMOSPHERE
BY GASES,
DUST, etc.
Absorbed before it
ever reaches the
surface, e.g.
ultraviolet (UV)
rays absorbed by
stratospheric
ozone gas
molecules
SW ABSORBED
In ATMOSPHERE
BY CLOUDS &
H2O vapor:
Clouds can both
reflect and absorb
solar radiation:
low level clouds tend
to reflect more
TERRESTRIAL
LONGWAVES
infrared (IR)
LW (IR) EMITTED
FROM EARTH’S
SURFACE
ESCAPING TO
SPACE THROUGH
THE “OUTGOING
ATMOSPHERIC
WINDOW”
not absorbed by the atmosphere
IR EMITTED FROM
EARTH’S SURFACE
BUT ABSORBED IN
THE ATMOSPHERE
BY GREENHOUSE
GASES
Greenhouse gas (def) =
any gas that absorbs
infrared (IR) radiation in
the atmosphere
IR EMITTED
FROM
ATMOSPHERE
ESCAPING TO
SPACE
IR energy eventually lost
to space after being
absorbed by atmosphere
IR EMITTED
FROM
ATMOSPHERE
AND RADIATED
BACK TO
SURFACE
WHERE IT IS
ABSORBED
Principal cause of global
warming  IR radiated back
to surface to be absorbed
again
All together now:
The
Greenhouse
Effect
- 30 %
+ 100%
- 70 %
= thermals + evapotranspiration + storage
ENERGY BALANCE
[DRIVES WEATHER & CLIMATE PRCESSES]
Radiative Forcing (def)
A change in the balance between
incoming solar radiation and
outgoing infrared radiation.
Without any radiative forcing, solar
radiation coming to the Earth would
continue to be approximately equal to the
infrared radiation emitted from the Earth.
= in balance
The addition of GREENHOUSE GASES
traps an increased fraction of the
infrared radiation, radiating it back
toward the surface and creating a
warming influence
= a positive (+) radiative forcing
(because incoming solar radiation will exceed
outgoing infrared radiation)
= out of balance
COMPONENTS OF THE GLOBAL CLIMATE SYSTEM
Multiple Natural &
Anthropogenic Forcings
FEEDBACK MECHANISM (def)
A mechanism that connects one aspect of a
system to another. The connection can be either
amplifying (+ positive feedback) or moderating /
self-regulating (- negative feedback).
Climate feedback =
An atmospheric, oceanic, terrestrial, or other
process that is activated by climate changes
induced by changes in radiative forcing.
Climate feedbacks may increase (+ positive feedback)
or diminish (- negative feedback) the magnitude of the
direct climate change.
A Negative Climate Feedback
(self regulating)
Earth heats up
 Earth radiates more LW out
 Earth cools down again -
A Positive Climate Feedback
(amplifying)
Earth heats up
snow and ice melt earlier, glaciers diminish
 surface reflectivity (albedo)
decreases
 more Solar SW gets
absorbed
 Earth heats up
MORE +
MULTIPLE FEEDBACKS
(e.g., snow / ice, water vapor,
clouds, etc.)
Detection &
Attribution of
Change
Data & Tools
Used:
• Instrumental measurements
• Determining past (paleo) climate from
natural archives (e.g. tree rings, ice cores)
• Remote sensing of the environment
• Modeling
CLIMATE CHANGES OF THE PAST via
TREE RINGS & other PROXY Records
• Calibration of “proxy” record with instrumental climate
record
• Statistical reconstructions of past temperature and
precipitation values
• CONVERGENCE of evidence from multiple proxy
sources
REMOTE SENSING OF THE
ENVIRONMENT
MODEL RESULTS & PROJECTIONS
Latitude-Longitude grid for a typical
atmospheric general circulation model
(GCM)
OUTLINE
• The Title
• The Debate
• Scientific Background
•
Addressing the Questions
•
Faith-Based Reasoning
. . . . another perspective
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
Greenhouse Gas (def)
Any gas that absorbs infrared (IR) radiation in
the atmosphere.
Greenhouse gases include:
• water vapor (H2O)
• carbon dioxide (CO2)
• methane (CH4)
• nitrous oxide (N2O)
• ozone (O3)
• other trace gases such as CFCs, halogenated
fluorocarbons (HCFCs), perfluorinated carbons
(PFCs), & hydrofluorocarbons (HFCs)
Are the GHG’s increasing due
to human activities?
Carbon
Dioxide
CO2
Data from ice cores
CO2 concentrations are rising at an increasing rate; since the
Industrial Revolution, higher than any period during the last
10,000 years. More abundant now than at any time during the
400,000 year ice core record
Methane
CH4
More abundant
now than at any
time during the
400,000 year ice
core record
Nitrous
Oxide N2O
Concentration has
increased ~ 13% in
past 200 years.
GHG’s have different radiative forcing
contributions due to their IR absorption
properties, relative concentration, and
residence times in the atmosphere
The contribution from each of the human-made GHG’s to the
change in “radiative forcing” (e.g., to warming) from 1980 to
1990.
(Based on model results)
Anthropogenically Enhanced Greenhouse Effect
= out of balance
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
The most comprehensive source of information on
Global Climate Change -- the IPCC
• The role of the IPCC is to assess the
scientific, technical and socio-economic
information relevant for the understanding of
the risk of human-induced climate change.
• It does not carry out new research nor
does it monitor climate related data.
• It bases its assessment mainly on published
and peer-reviewed scientific technical
literature.
The IPCC has three working groups and a Task Force:
Working Group I -- assesses the scientific
aspects of the climate system and climate
change.
Working Group II -- addresses the vulnerability
of socio-economic and natural systems to
climate change, negative and positive
consequences of climate change, and options
for adapting to it.
Working Group III -- assesses options for
limiting greenhouse gas emissions and
otherwise mitigating climate change.
[The Task Force on National Greenhouse Gas Inventories -oversees the National Greenhouse Gas Inventories Program]
IPCC’s “CLIMATE CHANGE 2001” Reports
http://www.ipcc.ch/
“Climate change” in IPCC usage refers to any change
in climate over time, whether due to natural variability
or as a result of human activity.
• 122 Coordinating Lead Authors and Lead Authors
• 515 Contributing Authors
• 21 Review Editors
• 420 Expert Reviewers
Some of the evidence for an observed change in
temperature summarized in the IPCC reports:
= warming
= cooling
= warming
= cooling
Gray = error bars
Black line = smoothed trend
Disappearing
tropical
glaciers:
the “canary in
the coal mine”
In 1978, the Qori Kalis
Glacier looked like
this, flowing out from
the Quelccaya Ice
Cap in the Peruvian
Andes Mountains.
In 2000, the view of
Qori Kalis has
changed
dramatically with a
massive 10-acre
lake forming at the
ice margin.
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
WARMEST DECADE of the millennium was the 1990s
researchers now say with a fairly high degree of
confidence, based on direct and indirect temperature
readings (red).
Scientists also say with the same degree of confidence
that CO2 levels (measured in ice cores) are the highest in
20 million years. (blue)
GHG forcing
SCIENTIFIC UNCERTAINTY
synonyms UNCERTAINTY, SKEPTICISM, mean lack of
sureness about someone or something.
UNCERTAINTY may range from a falling short of
certainty to an almost complete lack of conviction or
knowledge especially about an outcome or result
<assumed the role of manager without hesitation or
uncertainty>.
SKEPTICISM implies unwillingness to believe without
conclusive evidence <an economic forecast greeted
with skepticism>.
Source: Merriam-Webster Collegiate Dictionary
Global
Warming
Skeptics
http://www.oism.org/pproject/
Satellite
measurements
of air
temperature
differ somewhat
from Earth
surface
measurements
http://science.nasa.gov/headlines/y2000/ast21jul_1m.htm
UNIQUE FEATURE OF IPCC 2001 REPORTS:
Judgmental estimates of confidence in the
report’s results / conclusions:
• virtually certain (greater than 99% chance that a
result is true)
• very likely (90-99% chance);
• likely (66-90% chance);
• medium likelihood (33-66% chance);
• unlikely (10-33% chance);
• very unlikely (1-10% chance);
• exceptionally unlikely (less than 1% chance).
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
INERTIA in the CLIMATE SYSTEM:
LIKELY CONSEQUENCES / IMPACTS:
• Benefits to agriculture & forestry in the near
term due to CO2 “fertilization” effect
• Possible droughts in semi-arid regions, Great
Plains
• Reduction in water supply in western U.S.,
where dependent on amount of snow pack &
timing of spring runoff
• Higher sea levels could make coastal regions
more vulnerable to flooding and storm damage
• Ecosystems may be greatly affected
THE DEBATE QUESTIONS
(actually several debates)
(1) Are Greenhouse Gas (GHG)
concentrations in the atmosphere
increasing due to anthropogenic sources?
(2) Is the Earth’s Temperature Increasing?
(3) Is there a cause and effect relationship
between (1) and (2) above?
(4) What are the projections for the future &
the consequences of global warming?
(5) What can/should be done about the
problem?
Based on
1990 start
CO2 Production
Scenarios
d
a. Drops immediately to 0
b. Decreases by 2% / yr
c
a
Resulting
Atmospheric CO2
Concentrations
for scenarios a,b,c,
&d
b
c. Remains constant
d. Increase continues
“business as usual”
USA votes “no” to
Kyoto protocol-based
climate treaty, 2001
“Climate Change
Science: An
Analysis of Some
Key Questions”
National Academy of
Sciences panel study, 2001
Panel study in response to a written
request by White House to the
National Academy of Sciences for:
“assistance in identifying the areas in
the science of climate change where
there are the greatest certainties and
uncertainties” . . . and . . .
“ views on whether there are any
substantive differences between the
IPCC Reports and the IPCC
summaries [ for policy makers ].”
http://books.nap.edu/html/climatechange/
National Academy of Science Report
The panel conclusions:
• GHG are accumulating in the Earth's atmosphere as a
result of human activities . . . .
• We cannot rule out that some significant part of these
changes are also a reflection of natural variability. . . .
• . . . because there is considerable uncertainty in current
understanding of how the climate system varies naturally
and reacts to emissions of greenhouse gases and aerosols,
current estimates of the magnitude of future warming
should be regarded as tentative and subject to future
adjustments (either upward or downward). . . ."
• While the full implications of climate change remain
unknown, the panel "generally agrees with the assessment
of human-caused change presented in the IPCC Working
Group I scientific report."
IPCC Scientific Convergence / Consensus
U.S. Policy Response
Feb 14, 2002
Reduce greenhouse gas
“intensity” by 18% over next
decade (= volume of GHG
emissions / gross domestic
product)
inducements instead of
requirements; tax breaks;
prospect of a future emissions
credits to encourage industry
and individuals to voluntarily
reduce emissions
OUTLINE
• The Title
• The Debate
• Scientific Background
•
Addressing the Questions
•
Faith-Based Reasoning
. . . . another perspective
American
Geophysical Union
(AGU)
study in 1998
http://www.agu.org/sci_soc/attitude_study.html
AGU STUDY CONCLUSIONS
“public paralysis & frustration”
“Our research suggests that there are a number of reasons why
people may be stuck:
1. Most people do not really understand global warming.
2. No accepted source of information.
“Clearly the scientific community has not conveyed a sense of unanimity on
the subject of global warming. As a result of the fact that they have not
heard a clear scientific voice on this subject, people turn to anecdotal and
impressionistic evidence as to whether there is such a thing as global
warming.”
3. The real cause is human greed.
“The biggest factor that derails any kind of consensus about dealing with
global warming is the analysis that people have of the underlying cause of
global warming. While our focus group respondents tended to say that
global warming is caused by deforestation and pollution, they were also
quick to point out that the underlying cause is human greed and moral
corruption. Moreover, they believed that, as far as these factors are
concerned, "the toothpaste is out of the tube," and we are unlikely to
reverse these trends in the near future.”
AGU STUDY CONCLUSIONS
“public paralysis & frustration”
“When thinking about global warming, in other words,
our respondents typically saw it as being driven by
humans who are unwilling to do the right thing, that is
a seemingly irreversible deterioration in moral values.
What they said, over and over again, was that people
have become more self-centered, greedy and
materialistic, and as a result, the society is inevitably
pushed toward more consumption, which in turn
causes more pollution and exacerbates the trend
toward global warming.”
AGU STUDY CONCLUSIONS
“public paralysis & frustration”
“Our respondents, then, seemed to have hit a wall. They
said they care deeply about global warming, but their
concern did not translate into any forward motion.
As they thought about the problem, they seemed to run
into brick walls, characterized by lack of clear
knowledge, seemingly irreversible causes, and a
problem with no real solution.
As a result they were frustrated and eager for a solution
but unsure of which way to go. “
http://www.usccb.org/sdwp/international/globalclimate.htm
“As people of faith, we are convinced that "the earth is the Lord's
and all it holds" (Ps 24:1). . . . We believe our response to global
climate change should be a sign of our respect for God's creation.
We enter this debate not to embrace a particular treaty, nor to urge
particular technical solutions, but to call for a different kind of
national discussion. Much of the debate on global climate change
seems polarized and partisan.
Science is too often used as a weapon, not as a source of wisdom.
Various interests use the airwaves and political process to
minimize or exaggerate the challenges we face.
The search for the common good and the voices of poor people
and poor countries sometimes are neglected.”
“At its core, global climate change is not about
economic theory or political platforms, nor about
partisan advantage or interest group pressures. It is
about the future of God's creation and the one human
family.
The dialogue and our response to the challenge of
climate change must be rooted in the virtue of
prudence . . . . Although debate continues about the
extent and impact of this warming, it could be quite
serious . . . . Consequently, it seems prudent not only
to continue to research and monitor this phenomenon,
but to take steps now to mitigate possible negative
effects in the future.
Stewardship
“United States bears a special responsibility in its stewardship
“
Scientific Knowledge and the Virtue of Prudence
“The virtue of prudence is paramount in addressing climate
change.“
“ Prudence is not, as popularly thought, simply a cautious and
safe approach to decisions. . . . it is a thoughtful, deliberate,
and reasoned basis for taking or avoiding action to achieve a
moral good.
• intelligence applied to our actions.
• aids in the shaping of the community's conscience.
• moves us to adopt courses of action to protect the
common good
Climate Change and Catholic Social Teaching
• The Universal Common Good
• Stewardship of God's Creation and the Right to Economic
Initiative and Private Property
• Protecting the Environment for Future Generations
• Population and Authentic Development
• Caring for the Poor and Issues of Equity
The Public Policy Debate and Future Directions
“Catholic social teaching calls for bold and generous action on
behalf of the common good.”
"Interdependence," as Pope John Paul II has written, "must be
transformed into solidarity. . . . Surmounting every type of
imperialism and determination to preserve their own
hegemony, the stronger and richer nations must have a
sense of moral responsibility for the other nations, so that a
real international system may be established which will rest
on the foundation of the equality of all peoples and on the
necessary respect for their legitimate differences.“
Pastoral Constitution on the Church in the Modern World
(Gaudium et Spes), no. 39
Finally, we wish to emphasize the need for personal conversion and
responsibility:
• Choices and lifestyles
• Reexamine a culture that prizes the consumption of material
goods.
• Conserve energy, prevent pollution, and live more simply
“In [the] spirit of praise and thanksgiving to God for the wonders of
creation, we Catholic bishops call for a civil dialogue and prudent
and constructive action to protect God's precious gift of the earth's
atmosphere with a sense of genuine solidarity and justice for all
God's children.”
UNCERTAINTY IN
AMOUNT OF
WARMING
FAITH (def)
1 a : allegiance to duty or a person : LOYALTY
1 b (1) : fidelity to one's promises (2) : sincerity of
intentions
2 a (1) : belief and trust in and loyalty to God
(2) : belief in the traditional doctrines of a religion
2 b (1) : firm belief in something for which there is no
proof
(2) : complete trust
3 : something that is believed especially with strong
conviction; especially : a system of religious beliefs
Source: Merriam-Webster Collegiate Dictionary
Synonyms: BELIEF, FAITH, CREDENCE, mean
assent to the truth of something offered for
acceptance.
BELIEF may or may not imply certitude in the
believer <my belief that I had caught all the
errors>.
FAITH almost always implies certitude even where
there is no evidence or proof <an unshakable faith
in God>.
CREDENCE suggests intellectual assent without
implying anything about grounds for assent <a
theory now given credence by scientists>.
Source: Merriam-Webster Collegiate Dictionary
• As an act of solidarity . . . the United States should lead the
developed nations in . . . the sustainable economic
development of poorer nations & help build their capacity to
ease climate change.
• Since our country's involvement is key . . . we call on our
people and government to recognize the seriousness of the
global warming threat & to develop effective policies that will
diminish the possible consequences of global climate change
• We also hope that the United States will continue to
undertake reasonable and effective initiatives for energy
conservation and the development of alternate renewable and
clean-energy resources. . . . Our hope is that these
technologies along with other resources can be shared with
developing countries.
• Within the United States, public policy should assist
industrial sectors and workers especially impacted by climate
change policies, & it should offer incentives to corporations to
reduce greenhouse gas emissions and assistance to workers
affected by these policies.
THE UNKNOWNS IN GLOBAL WARMING RESEARCH
DON'T HAVE TO BE SHOWSTOPPERS
Scientific American October 2001
”Denying uncertainty makes life so much easier, as many have
discovered when it comes to climate change. Between skeptics'
insistence that global warming is just hot air and radical
environmentalists' advice to start selling the beachfront property,
responses to climate change tend to be predicated on claims of
absolute knowledge. Who wants to deal with the messy reality?
There is plenty of evidence that temperatures are rising and will
continue to do so but lots of uncertainty about the details and
amount of future change. The good news is that politicians are
finally confronting the messiness. . . .
The bad news is that uncertainty still paralyzes discussion,
especially in the U.S. Scientists naturally generate a range of
results. Not all of these results are equally likely to be true, and
none is definitive, but people tend to latch onto those that suit their
preconceptions. “
http://www.sciam.com/2001/1001issue/1001scicit1.html
National Academy of Science Study Summary:
• Anthropogenic GHG’s are increasing (except for CFCs)
• Other anthropogenic emissions (aerosols, CO, black
carbon soot) are also affecting climate w/ + and – forcings
• GHG removal times/residence times vary from 10 yrs (CH4)
to > 100 yrs (CO2) to > 1000 yrs (PFCs)
• Global mean surface air temperature has warmed
between 0.4 – 0.8 °C (0.7-1.5 °F) in 20th century; temporal
irregularities and surface vs. troposphere disparities have
occurred and are not completely understood.
• Most of the observed warming of the last 50 yrs is likely to
have been due to the increase in GHG concentrations (IPCC)
National Academy of Science Study Summary
• Over the next 100 yrs, scenarios indicated that globally
average surface temperatures will increase in the range of
1.4 – 5.8 ° C (2.5 – 10.4 ° F) relative to 1990.
• Predicted warming is larger over higher latitudes, esp.
during winter & spring.
• Rainfall rates & frequency of heavy precipitation events are
predicted to increase, esp over high latitudes
• Higher evaporation rates will accelerate drying of soils,
lower relative humidities, and higher daytime temperatures,
esp. in warm season
• Water vapor and ice-albedo feedback processes will
amplify the simulated GHG forcing by a factor of 2.5
• Uncertainties remain on cloud feedback response
• IPCC reports & Summaries for Policy Makers – slight
difference in emphasis in WG II & III reports