Global Warming and Climate Change:
An Update
Presentation to
Democratic Women of Clifton
10 March 2013
Dr. Allan R. Hoffman
U.S. Department of Energy (retired)
Outline of Presentation
 Defining global warming and climate change
 The ‘basics’
 Evidence for and implications of climate change
 excerpts from recent testimony to the Congress
 Arguments of those skeptical of significant climate change
 What can we do to alleviate or reverse?
 Concluding remarks
 Contact information
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Definitions (from Wikipedia)
 ‘Global warming’ is the rise in the average temperature of Earth’s
atmosphere and oceans since the late 19th century and its
projected continuation.
 mean surface temperature has increased by 1.4F o since early 20th
century, with about two-thirds occurring since 1980
 these findings recognized by national science academies of all major
industrialized nations
 ‘Climate change’ is a significant and lasting change in the statistical
distribution of weather patterns over periods ranging from
decades to millions of years.
 may be a change in average weather conditions or in the distribution
of weather around the average conditions (i.e., more or fewer
extreme weather events)
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Global Warming ‘Basics’
Think of it as the same process that heats up the interior of your car on a sunny day
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Global Warming - The Temperature Record*
*NASA Goddard Institute for Space Studies (GISS)
-8 warmest years in GISS record have all occurred since 1998
-14 warmest years in record have all occurred since 1990
-2005 and 2010 are planet’s warmest year since reliable measurements began
-warming strongest in Arctic (due to retreat of glaciers, sea ice, permafrost)
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Global Climate Change – Testimony*
 February 13, 2013 briefing for US Senate Environment and
Public Works Committee
 Briefers:
 Dr. Donald Wuebbles, Professor and Atmospheric Scientist,
Department of Atmospheric Sciences, University of Illinois
 Dr. James McCarthy, Professor of Biological Oceanography,
Harvard University
 Dr. J. Marshall Shepherd, President, American Meteorological
Society, and Professor of Geography and Director, Atmospheric Sciences
Program, University of Georgia
 Dr. John M. Balbus, Senior Advisor for Public Health, National Institute of Environmental
Health Sciences and lead author,/human health, 2013 US National Climate Assessment
* see web site of US Senate Environment and Public Works Committee for full testimonies
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Main Points – Dr. Wuebbles
 “The U.S. and the global climate is changing now and this change is apparent across a
wide range of observations. The evidence indicates that most of the climate change of
the past 50 years is primarily due to human activities.”
 “Heavy downpours are increasing in most regions of the U.S., especially over the last
three to five decades. Certain types of other extreme weather events, including heat
waves, and floods and droughts in some regions have become more frequent and intense.
The trends are projected to continue.”
 “Scientific analyses are now indicating a strong link between changing trends in severe
weather events and the changing climate.”
 “There has been an increase in the overall strength of hurricanes and in the number of
strong (Category 4 and 5) hurricanes in the North Atlantic since the early 1980s. The
intensity of the strongest hurricanes is projected to continue to increase as the oceans
continue to warm.”
 “Global sea level has risen by about 8 inches since 1880. It is projected to rise another 1
to 4 feet by 2100. Many coastal areas of the U.S. will be increasingly affected. “
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Main Points – Dr. McCarthy
 “Ocean processes are linked to many types of extreme weather and recent ocean studies
are helping us understand the growing intensity of extreme weather events on land.
Some of the observed changes in the ocean, which only a few decades ago were thought
unimaginable in our lifetimes, are now occurring as result of human-caused climate
change.”
 “The additional heat in the climate system caused by the greenhouse gases that we release
with the burning of fossil fuels and land use practices is now penetrating deep within the
oceans.”
 “For many of us in ocean science the compelling evidence for human-caused climate
change came with the observations of deep ocean warming, the ice core data that
demonstrates linkages between Earth’s past temperature and atmospheric greenhouse
gas content, the acceleration in sea level rise, the abrupt melting of land ice and ice
shelves that had been in place for many thousands of years, and global changes in ocean
chemistry. Such changes in these phenomena can only be consistently explained by an
unusual rate of greenhouse gas release to the atmosphere.”
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Main Points – Dr. Shepherd
 “Key Takeaway Points
This topic is about impact to people--your constituents, my fellow citizens,
my two kids - not just polar bears.
1) Most of the warming of the past 50 years is due to human activity, and
extensive evidence supports this conclusion
2) Climate change is increasing the probability of extreme events, and in some
cases may be strengthening their intensity or increasing their frequency (i.e. we
are loading the dice towards more Sandy or blizzard type storms)
3) There is strong evidence that increases in some types of extremes are linked
to human- induced climate change, notably extreme heat, coastal flooding, and
heavy downpours. For other types of extremes, such as tornadoes, current
evidence is much more limited.”
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Main Points – Dr. Balbus
 “Rising temperature will increase human exposure to mold, microbial
pathogens and infectious diseases. …Studies are indicating that the greatest
heat-related harm may come not from extreme exposure but rather from the
lower but more frequent stress of increasingly hot summer days.”
 “We’ve seen the geographical range of ticks that cover Lyme disease shift
northward, and is predicted to shift further northward in the United States and
Canada….”
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Arguments of the Skeptics
 The Heartland Institute is "the world’s most prominent think tank
promoting skepticism about man-made climate change.” — The Economist,
May 26, 2012
 http://www.heartland.org/issues/environment
 From Wikipedia
 “The Heartland Institute is an American conservative and libertarian public
policy think tank based in Chicago, which states that it advocates free market
policies.”
 “In the 1990s, the group worked with the tobacco company Philip Morris to question
the science linking secondhand smoke to health risks, and to lobby against
government public-health reforms. More recently, the Institute has focused
on questioning the science of human-caused climate change, and was described by
the the New York Times as "the primary American organization pushing climate
change skepticism.“ The Institute has sponsored meetings of climate change
skeptics, and has been reported to promote public school curricula challenging the
scientific consensus on human-caused climate change.”
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What is Heartland Institute Saying?
 “The environmental movement needs voices devoted to sound science and market-
based, rather than government-based, solutions to environmental problems.” (web
site, Heartland Center on Climate and Environmental Policy)
 ‘Roosters of the Apocalypse: How the Junk Science of Global Warming Nearly
Bankrupted the Western World’ (published April 2012 by Heartland Institute)
 it “compares societal belief in climate change to a prophecy that instructed a tribe to
massacre its livestock, resulting in the death of 35,000 people and slavery for the
survivors.” …..”A similar ‘economic suicide’ is looming for the United States of America
if Americans continue to pursue policies restricting the use of fossil fuels in order to avoid
a false climate ‘apocalypse’..” (ClimateWire, April 2, 2012)
 “Human emissions have an impact on the environment, but it is so small that people
and the economy won’t be affected.”, “..a scientific myth..”, ”believing in man-made
global warming-after all the scientific discoveries and revelations that point against
this theory-is more than a little nutty. In fact, some really crazy people use it to
justify immoral and frightening behavior.” (Joe Bast, President, Heartland Institute)
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Heartland Institute (continued)
A billboard featuring the "Unabomber" Ted Kaczynski, which appeared briefly in
the Chicago area in May just before a 3-day Heartland climate change conference,
has caused several companies and organizations to withdraw support for the
Heartland Institute.
- A member of Congress (Rep. Sensenbrenner –WI) threatened to cancel his
speech to the conference before Heartland abruptly ended its billboard campaign.
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What Can We Do?
 In the short term, very little
 the initial response to global warming in the US and European countries was
‘mitigation’, reducing the amount of carbon dioxide going into the atmosphere
 this was notoriously unsuccessful as developing nations with growing economies
became the principal sources of new atmospheric CO2
 ‘Adaptation’ is the current buzzword in global warming/climate change circles
– a recognition that warming continues, climate change is with us and the
world has no choice but to adapt or suffer serious consequences
 even if greenhouse gas emissions stopped today, what has already been placed in the
atmosphere will have long-term effects
 an important impact that is already showing up is that on precipitation patterns which
affect water supplies, and many people see access to clean water as a (the?) principal
21st century environmental, public health and even national security issue
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What Can We Do? (continued)
 In the long term we have to move to low- or zero-carbon fuels as replacements
for hydrocarbon fuels and restrict the release of non-CO2 greenhouse gases
 the historical pattern over the past few centuries has been to move to lower
and lower carbon content fuels – from coat to oil to natural gas to ….
 the ultimate goal for many is a hydrogen-based energy economy, based on
electrolysis of water (H2O), using electricity sources (renewables, nuclear
power) that do not put carbon in the atmosphere
 some people refer to hydrogen as ‘the hydrocarbon without the carbon’
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A Hydrogen Economy
 Is it feasible?
 nuclear power is a feasible, large source of electricity if four problems can be
solved (cost, safety, waste storage, weapons nonproliferation)
 Renewable energy technologies (solar, wind, geothermal, biomass,
hydropower, ocean energy) are feasible as well – see ‘Renewable Electricity
Futures Study’ published by the National Renewable Energy Laboratory
(NREL), June 2012
 key finding: “Renewable electricity generation from technologies that are
commercially available today, in combination with a more flexible electric
system, is more than adequate to supply 80% of total U.S. electricity
generation in 2050 while meeting electricity demand on an hourly basis
in every region of the country.”
 http://www.nrel.gov/analysis/re_futures
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Concluding Remarks
 “For years, prominent religious leaders from around the globe, in
acknowledging the science behind anthropogenic climate change, have
urged governments and citizens to work towards mitigating greenhouse
gas emissions” (‘Faith Organizations and Climate Change’, EESI Fact Sheet,
August 2012)

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A few selected quotes from the Fact Sheet:
 American Baptist Church: “Global warming affects hunger, access to clean water,
environmental stewardship, health and peace. Addressing global warming will make it more
possible for all to live the life of possibility that God intends.”1

Episcopal Church: “[…] the 75th General Convention of The Episcopal Church recognize[s]
that the use of fossil fuels harms air quality and public health and is contributing to changes in
the global climate that threaten the lives and livelihoods of our neighbors around the world; and
[…] the Convention affirm[s] that our Christian response to global warming is a deeply moral
and spiritual issue.

Islam: “Pollution and global warming pose an even greater threat than war… the fight to
preserve the environment could be the most positive way of bringing humanity together.
Environment-related issues ought to be a significant component of educational curricula. It is
the duty of all religious scholars to acquaint themselves with the environmental crisis we are
facing.” — Sheikh Ali Gomaa, Grand Mufti of Egypt (highest official of religious law).
Thank You
 Contact information:
 E-mail: ecosse4@comcast.net
 Tel: (571) 581-4120 (cell)
(703) 437-4332 (home)
And I couldn’t resist:
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