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The only responsible action to take is immediately to curb CO2 ... The Maunder Minimum (low period in sunspot activity) coincides with the Little Ice Age (Eddy. ... – PowerPoint PPT presentation

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  • Gary A. Ritchie, Ph.D.

Global Warming Scenario
  • The climate is changing.
  • The temperature is getting higher.
  • This is because of human activities (i.e.,
    burning fossil fuels liberates CO2, which
    accumulates trapping heat in the lower atmosphere
    - greenhouse effect).
  • This is bad it will lead to a rise in sea level,
    more frequent and intense storms, increased
    flooding, widespread disruption of agriculture
    and economic hardships.
  • The only responsible action to take is
    immediately to curb CO2 emissions (use less
    energy) - i.e. the US Senate must ratify the
    Kyoto Treaty.

Global Warming Scenario
  • Time Sept. 9, 1999

Global Warming Scenario
  • We are told that virtually all of the scientific
    community now accepts this scenario
  • ...the balance of evidence suggests that there
    is a discernible human influence on global
  • Stuart Eisenstat, Chief U.S. Negotiator at
    Kyoto meeting
  • There is overwhelming evidence that human
    activity is contributing to global warming.
  • Vice President Al Gore (Time, August 1999,
    Page 58)
  • There is ...virtually unanimous agreement among
    scientists that the globe is warming at an
    unacceptable rate.
  • President Bill Clinton, Rose Garden, September

Global Warming Contrarians
  • Many noted and highly respected scientists do not
    believe that we have convincing evidence of any
    significant climate change other than from
    natural causes. These include
  • Dr. Frederick Seitz, Rockefeller University, Past
    President Nat. Acad. of Sciences, Recipient of
    National Medal of Science.
  • Dr. Robert Jastrow, Chairman, Mt. Wilson
    Institute, First Chairman of NASA Lunar
    Exploration Committee, Founder and 20-year
    Director of NASAs Goddard Institute.
  • Dr. Wm. Nierenberg, Director Emeritus Scripps
    Inst. of Oceanography, Member National Acad. of
    Sciences, First Chair of Nat. Adv. Comm. on the
    Oceans and Atmosphere, NASA Advisory Council.
  • .

Global Warming Contrarians
  • Dr. Fred Singer, Prof. (Emeritus) of
    Environmental Science, Univ. Virginia, Disting.
    Res. Prof., Inst. for Space Science and Technol.,
    Disting. Res. Prof., George Mason Univ., Received
    White House Special Commendation. Fellow, AAAS.
  • Dr. Chauncey Starr, Former Dean UCLA Engineering
    School, Past Director AAAS, Recipient of National
    Medal of Science.
  • Dr. Bruce Ames, U. Cal., Berkeley, Biochem. and
    Molecular Biol. Recipient of National Medal of
  • Dr. Robert Balling, Director, Office of
    Climatology, Arizona State University.
  • Dr Willis Hawkins, Sr. VP Lockheed (Ret.), Past
    Chairman Aerospace Advisory Safety Panel, Former
    member NASA Advisory Panel, Recipient National
    Medal of Science.
  • Dr. Sallie Baliunas, Chair, Harvard-Smithsonian
    Center For Astrophysics, Deputy Director, Mt.
    Wilson Observatory.

Global Warming Contrarians
  • Dr. Sylvan Wittwer, Director, Michigan Agr. Expt.
    Station, Chair Agr. Board, National Research
  • Dr. Richard S. Lindzen, Alfred P. Sloan Professor
    of Meteorology, M.I.T.
  • Dr. Thomas Gale Moore, Sr. Fellow, Hoover
  • Dr. Jerry Grey, Amer. Inst. of Aeronautics and
  • Dre. Henry Miller, Stanford University.
  • Dr. Hugh Ellsaesser, Lawrence Livermore National
    Lab (Ret.).
  • Dr. John McCarthy, Stanford University.
  • Dr. H.R. Crane, Member, National Academy of
  • etc.

Global Warming Contrarians
  • There are many others
  • 1992. Statement by Atmospheric Scientists on
    Greenhouse Warming,
  • More than fifty atmospheric physicists and
    meteorologists endorsed a statement reading
    ...there is no consensus about the cause of the
    slight warming observed during the past
    century...sunspot variability, rather than a rise
    in greenhouse gasses, may be responsible for
    the global temperature increases and decreases
    recorded since about 1880... ...the theoretical
    climate models used to predict a future warming
    cannot be relied upon and are not validated by
    the existing climate record... (Singer 1999, p
  • 1996. Leipzig Declaration on Global Climate
  • Over 100 climate scientists from Europe and
    the USA signed a statement which said, in part
    ...there does not exist today a general
    scientific consensus about the importance of
    greenhouse warming from rising levels of carbon
    dioxide. On the contrary, most scientists now
    accept the fact that actual observations from
    earth satellites show no warming whatsoever...
    (Singer 1999, p 41)

Global Warming Contrarians
  • A 1992 Gallup Poll of climate scientists in
    the American Meteorological Society and American
    Geophysical Union asked ...has there been any
    warming to date that could have been caused by
  • No 49
  • Dont know 31
  • Yes 18

Global Warming Contrarians
  • 1997. A petition stating
  • There is no convincing scientific evidence
    that human release of CO2, methane and other
    greenhouse gases is causing or will, in the
    foreseeable future, cause catastrophic heating of
    the Earths atmosphere and disruption of the
    Earths climate ......
  • was signed by over 17,000 Ph.D.s in the
    hard sciences including 2,100 physicists,
    geophysicists, climatologists, meteorologists,
    and environmental scientists who are qualified to
    evaluate the cause of climate change.
  • NY Times (cited in Marshall Inst. News 1(2)
  • Note there has been absolutely no media coverage
    of any of this information.

Is the Earths climate changing?
  • Absolutely!
  • Constant change is a fundamental characteristic
    of climate.
  • The climate has always been changing, and will
    continue to change.
  • Virtually all of this change has occurred before
    the burning of fossil fuels by human societies.

Is the climate getting warmer?
  • This is very difficult to determine for sure,
    because temperature records go back only a little
    longer than 100 years. So indirect methods have
    been developed to reconstruct past climates
    (paleoclimates). Many of these are based on
    various kinds of cores, obtained from
  • Trees (growth rings)
  • Bottoms of lakes or peat bogs (pollen)
  • Deep ocean sediments (plankton, etc.)
  • Ice sheets (trapped gasses, dust particles, etc.)

Is the climate getting warmer?
Global temperatures over the past 850,000 years
as reconstructed
from sea bottom sediments (Shackleton and Opdyke,
Is the climate getting warmer?
  • Surface temperatures in the Sargasso Sea
    (with time resolution of about 50 years) as
    determined by isotope ratios of marine organisms
    in sediment at the bottom of the sea (Kegwin.
    1996. Science 2741504-1509).

Is the climate getting warmer?
  • Direct measurement
  • Surface weather stations.
  • Simple in principle, but vast sampling problems.
    Artifacts such as heat islands can cause
    serious anomalies as large as the overall
    temperature trends (Karl and Jones, 1989. Bull.
    Amer. Meteorol. Soc. 70265-270).

Is the climate getting warmer?
Is the climate getting warmer?
  • Global annual-mean surface air temperature
    change (December-November) based on
    meteorological station network. (Hansen et al.
    1996. Geophysical Res. Let. 231665-1668).

Is the climate getting warmer?
  • Data from NOAA, National Climatic Data Center,
  • (http//

Is the climate getting warmer?
  • Satellites/weather balloons
  • Atmospheric temperature data from NASA
    TIROS-N satellites are believed to be accurate to
    about 0.01C and are corroborated by radiosonde
    weather balloons. Unfortunately these data go
    back only about 20 years so they dont provide
    good long term records. The (corrected) satellite
    data indicate that over the past 20 years the
    temperature of the lower atmosphere has
    fluctuated up and down but that there has been no
    significant warming trend. This conflicts with
    the surface data shown above.

Is the climate getting warmer?
  • Satellite-observed temperatures and balloon
    radiosonde temperatures for the past 20 years
    (World Climate Report 1996). Satellite data are
    corrected for orbital decay and drift (Christy et
    al. 1999. Jour. Geophysical Res. submitted).

Is the climate getting warmer?
  • Conclusions
  • Over the long term there have been large
    fluctuations in global temperature.
  • Over the past century there appears to have been
    a 1F increase in global and northern hemisphere
    surface temperature.
  • However, satellite and balloon data are not in
    agreement with this trend over the past 20 years.

Is the climate getting warmer?
  • Conclusions (continued)
  • If the land data show surface warming (which they
  • and the satellite data show no atmospheric
    warming (which they do),
  • and both records are correct, then
  • the surface warming observed cannot be a
    greenhouse response, because the greenhouse
    effect, by definition, comes from atmospheric
    warming of the surface.

Global warming how worried should we be?
  • If global temperatures are rising, is it because
    of human activities?
  • This is a central question in the global warming
    debate and is very difficult to answer with any
    degree of certainty.
  • The theory of human-caused global warming is
    based on atmospheric CO2 concentration - CO2 is a
    greenhouse gas.
  • Fossil fuel consumption has caused CO2 emissions
    to rise sharply during the past century.
  • This has apparently led to an increase in
    atmospheric CO2 concentrations.
  • Based on this, complex computer climate
    simulation models called General Circulation
    Models (GCMs) have predicted climate warming of
    about 1ºF across the past century.

If global temperatures are rising, is it because
of human activities?
  • Global CO2 emission rates (in 1015 grams of
    carbon per year) between 1880 and 1988 (Rotty and
    Masters. 1985. Atmospheric Carbon Dioxide and the
    Global Carbon Cycle, U.S. DOE, and Boden et al.
    1990. A Compendium of Data on Global Change, Oak
    Ridge National Lab.

If global temperatures are rising, is it because
of human activities?
  • Atmospheric CO2 concentrations from 1764 to
    1988. Open boxes are measurements from ice
    recovered at Siple Station, Antarctica (Raynaud
    and Barnola. 1985. Nature 315309-311), and the
    closed boxes are annual CO2 concentrations
    measured at Mauna Loa, Hawaii (Bacastow et al.
    1985. Jour. Geophysical Res. 90529-540).

If global temperatures are rising, is it because
of human activities?
  • However, these GCM predictions have not been
    borne out by actual temperatures nor have they
    been able to simulate past temperatures.

If global temperatures are rising, is it because
of human activities?
  • GCM-calculated warming due to the increase
    in greenhouse gasses during the past 100 years
    (dashed line), compared to observed temperature
    changes (Seitz, 1994. Global Warming and Ozone
    Hole Controversies).

If global temperatures are rising, is it because
of human activities?
  • There are three fundamental problems with GCMs
  • We do not understand global climate well enough
    to be able to model it satisfactorily.
  • Even if adequate climate models were available,
    we do not have the computing power to run them.
  • There is no way to verify them experimentally.
  • Therefore, GCMs are inadequate in many important
    ways, e.g.
  • They dont accommodate aerosols (dust, volcanic
    emissions) adequately.
  • They dont account very well for cloud effects.
  • They dont handle carbon-ocean exchanges very
  • They assume solar effects are constant.

If global temperatures are rising, is it because
of human activities?
  • What about solar effects, are they really
  • The Maunder Minimum (low period in sunspot
    activity) coincides with the Little Ice Age
    (Eddy. 1976. Science 192 1189-1202).
  • Terrestrial temperature is correlated with
    11-year averages of the sun-spot number (Reid.
    1987. Nature 329 142-143).
  • Baliunas and Jastrow (1990) demonstrated that
    stars undergo changes in brightness of at least
    0.1 during a solar (sun-spot) cycle (Nature
  • Coronal magnetic activity has doubled over the
    past 100 years (Lockwood et al. 1999. Nature
  • Friis-Christensen and Lassen report a striking
    correlation between the length of the solar cycle
    and global temperatures through the period
    between 1880 and 1980 (1991. Science

If global temperatures are rising, is it because
of human activities?
  • Solar activity in terms of sunspot cycle length
    (broken line), and global temperature
    (Friis-Christensen and Lassen. 1991. Science

If global temperatures are rising, is it because
of human activities?
  • An index of the Earths geomagnetic activity (aa
    index), that is driven by sunspot activity, is
    closely correlated with decadal surface
    temperature over the past 110 years (Cliver et
    al. 1998. Geophysical Res. Letters 251035-1038).

If global temperatures are rising, is it because
of human activities?
  • The suns coronal magnetic field correlates with
    the aa index (Cliver et al 1998. Geophys. Res.
    Let. 251035-1038).
  • Earths magnetic field deflects cosmic rays, more
    when the field is strong, especially at high
    latitudes (van Geel et al. 1999. Quart. Sci. Rev.
  • Cosmic rays produce ions when they pass through
    the atmosphere, these provide cloud condensation
    nuclei that produce clouds (Svensmark and
    Friis-Christensen. 1997. J. Atmos. Solar-Terres.
    Physics 591225-1232).
  • Clouds have a cooling effect (Rebetrez and
    Beniston. 1998. Geoph. Res. Lett. 253611-3613).
  • So - A strong coronal magnetic field, which
    deflects more cosmic rays, reduces cloud cover at
    high latitudes, and causes warming.
  • A solar cycle model for Holocene climates was
    developed incorporating these and other effects
    by (Loehle, C.L. Geophy. Res. Letters. In press).
    This model gave a very good fit to Northern
    Hemisphere temperature data of the past 150 years
    including the cooling of the 1950s and 1960s, as
    well as the major climate features of the past
    8,000 years.

If global temperatures are rising, is it because
of human activities?
  • Best fit model (solid line) versus the Northern
    Hemisphere Temperature record (from Jones et al.
    1999. Rev. Geophys. 37173-199) (Loehle 2000.
    Geoph. Res. Lett. In review).

If global temperatures are rising, is it because
of human activities?
  • Millennial-scale climate changes during the past
    60,000 years appear to have been driven primarily
    by small variations in solar activity (vanBeel,
    et al. 1999. Quaternary Sci. Rev. 18331-338).

If global temperatures are rising, is it because
of human activities?
  • Conclusions Is there a CO2-climate warming link?
  • CO2 emissions have increased, as have atmospheric
    CO2 concentrations, over the past century.
  • Temperature has also apparently increased, but
    not at the same rate as CO2 emissions or
    atmospheric CO2 concentrations (most warming
    occurred before the rapid increase in CO2
  • GCM simulations have not always been able to
    recreate past temperature records.
  • There is mounting and compelling evidence that
    solar forcing is a major driver of climate change.

Global warming how worried should we be?
  • If global warming were to occur, would it be all
  • rise in sea level,
  • more frequent and intense storms,
  • increased flooding,
  • widespread disruption of agriculture.

If global warming were to occur, would it be all
  • Increased sea level
  • Two theories
  • Thermal expansion of water and melting land
    glaciers will cause sea level to rise (Wigley and
    Raper, 1992, Nature 57293-300).
  • Increased evaporation from oceans leads to
    increased precipitation over Greenland and
    Antarctica causing a lowering of sea level
    (Oerlemans. 1982. Jour. Climate 21-12)
  • Could go either way.
  • In fact, sea levels have increased by 300 feet
    over the past 18,000 years - probably because of
    the gradual warming of the oceans following the
    last ice age - many millennia before the buildup
    of atmospheric CO2.

If global warming were to occur, would it be all
  • Hurricanes will be more frequent and intense.
  • If a little heated water in the Atlantic can
    create Hurricane Floyd, what storms will global
    warming bring?
  • (Time Magazine, Sept. 27, 1999, p
  • Published data do not support this (Landsea et
    al. 1996).

If global warming were to occur, would it be all
  • Time series of Atlantic basin intense
    hurricanes (sustained surface winds at least 50
    ms-1) and weaker cyclones for 1944-1995.
    Superimposed lines are the best linear fits for
    the intense hurricanes (lower line) and total
    number of cyclones (upper line). (Landsea et al.
    Geophysical Res. Letters 231697-1700).

If global warming were to occur, would it be all
  • Time series of Atlantic basin maximum
    intensity (open symbols) and mean intensity
    (solid symbols). The mean intensity is the
    average of highest sustained surface winds
    averaged by all of the storms for each year. The
    superimposed lines are the best linear fits for
    the maximum intensity (upper line) and mean
    intensity (lower line). (Landsea et al.
    Geophysical Res. Letters 231697-1700).

If global warming were to occur, would it be all
  • More flooding will occur.
  • With warmer temperatures there will be more
    evaporation from water surfaces which will fall
    as rain - hence there will be more flooding.
  • People in Grand Forks, North Dakota, who had to
    move out of their homes because of the flooding,
    dont think global climate change is ... an
    abstraction anymore
  • Vice Pres. Al Gore (New Yorker)

If global warming were to occur, would it be all
  • Record of global precipitation over (over land,
    latitude interval 55 S. to 85 N.), showing a
    general decline since about 1955 (IPCC report,
    1996, p. 155)

If global warming were to occur, would it be all
  • World agriculture will be disrupted.
  • Interestingly, global warmists often
    allude to widespread disruption of agriculture,
    in spite of the fact that abundant evidence
    supports the following facts (Idso, 1995. CO2 and
    the Biosphere. Univ. of Minnesota Wittwer. 1997.
    Food Climate and Carbon Dioxide, CRC Press).
  • Agricultural productivity will most likely
    increase because of increased CO2 in the
    atmosphere. CO2 is the raw material plants use
    for producing sugars, and as atmospheric CO2
    increase, photosynthesis and plant growth
  • There would be other plant benefits such as
    greater resistance to temperature extremes and
    other stresses, better growth at low light
    intensities, improved root/shoot ratios. less
    injury from air pollutants (Policy Review, fall
  • Crops grown under elevated CO2 have higher water
    use efficiency, therefore there may be less need
    for irrigation water.

If global warming were to occur, would it be all
  • Known and predicted benefits of global warming
    are rarely noted. Here are a few
  • Economic impact. Most recent critical analysis is
    Mendelsohn and Neumann (Eds.) 1999. The Impact of
    Global Climate Change on the United States
    Economy, Cambridge Univ. Press. Conclusion
    ...overall, the economic effects of global
    warming are positive and beneficial rather than
    negative and damaging.
  • Cultural impact Throughout recorded history warm
    periods have benefited humans while cold periods
    have brought misery in the form of crop failures,
    malnutrition and increased disease (Moore, 1995).
  • Health impact. Increased atmospheric CO2 may
    improve human health by reducing strain on the
    circulatory system (respiration is controlled by
    the CO2 level in the blood). CO2-stimulated
    deeper breathing may have contributed to the
    significant downturn in circulatory heart disease
    experienced worldwide over the past two decades
    (Idso, 1989).
  • Impact on plants. In terms of Earths history,
    our atmosphere is currently starved for CO2. For
    most of history the atmosphere has contained CO2
    in the thousands of ppm, compared to the current
    350 ppm (Idso, 1989). During the time that
    photosynthesis evolved, atmospheric CO2 was
    nearly 70,000 ppm.

If global warming were to occur, would it be all
  • Life expectancy at various periods in history.
    Peoples living during warm periods (Neolithic,
    Bronze Age, 13th Century England) enjoyed
    relatively long life spans. Shortening of life
    spans during the late 13th and 14th centuries
    coincides with a period of cooler weather (Lamb.
    1977. Climate History and the Future. Princeton
    Univ. Press).

If global warming were to occur, would it be all
  • A compilation of CO2 concentrations (as
    multiples of the pre-industrial value of 280 ppm
    (Redrawn from Berner. 1997. Science 276544-545).

If global warming were to occur, would it be all
  • Conclusions for the most part, fears of global
    environmental or economic catastrophes are not
    well supported by evidence.
  • Sea level may increase, decrease, or remain the
    same during a period of warming this is
    impossible to predict with certainty.
  • There is no evidence to support an increase in
    the frequency or intensity of storms or an
    increase in flooding due to global warming.
  • Global warming and increased CO2 concentrations
    may have positive effects on plant growth,
    agriculture and forestry.
  • Throughout recorded history, human civilizations
    have benefited during warm periods and suffered
    during cold periods.

Global Warming How worried Should We Be?
  • Is curbing CO2 emissions (ratifying the Kyoto
    Treaty) the only responsible course of action for
    the U.S. to take?
  • Delegates from 166 nations met in December, 1997
    in Buenos Aires to implement the Kyoto Treaty on
    climate change. Provisions of the Kyoto Treaty,
    which act to prevent dangerous1 anthropogenic
    interference with the climate system, include
    proposals that would allot each nation a quota
    of greenhouse gas emissions.
  • 1/ dangerous is not defined anywhere in the
    Treaty and there is no scientific indication of
    what concentrations would be dangerous.

Should the U.S. ratify the Kyoto Treaty?
  • Some Key Provisions of Kyoto
  • The U.S. would be required to cut CO2 emissions
    by 7 below 1990 levels by the year 2008-2012.
  • Other developed countries would be required to
    make similar cuts.
  • China, India, Mexico, Brazil, Korea and all other
    developing countries would be totally exempt from
  • The only U.S. military operations that would be
    exempt are multilateral operations under
    control of the U.N.
  • The U.S. Senate will not ratify this treaty
    (Senate Resolution 98, Sponsored by Senators
    Robert Byrd (D-W.V.) and Charles Hagel (R-N.H.),
    passed unanimously on July 17, 1997.
  • However, many actions required to cut U.S.
    emissions are being taken by the Administration
    without Congressional approval.

Should the U.S. ratify the Kyoto Treaty?
Should the U.S. ratify the Kyoto Treaty?
  • In spite of these economic costs Kyoto will not
    control global warming
  • Even if all nations (not just developed nations)
    were required to follow the Kyoto provisions, it
    would barely slow down the rise in atmospheric
  • According to the IPCC Report, a worldwide
    emission cut of 60-80 is required to stabilize
    CO2 at present levels, while Kyoto requires 5.2
    average cut in developed nations only.
  • China, the third largest emitter of CO2, has been
    doubling emissions every 25 year for the past 50
    years and is likely to continue.

Should the U.S. ratify the Kyoto Treaty?
  • The overall climate effect of Kyoto is minuscule
  • The IPCC Report predicts that without Kyoto the
    temperature increase by 2050 will be 1.39C. With
    Kyoto it will be 1.33C, a reduction of only
    0.06C (Parry et al. 1998. Nature 395741).
  • A cut of 30 (six times the Kyoto target) would
    yield only 1.10C, or 0.29C (Parry et al. 1998
    Nature 395741).

Should the U.S. ratify the Kyoto Treaty?
  • The essence of the Kyoto Treaty was captured in a
    recent editorial in the Wall Street Journal
  • The developed countries are being asked to pay
    a huge tax up front to take preventative measures
    of uncertain efficacy against a problem that may
    or may not lie in the Earths future

Should the U.S. ratify the Kyoto Treaty?
  • If limiting CO2 emissions wont work, what course
    of action should the U.S. take?
  • Dont rush to pass misdirected regulations that
    will seriously impact our economy with no
    assurance that they will solve climate problems.
    Once regulations are in place they are nearly
    impossible to rescind.
  • Continue funding research on global climate
    change - but refocus work towards learning how to
    adapt to climate change rather than how to stop
    it, which is probably impossible.
  • Learn to look upon CO2 as a resource rather than
    a pollutant.
  • Rather than trying to stop global warming, we
    should develop long term strategies and policies
    that enable us to adapt to, and benefit from, the
    inevitability of global climate change.

Global warming how worried should we be?
  • Conclusions
  • This issue remains very much in debate - there is
    no consensus.
  • All aspects of global warming, including its
    causes and effects, are cloaked in a huge degree
    of scientific uncertainty.
  • Global warming has become as much a political
    issue as a scientific issue pitting liberals
    against conservatives, Republicans against
    Democrats, socialists against capitalists,
    developing countries against developed countries.
  • We are not being given complete information by
    either our government or popular media sources.
  • The stakes are huge and we had better know what
    we are doing before we begin enacting sweeping
    regulatory initiatives.