GLOBAL WARMING

1
GLOBAL WARMING!

• HOW WORRIED SHOULD WE BE?
• Gary A. Ritchie, Ph.D.

2
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.

3
Global Warming Scenario

• Time Sept. 9, 1999

4
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
  climate
• 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
  1998

5
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.
• .

6
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
  Science
• 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.

7
Global Warming Contrarians

• Dr. Sylvan Wittwer, Director, Michigan Agr. Expt.
  Station, Chair Agr. Board, National Research
  Council.
• Dr. Richard S. Lindzen, Alfred P. Sloan Professor
  of Meteorology, M.I.T.
• Dr. Thomas Gale Moore, Sr. Fellow, Hoover
  Institute.
• Dr. Jerry Grey, Amer. Inst. of Aeronautics and
  Astronautics.
• 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
  Sciences.
• etc.

8
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
  40).
• 1996. Leipzig Declaration on Global Climate
  Change
• 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)

9
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
  humans?
• No 49
• Dont know 31
• Yes 18

10
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)
  1998).
• Note there has been absolutely no media coverage
  of any of this information.

11
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.

12
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.)

13
Is the climate getting warmer?
Global temperatures over the past 850,000 years
as reconstructed
from sea bottom sediments (Shackleton and Opdyke,
1973.
Quaternary
Research
339-55).
14
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).

15
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).

16
Is the climate getting warmer?
17
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).

18
Is the climate getting warmer?

• Data from NOAA, National Climatic Data Center,
• (http//www.noaa.gov/noaatvd/ncdc/glance/noaavstop
  8.html)

19
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.

20
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).

21
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.

22
Is the climate getting warmer?

• Conclusions (continued)
• If the land data show surface warming (which they
  do)
• 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.

23
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.

24
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.

25
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).

26
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.

27
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).

28
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
  well.
• They assume solar effects are constant.

29
If global temperatures are rising, is it because
of human activities?

• What about solar effects, are they really
  constant?
• 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
  348520-523).
• Coronal magnetic activity has doubled over the
  past 100 years (Lockwood et al. 1999. Nature
  399437-439).
• 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
  254698-700).

30
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
  254698-700).

31
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).

32
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.
  18331-338).
• 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.

33
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).

34
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).

35
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
  emissions).
• 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.

36
Global warming how worried should we be?

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

37
If global warming were to occur, would it be all
bad?1

• 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.

38
If global warming were to occur, would it be all
bad?

• 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
  39).
• Published data do not support this (Landsea et
  al. 1996).

39
If global warming were to occur, would it be all
bad?

• 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).

40
If global warming were to occur, would it be all
bad?

• 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).

41
If global warming were to occur, would it be all
bad?

• 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)

42
If global warming were to occur, would it be all
bad?

• 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)

43
If global warming were to occur, would it be all
bad?

• 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
  increase.
• 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
  1992).
• Crops grown under elevated CO2 have higher water
  use efficiency, therefore there may be less need
  for irrigation water.

44
If global warming were to occur, would it be all
bad?

• 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.

45
If global warming were to occur, would it be all
bad?

• 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).

46
If global warming were to occur, would it be all
bad?

• A compilation of CO2 concentrations (as
  multiples of the pre-industrial value of 280 ppm
  (Redrawn from Berner. 1997. Science 276544-545).

47
If global warming were to occur, would it be all
bad?

• 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.

48
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.

49
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
  restrictions.
• 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.

50
Should the U.S. ratify the Kyoto Treaty?
51
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
  GHG.
• 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.

52
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).

53
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

54
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.

55
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.