Climate Change: Understanding the Science and Developing Strategies for Action

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Climate Change Understanding the Science and
Developing Strategies for Action

• Eugene S. Takle, PhD, CCM
• Professor of Atmospheric Science
• Department of Geological and Atmospheric Sciences
• Professor of Agricultural Meteorology
• Department of Agronomy
• Iowa State University
• Ames, Iowa 50011
• gstakle_at_iastate.edu

Environmental Protection Committee, Iowa House of
Representatives 26 February 2007
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Outline

• Changes in atmospheric carbon dioxide
• Radiative forcing
• Simulations of global climate and future climate
  change
• Climate change for Iowa and the Midwest
• Four components for addressing climate change

Except where noted as personal views or from the
ISU Global Change course or the Iowa
Environmental Mesonet, all materials presented
herein are from peer-reviewed scientific reports
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(No Transcript)
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Pattern repeats about every 100,000 years
Natural cycles
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IPCC Third Assessment Report
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Carbon Dioxide and Temperature
2007 380 ppm
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Carbon Dioxide and Temperature
2050 550 ppm
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Carbon Dioxide and Temperature
Business as Usual 950 ppm
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Carbon Dioxide and Temperature
Business as Usual 950 ppm
?
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http//www.ncdc.noaa.gov/img/climate/research/2006
/ann/glob_jan-dec-error-bar_pg.gif
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Mann, M. E., R. S. Bailey, and M. K. Hughes,
1999 Geophysical Research Letters 26, 759.
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Source IPCC, 2001 Climate Change 2001 The
Scientific Basis
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Source IPCC, 2001 Climate Change 2001 The
Scientific Basis
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IPCC Fourth Assessment Report Summary for Policy
Makers
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El Chichon (1982)
Agung, 1963
Mt. Pinatubo (1991)
At present trends the imbalance 1 Watt/m2 in
2018
Hansen, Scientific American, March 2004
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http//www.ncdc.noaa.gov/img/climate/research/2006
/ann/glob_jan-dec-error-bar_pg.gif
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Natural and anthropogenic contributions to global
temperature change (Meehl et al., 2004).
Observed values from Jones and Moberg 2001. Grey
bands indicate 68 and 95 range derived from
multiple simulations.
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Natural and anthropogenic contributions to global
temperature change (Meehl et al., 2004).
Observed values from Jones and Moberg 2001. Grey
bands indicate 68 and 95 range derived from
multiple simulations.
Natural cycles
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Source Jerry Meehl, National Center for
Atmospheric Research
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Tropical Atlantic Ocean
Hurricane Power Dissipation Index (PDI)
Sea-surface temperature
V
V
V
Emanual, Kerry, 2005 Increasing destructiveness
of tropical cyclones over the past 30 years.
Nature, 436, 686-688.
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Tropical Atlantic Ocean
Hurricane Power Dissipation Index (PDI)
Sea-surface temperature
V
V
V
Emanual, Kerry, 2005 Increasing destructiveness
of tropical cyclones over the past 30 years.
Nature, 436, 686-688.
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Also

• Precipitation in the central US has increased
  since 1970
• Fraction of high-precipitation events has
  increased since 1970
• Extended ice-free periods of lakes has increased
• Milder winters

Groisman et al (2001) Diffenbaugh et
al (2005)
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IPCC Fourth Assessment Report Summary for Policy
Makers
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Source National Center for Atmospheric Research
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The planet is committed to a warming over the
next 50 years regardless of political decisions
Source National Center for Atmospheric Research
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The planet is committed to a warming over the
next 50 years regardless of political decisions
Mitigation Possible
Adaptation Necessary
Source National Center for Atmospheric Research
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IPCC Fourth Assessment Report Summary for Policy
Makers
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IPCC Fourth Assessment Report Summary for Policy
Makers
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IPCC Fourth Assessment Report Summary for Policy
Makers
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Projected Changes for the Climate of Iowa/Midwest
(My tentative assessment)

• Longer frost-free period (high)
• Higher average winter temperatures (high)
• Fewer extreme cold temperatures in winter (high)
• More extreme high temperatures in summer (medium)
• Higher nighttime temperatures both summer and
  winter (high)
• More (10) precipitation (medium)
• More variability of summer precipitation (high)
• More intense rain events and hence more runoff
  (high)
• Higher episodic streamflow (medium)
• Longer periods without rain (medium)
• Higher absolute humidity (high)
• Stronger storm systems (medium)
• Reduced annual mean wind speeds (medium)

Follows trend of last 25 years and projected by
models No current trend but
model suggestion or current trend but models
inconclusive
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Four-Component Approach for Addressing Climate
Change

• Mitigation policies 2050-2100
• Example reduction in GHG emissions
• Adaptation (long-term) 2015-2050
• Example Developing Iowas competitive economic
  advantage
• Adaptation (short-term) 2008-2015
• Example redefining climate normals
  when needed and scientifically justified
• Scenario planning for Iowas Katrina 2007-2100
• Example Multi-year drought, recurrent floods,
  combination of both drought and wildfire

EST personal view
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Climate Adaptation(Short-Term)
If a meteorological variable began departing from
its long-term background near or after 1970 it
may be related to the radiation imbalance and
thereby has a better chance than not of
continuing its new trend over the next 5-10 years.
EST personal view
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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D. Herzmann, Iowa Environmental Mesonet
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North America Regional Climate Change Assessment
Program
Linda O. Mearns, National Center for Atmospheric
Research Principal Investigator

• Raymond Arritt, William Gutowski, Gene Takle,
  Iowa State University
• Erasmo Buono, Richard Jones, Hadley Centre, UK
• Daniel Caya, OURANOS, Canada
• Phil Duffy, Lawrence Livermore National
  Laboratories, USA
• Filippo Giorgi, Jeremy Pal, Abdus Salam ICTP,
  Italy
• Isaac Held, Ron Stouffer, NOAA Geophysical Fluid
  Dynamics Laboratory, USA
• René Laprise, Univ. de Québec à Montréal, Canada
• Ruby Leung, Pacific Northwest National
  Laboratories, USA
• Linda O. Mearns, Doug Nychka, Phil Rasch, Tom
  Wigley, National Center for Atmospheric Research,
  USA
• Ana Nunes, John Roads, Scripps Institution of
  Oceanography, USA
• Steve Sain, Univ. of Colorado at Denver, USA
• Lisa Sloan, Mark Snyder, Univ. of California at
  Santa Cruz, USA

http//www.narccap.ucar.edu/
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Reanalyzed climate , 1979-2000
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For More Information

• For peer-reviewed evidence supporting everything
  you have seen in this presentation, see my online
  Global Change course
• http//www.meteor.iastate.edu/gccourse
• Contact me directly
• gstakle_at_iastate.edu
• Current research on regional climate and climate
  change is being conducted at Iowa State Unversity
  under the Regional Climate Modeling Laboratory
• http//rcmlab.agron.iastate.edu/
• North American Regional Climate Change Assessment
  Program
• http//www.narccap.ucar.edu/
• For this and other climate change presentations
  see my personal website
• http//www.meteor.iastate.edu/faculty/takle/