1. Climate Change and Animal Agriculture: Thinking Beyond the Spherical Steer
Eugene S. Takle
Professor of Atmospheric Science
Department of Geological and Atmospheric Sciences
Professor of Agricultural Meteorology
Department of Agronomy
Iowa State University
Ames, Iowa 50011
Animal Think Tank, Iowa State University
26 February 2007

2. 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
Impacts of climate change on animal agriculture
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

3. CO2, CH4 and temperature records from Antarctic ice core data
Source: Vimeux, F., K.M. Cuffey, and Jouzel, J., 2002, "New insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction", Earth and Planetary Science Letters, 203,

4. CO2, CH4 and temperature records from Antarctic ice core data
Source: Vimeux, F., K.M. Cuffey, and Jouzel, J., 2002, "New insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction", Earth and Planetary Science Letters, 203,
Pattern repeats about every 100,000 years
Natural cycles

5. IPCC Third Assessment Report

6. Carbon Dioxide and Temperature
2007
380 ppm

7. Carbon Dioxide and Temperature
2050
550 ppm

8. Carbon Dioxide and Temperature
“Business as Usual”
950 ppm

9. Carbon Dioxide and Temperature
“Business as Usual”
950 ppm ?

10. E. S. Takle, ISU Global Change course

11. IPCC Fourth Assessment Report Summary for Policy Makers

13. Mann, M. E., R. S. Bailey, and M. K. Hughes, 1999: Geophysical Research Letters 26, 759.

14. Natural and anthropogenic contributions to global temperature change (Meehl et al., 2004). Observed values from Jones and Moberg Grey bands indicate 68% and 95% range derived from multiple simulations.

15. Natural and anthropogenic contributions to global temperature change (Meehl et al., 2004). Observed values from Jones and Moberg Grey bands indicate 68% and 95% range derived from multiple simulations.
Natural cycles

16. Source: Jerry Meehl, National Center for Atmospheric Research
From Jerry Meehl
This slide shows the time evolution of globally averaged surface air
temperature from multiple ensemble simulations of 20th century climate
from the NCAR Parallel Climate Model (PCM) compared to observations.
The simulations start in the late 19th century, and continue to the year
The temperature scale at left is in degrees Centigrade, and
temperature anomalies are calculated relative to a reference period
averaged from 1890 to The black line shows the observed data, or
the actual, recorded
globally averaged surface air temperatures from the past century. The
blue and red lines are the average of four simulations each from the
computer model. The pink and light blue shaded areas depict the range
of the four simulations for each experiment, giving an idea of the
uncertainty of a given realization of 20th century climate from the
climate model. The blue line shows the average from the four member
ensemble of the simulated time evolution of globally average surface air
temperature when only "natural" influences (solar variability and
volcanic eruptions) are included in the model. Therefore, the blue
line represents what the model says global average temperatures would
have been if there had been no human influences. The red line shows the
average of the four member ensemble experiment when natural forcings AND
anthropogenic influences (greenhouse gases including carbon dioxide,
sulfate aerosols from air pollution, and ozone changes) are included in
the model. Note that this model can reproduce the actual, observed data
very well only if the combined effects of natural and anthropogenic
factors are included. The conclusion that can be drawn is that
naturally occuring influences on climate contributed to most of the
warming that occurred before WWII, but that the large observed
temperature increases since the 1970s can only be simulated in the model
if anthropogenic factors are included.
This confirms the conclusion of the IPCC Third Assessment Report that
most of the warming we have observed in the latter part of the 20th
century has been due to human influences.
Source: Jerry Meehl, National Center for Atmospheric Research

17. Source: IPCC, 2001: Climate Change 2001: The Scientific Basis

18. Source: IPCC, 2001: Climate Change 2001: The Scientific Basis

19. At present trends the imbalance = 1 Watt/m2 in 2018
El Chichon (1982)
Agung, 1963
Mt. Pinatubo (1991)
At present trends the imbalance = 1 Watt/m2 in 2018
Hansen, Scientific American, March 2004

20. Source: Jerry Meehl, National Center for Atmospheric Research
From Jerry Meehl
This slide shows the time evolution of globally averaged surface air
temperature from multiple ensemble simulations of 20th century climate
from the NCAR Parallel Climate Model (PCM) compared to observations.
The simulations start in the late 19th century, and continue to the year
The temperature scale at left is in degrees Centigrade, and
temperature anomalies are calculated relative to a reference period
averaged from 1890 to The black line shows the observed data, or
the actual, recorded
globally averaged surface air temperatures from the past century. The
blue and red lines are the average of four simulations each from the
computer model. The pink and light blue shaded areas depict the range
of the four simulations for each experiment, giving an idea of the
uncertainty of a given realization of 20th century climate from the
climate model. The blue line shows the average from the four member
ensemble of the simulated time evolution of globally average surface air
temperature when only "natural" influences (solar variability and
volcanic eruptions) are included in the model. Therefore, the blue
line represents what the model says global average temperatures would
have been if there had been no human influences. The red line shows the
average of the four member ensemble experiment when natural forcings AND
anthropogenic influences (greenhouse gases including carbon dioxide,
sulfate aerosols from air pollution, and ozone changes) are included in
the model. Note that this model can reproduce the actual, observed data
very well only if the combined effects of natural and anthropogenic
factors are included. The conclusion that can be drawn is that
naturally occuring influences on climate contributed to most of the
warming that occurred before WWII, but that the large observed
temperature increases since the 1970s can only be simulated in the model
if anthropogenic factors are included.
This confirms the conclusion of the IPCC Third Assessment Report that
most of the warming we have observed in the latter part of the 20th
century has been due to human influences.
Source: Jerry Meehl, National Center for Atmospheric Research

21. 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,

22. 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,

23. IPCC Fourth Assessment Report Summary for Policy Makers

24. 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

25. Source: National Center for Atmospheric Research

26. The planet is committed to a warming over the next
50 years regardless of
political decisions
Source: National Center for Atmospheric Research

27. 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

28. IPCC Fourth Assessment Report Summary for Policy Makers

29. IPCC Fourth Assessment Report Summary for Policy Makers

30. IPCC Fourth Assessment Report Summary for Policy Makers

31. 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

32. Four-Component Approach for Addressing Climate Change
Mitigation policies:
Example: reduction in GHG emissions
Adaptation (long-term):
Example: Developing Iowa’s competitive economic advantage
Adaptation (short-term):
Example: redefining climate “normals” when needed and scientifically justified
Scenario planning for Iowa’s “Katrina”:
Example: Multi-year drought, recurrent floods, combination of both; drought and wildfire
EST personal view

33. Adaptation Tactics
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

34. D. Herzmann, Iowa Environmental Mesonet

35. D. Herzmann, Iowa Environmental Mesonet

36. D. Herzmann, Iowa Environmental Mesonet

37. D. Herzmann, Iowa Environmental Mesonet

38. D. Herzmann, Iowa Environmental Mesonet

39. D. Herzmann, Iowa Environmental Mesonet

40. D. Herzmann, Iowa Environmental Mesonet

41. D. Herzmann, Iowa Environmental Mesonet

42. 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

43. 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

48. Kansas

49. Kansas

50. Kansas

51. Kansas

52. Kansas

53. Kansas

54. Kansas

55. Kansas

56. Kansas

57. Kansas

58. Temperature-Humidity Index
THI = (Dry bulb temperature oC) + (0.36* dew point temperature oC) +41.2
THI threshold values:
- Dairy cows 72
Mild 72-79
Moderate 80-89
Severe 90-98
Dangerous >98
- Beef cattle 72 – 75
- Swine 72 – 74
- Poultry 70 – 78

59. Impact of Animal Agriculture on Climate Change
Production of greenhouse gases: methane (digestion, wastes), nitrous oxide and carbon dioxide (growing of feedstuff)
Impact of waste materials on carbon and nutrient cycles
Altered land use patterns

60. Impact of Climate Change on Animal Agriculture
Reduced weight gain of meat animals in summer, maybe increased in winter
More freeze-thaw cycles (animal health)
Reduced milk production for dairy cows
Reduced breeding successes
Altered vectors for pathogens
Reduced nutritional value of feed due to altered C:N ratios

61. For More Information
For peer-reviewed evidence supporting everything you have seen in this presentation, see my online Global Change course:
Contact me directly:
Current research on regional climate and climate change is being conducted at Iowa State Unversity under the Regional Climate Modeling Laboratory
North American Regional Climate Change Assessment Program
For this and other climate change presentations see my personal website: