Download PPT 8.2MB - Department of Geological & Atmospheric Sciences

Climate Change and Impact on
Corn and Grain Quality
Eugene S. Takle
Professor of Agricultural Meteorology, Department of Agronomy
Professor of Atmospheric Science, Department of Geological and
Atmospheric Sciences
Director, Climate Science Initiative
Iowa State University
[email protected]
49th Annual Corn Dry Milling Conference, 29-30 May 2008, Peoria, IL
Outline
• Comparison of natural variability of climate and human
induced climate change
• Projections of future climate change
• Impact of climate change on “regions suitable for rainfed agriculture”, including the US Midwest
• What does this mean for agriculture and corn
production in the US Midwest?
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, 829-843.
Pattern
repeats about
every 100,000
years
Natural cycles
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, 829-843.
IPCC Third Assessment Report
Carbon Dioxide
and Temperature
2008
384 ppm
Carbon Dioxide
and Temperature
2050
550 ppm
Carbon Dioxide
and Temperature
“Business as Usual”
950 ppm
“Business as Usual”
Carbon Dioxide
and Temperature
950 ppm
?
http://www.ncdc.noaa.gov/img/climate/research/2007/ann/global-jan-dec-error-bar-pg.gif
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
IPCC Fourth Assessment Report Summary for Policy Makers
http://www.ncdc.noaa.gov/img/climate/research/2007/ann/glob-jan-dec-error-bar-pg.gif
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 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
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.
Not Natural
Source: Jerry Meehl, National Center for Atmospheric Research
Energy intensive
Reduced Consumption
Energy conserving
IPCC Fourth Assessment Report Summary for Policy Makers
Energy intensive
Reduced Consumption
Energy conserving
The planet is
committed to a
warming over the
next 50 years
regardless of
political decisions
IPCC Fourth Assessment Report Summary for Policy Makers
Energy intensive
Reduced Consumption
Energy conserving
Mitigation
Possible
Adaptation
Necessary
IPCC Fourth Assessment Report Summary for Policy Makers
Suitability
Index for
Rainfed
Agriculture
IPCC 2007
Suitability
Index for
Rainfed
Agriculture
IPCC 2007
Projected changes in
precipitation between
1980-1999 and 20802099 for an energyconserving scenario of
greenhouse gas
emissions
IPCC 2007
Projected Changes* for the
Climate of the Midwest
Temperature
• Longer frost-free period (high)
• Higher average winter temperatures (high)
• Fewer extreme cold temperatures in winter (high)
• Higher nighttime temperatures both summer and winter
(high)
• More freeze-thaw cycles (high)
• Increased temperature variability (high)
Follows trend of last 25 years and projected by models
*Estimated from IPCC reports
Projected Changes* for the
Climate of the Midwest
Precipitation
•
•
•
Most of the increase will come in the first half of the year (wetter
springs, drier summers) (high)
More water-logging of soils (medium)
More variability of summer precipitation (high)
– More intense rain events and hence more runoff (high)
•
Higher absolute humidity (high)
Follows trend of last 25 years and projected by models
*Estimated from IPCC reports
Projected Changes* for the
Climate of the Midwest
Other
•
Reduced wind speeds (high)
•
•
•
•
Increased tropospheric ozone (high)
Accelerated loss of soil carbon (high)
Phenological states are shortened high)
Weeds grow more rapidly under elevated atmospheric CO2
(high)
Weeds migrate northward and are less sensitive to herbicides
(high)
Plants have increased water used efficiency (high)
•
•
Follows trend of last 25 years and projected by models
*Estimated from IPCC and CCSP reports
2007 April
Freeze
Event
Gu, et al, 2008:
The 2007
eastern US
spring freeze:
Increased cold
damage in a
warming world?
Bioscience 58
(3), 261-270.
2007 April Freeze Event
Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world?
Bioscience 58 (3), 261-270.
2007 April
Freeze Event
Gu, et al, 2008:
The 2007
eastern US
spring freeze:
Increased cold
damage in a
warming world?
Bioscience 58
(3), 261-270.
2007 April Freeze Event
Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world?
Bioscience 58 (3), 261-270.
2007 April Freeze Event
Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world?
Bioscience 58 (3), 261-270.
Summary
• Climate change since the 1970s cannot be explained on
the basis of natural variation alone (consensus)
• Greenhouse gases emitted from burning fossil fuels
account for more than half of the current warming
(consensus)
• The warming already introduced will persist for more
than a century (consensus)
• Corn production will encounter some benefits and
numerous challenges (my assessment based on
consensus)
• The US Midwest likely will suffer less adverse effects of
climate change than many other major rain-fed
agricultural areas (my assessment based on consensus)