recent observed and projected future climate trends for the midwest: agricultural impacts eugene s....
TRANSCRIPT
Recent Observed and Projected Future Climate Trends for the Midwest:
Agricultural Impacts
Recent Observed and Projected Future Climate Trends for the Midwest:
Agricultural Impacts
Eugene S. TakleDirector, Climate Science Initiative
Professor of Atmospheric Science
Department of Geological and Atmospheric Sciences
Professor of Agricultural Meteorology
Department of Agronomy
Iowa State University
Ames, Iowa 50011
Eugene S. TakleDirector, Climate Science Initiative
Professor of Atmospheric Science
Department of Geological and Atmospheric Sciences
Professor of Agricultural Meteorology
Department of Agronomy
Iowa State University
Ames, Iowa 50011
Climate Change and Its Impacts on Food Production and BiofuelsAmes, Iowa
2 March 2010
“I hear so many conflicting views on
climate change, I don’t know what or
who to believe”
“I hear so many conflicting views on
climate change, I don’t know what or
who to believe”Soybean producer from NE Iowa
Established on 3 March 1863 by Abraham Lincoln
Act of Incorporation: to "investigate, examine, experiment, and report upon any subject of science or art" whenever called upon to do so by any department of the government
June 2001: National Academy of Sciences Committee on the Science of Climate Change concludes that human-induced global warming is a serious issue [http://www.nasonline.org/site/DocServer/speech2002.pdf?docID=121]
Established on 3 March 1863 by Abraham Lincoln
Act of Incorporation: to "investigate, examine, experiment, and report upon any subject of science or art" whenever called upon to do so by any department of the government
June 2001: National Academy of Sciences Committee on the Science of Climate Change concludes that human-induced global warming is a serious issue [http://www.nasonline.org/site/DocServer/speech2002.pdf?docID=121]
US National Academy of Sciences
http://www.nasonline.org/
"Human activities ... are modifying the concentration of atmospheric constituents ... that absorb or scatter radiant energy. ... [M]ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations” (NAS, 2001: p. 21)
"The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue” (NAS, 2001: p. 3)
"Human activities ... are modifying the concentration of atmospheric constituents ... that absorb or scatter radiant energy. ... [M]ost of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations” (NAS, 2001: p. 21)
"The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue” (NAS, 2001: p. 3)
National Academy of Sciences Committee on the Science of Climate Change, 2001: Climate Change Science: An Analysis of Some Key Questions. National Academy Press, Washington, DC.
US National Academy of Sciences
A critical examination of climate modeling as a basis for assessing climate
change
A critical examination of climate modeling as a basis for assessing climate
change Morning session:
The scientific basis underpinning climate change projections for the 21st century
Recent trends in Midwest climate relating to agriculture and farmer adaptations
Afternoon sessions: Limitations of climate models (Arritt) Recent mild summers: What’s going on?
(Anderson) Emerging climate forecasting techniques
(applications maybe you hadn’t thought about)(Gutowski)
Morning session: The scientific basis underpinning climate
change projections for the 21st century Recent trends in Midwest climate relating to
agriculture and farmer adaptations Afternoon sessions:
Limitations of climate models (Arritt) Recent mild summers: What’s going on?
(Anderson) Emerging climate forecasting techniques
(applications maybe you hadn’t thought about)(Gutowski)
Presenters collectively have over 50 years of global and regional climate modeling research experience
In science, the prevailing theory is the one that explains the balance of evidence
What is the evidence?
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
http://data.giss.nasa.gov/gistemp/graphs/
NASA
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
Source: IPCC, 2001: Climate Change 2001: The Scientific Basis
Temperature Trends in Upper and Lower Atmosphere
Temperature Trends in Upper and Lower Atmosphere
Upper Atmosphere
(Stratosphere)
Lower Atmosphere
(Troposphere)
“One of the clearest trends in the United States observational record is an increasing frequency and intensity of heavy precipitation events… Over the last century there was a 50% increase in the frequency of days with precipitation over 101.6 mm (four inches) in the upper midwestern U.S.; this trend is statistically significant “
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Arctic Sea-Ice Decline
Decline in Greenland Ice Mass
Equivalent to about 5 ft of ice over the state of Iowa each year
Emanual, Kerry, 2005: Increasing destructiveness of tropical cyclones over the past 30 years. Nature, 436, 686-688.
Sea-surface temperature
V V
Tropical Atlantic OceanHurricane Power Dissipation Index (PDI)
V
Ocean Heat Content
1oC rise in top 3 m of global ocean is equivalent to a 1oC rise in entire atmosphere
Where is this extra heat coming from?
Possible mechanisms:
• More solar radiation• Less reflection from clouds• Less reflection from Earth’s
surface• More energy trapped and recycled by ozone and greenhouse gases
Earth’s Energy Balance:
Incoming solar = outgoing infrared radiation
But rapid changes in atmosphere and ocean temperatures and loss of land and sea ice indicate an imbalance
Earth’s Energy Balance:
Incoming solar = outgoing infrared radiation
But rapid changes in atmosphere and ocean temperatures and loss of land and sea ice indicate an imbalance
?
?
? ?
*Other solar cycles have periods of 22,000, 41,000, and 100,000 years with 0.1% variation.
0.1%
0.1%
Forcing Factors in the Global Climate
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
More trapped (recycled) heat
More cloud & land reflection
See Arritt for details this afternoon
Increased Greenhouse Increased Greenhouse Gases => Global HeatingGases => Global Heating
Increased Greenhouse Increased Greenhouse Gases => Global HeatingGases => Global Heating
Increasing Increasing greenhouse gases greenhouse gases increases heating increases heating of the Earthof the Earth
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009.
Global Carbon Emissions (Gt)
Actual emissions are exceeding worst case scenarios projected in 1990
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Warming of the Lower and Upper Atmosphere Produced by Natural and Human Causes
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Warming of the Lower and Upper Atmosphere Produced by Natural and Human Causes
Note that greenhouse gases have a unique temperature signature, with strong warming in the upper troposphere, cooling in the lower stratosphere and strong warming over the North Pole. No other warming factors have this signature.
http://www.ncdc.noaa.gov/img/climate/research/2008/ann/global-jan-dec-error-bar-pg.gif
Global Mean Surface Temperature
Attribution studies: See Anderson this afternoon for applications to the Midwest
Source: Jerry Meehl, National Center for Atmospheric Research
The balance of evidence for the magnitude and distribution of warming is explained by increases in atmospheric greenhouse gases
IPCC Fourth Assessment Report Summary for Policy Makers
Balanced fuel sourcesEnergy intensive
More environmentally friendly
If current emission trends continue, global temperature rise will exceed worst case scenarios projected in 2007
FI =fossil intensive
IPCC 2007
December-January-February Temperature Change
A1B Emission Scenario2080-2099 minus1980-1999
7.2oF
6.3oF
IPCC 2007
June-July-August Temperature Change
A1B Emission Scenario2080-2099 minus1980-1999
4.5oF
5.4oF
June-July-August Temperature Change
A1B Emission Scenario2080-2099 minus1980-1999
4.5oF
5.4oF
Not the direction of current trends (see Anderson this afternoon)
IPCC 2007
IPCC 2007
Low confidence in model projection of summer precipitation. See Arritt presentation this afternoon
IPCC 2007
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Low confidence: See Arritt this
afternoon
Emerging techniques for improvement: See Gutowski this
afternoon
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
Trend of increase in occurrence of heavy precipitation over the 20th C is consistent with increasing GHG concentrations.
Frequency of intense precipitation events is likely to increase in the future.
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
MitigationPossible
AdaptationNecessary
AdaptationNecessary
The planet is committed to a warming over the next 50 years regardless of political decisions
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
MitigationPossible
AdaptationNecessary
AdaptationNecessary
The planet is committed to a warming over the next 50 years regardless of political decisions
Farmers install more drainage tile
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
AdaptationNecessary
AdaptationNecessary
MitigationPossible
The planet is committed to a warming over the next 50 years regardless of political decisions
Karl, T. R., J. M. Melillo, and T. C. Peterson, (eds.), 2009: Global Climate Change Impacts in the United States. Cambridge University Press, 2009, 196pp.
AdaptationNecessary
AdaptationNecessary
MitigationPossible
The planet is committed to a warming over the next 50 years regardless of political decisionsFarmers plant earlier,
choose longer season hybrids
Adapted from Folland et al. [2001]
Observed Summer (JJA) Daily Maximum Temperature Changes (K), 1976-2000
Adapted from Folland et al. [2001]
Observed Summer (JJA) Daily Maximum Temperature Changes (K), 1976-2000
See Anderson presentation this afternoon
Des Moines Airport Data
1983: 13
1988: 10
2009: 0
Des Moines Airport Data
1983: 13
1988: 10
2009: 0
6 days ≥ 100oF in the last 20 years
State-Wide Average Data
State-Wide Average Data
Totals above 40”
Cedar Rapids Data
Cedar Rapids Data
Relationship of Streamflow to Precipitation in Current and Future Climates
D. Herzmann, Iowa Environmental Mesonet
State-Wide Average Data
Projected Changes* for the Climate of the Midwest
Temperature
Projected Changes* for the Climate of the Midwest
Temperature
*Estimated from IPCC reports
*Estimated from IPCC reports
Projected Changes* for the Climate of the Midwest
Precipitation
Projected Changes* for the Climate of the Midwest
Precipitation
*Estimated from IPCC and CCSP reports
Projected Changes* for the Climate of the Midwest
Other
Projected Changes* for the Climate of the Midwest
Other
Iowa Agricultural Producers’ Adaptations to Climate Change
Iowa Agricultural Producers’ Adaptations to Climate Change
Longer growing season: plant earlier, plant longer season hybrids, harvest later
Wetter springs: larger machinery enables planting in smaller weather windows
More summer precipitation: higher planting densities for higher yields
Wetter springs and summers: more subsurface drainage tile is being installed, closer spacing, sloped surfaces
Fewer extreme heat events: higher planting densities, fewer pollination failures
Higher humidity: more spraying for pathogens favored by moist conditions
Drier autumns: delay harvest to take advantage of natural dry-down conditions
Longer growing season: plant earlier, plant longer season hybrids, harvest later
Wetter springs: larger machinery enables planting in smaller weather windows
More summer precipitation: higher planting densities for higher yields
Wetter springs and summers: more subsurface drainage tile is being installed, closer spacing, sloped surfaces
Fewer extreme heat events: higher planting densities, fewer pollination failures
Higher humidity: more spraying for pathogens favored by moist conditions
Drier autumns: delay harvest to take advantage of natural dry-down conditions
HIGHER YIELDS!!Is it genetics or climate? See
Anderson this afternoon
Will These Agriculturally Favorable Midwest Climate Trends Continue?Will These Agriculturally Favorable Midwest Climate Trends Continue?
In the short-term (next 5-10 years) climatic conditions will be dominated by natural variability from base conditions of the past 20 years (not long-term averages)
If we continue to have high spring and summer rainfall and soil moisture, we likely will continue to have lower chances of extended periods of extreme heat
If we continue to have high spring and summer rainfall and soil moisture, we likely will continue to have pathogens favored by high humidities
In the longer term (>50 years), hot summers, milder winters, and higher variability of precipitation will become more dominant
Failure to limit global carbon emissions will accelerate trends toward less favorable agricultural climate for Iowa
In the short-term (next 5-10 years) climatic conditions will be dominated by natural variability from base conditions of the past 20 years (not long-term averages)
If we continue to have high spring and summer rainfall and soil moisture, we likely will continue to have lower chances of extended periods of extreme heat
If we continue to have high spring and summer rainfall and soil moisture, we likely will continue to have pathogens favored by high humidities
In the longer term (>50 years), hot summers, milder winters, and higher variability of precipitation will become more dominant
Failure to limit global carbon emissions will accelerate trends toward less favorable agricultural climate for Iowa
Caution: These are my speculations!!
Suitability Index for Rainfed Agriculture
IPCC 2007
SummarySummary There is no scientifically defensible explanation for
atmospheric warming, increase in ocean heat content, and loss of ocean and land ice over the last 40 year other than increase of anthropogenic greenhouse gases
Some recent climate trends in the Midwest that have been favorable to agriculture likely will continue in the next few years
Climate challenges to agriculture will intensify toward mid-century
Global and regional climate models have much to offer for understanding future Midwest and global agricultural production: Agriculture needs future climate information at regional scales.
The afternoon climate model session will be led by world experts in seasonal climate forecast models, future climate extremes, and attribution studies.
There is no scientifically defensible explanation for atmospheric warming, increase in ocean heat content, and loss of ocean and land ice over the last 40 year other than increase of anthropogenic greenhouse gases
Some recent climate trends in the Midwest that have been favorable to agriculture likely will continue in the next few years
Climate challenges to agriculture will intensify toward mid-century
Global and regional climate models have much to offer for understanding future Midwest and global agricultural production: Agriculture needs future climate information at regional scales.
The afternoon climate model session will be led by world experts in seasonal climate forecast models, future climate extremes, and attribution studies.
For More InformationFor More Information National academies of science joint statement (May 2009):
G8+5 Academies’ joint statement: Climate change and the transformation of energy technologies for a low carbon future. [http://www.nationalacademies.org/includes/G8+5energy-
climate09.pdf] North American Regional Climate Change Assessment
Program: http://www.narccap.ucar.edu/
For current activities on the ISU campus, regionally and nationally relating to climate change see the Climate Science Initiative website: http://climate.agron.iastate.edu/
Contact me directly: [email protected]
National academies of science joint statement (May 2009): G8+5 Academies’ joint statement: Climate change and the transformation of energy technologies for a low carbon future. [http://www.nationalacademies.org/includes/G8+5energy-
climate09.pdf] North American Regional Climate Change Assessment
Program: http://www.narccap.ucar.edu/
For current activities on the ISU campus, regionally and nationally relating to climate change see the Climate Science Initiative website: http://climate.agron.iastate.edu/
Contact me directly: [email protected]