agriculture and climate change
DESCRIPTION
Agriculture and Climate Change. Eugene S. Takle Agronomy Department Geological and Atmospheric Science Department Iowa State University Ames, Iowa 50011 [email protected]. Underwriting/Marketing Seminar, 30 March 2005. Outline. Evidence for global climate change - PowerPoint PPT PresentationTRANSCRIPT
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Agriculture and Climate Change
Eugene S. TakleAgronomy Department
Geological and Atmospheric Science Department
Iowa State University
Ames, Iowa 50011
Underwriting/Marketing Seminar, 30 March 2005
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Outline Evidence for global climate change Future atmospheric carbon dioxide concentrations Simulations of global climate and future climate
change Impacts of climate change for the US Midwest “Climate surprises” Social inequities and ethical issues
surrounding climate change Summary
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Associated Climate Changes
Global sea-level has increased 1-2 mm/yr Duration of ice cover of rivers and lakes decreased by 2 weeks in N.
Hemisphere Arctic ice has thinned substantially, decreased in extent by 10-15% Reduced permafrost in polar, sub-polar, mountainous regions Growing season lengthened by 1-4 days in N. Hemisphere Retreat of continental glaciers on all continents Poleward shift of animal and plant ranges Snow cover decreased by 10% Earlier flowering dates Coral reef bleaching
Source: Intergovernmental Panel on Climate Change, 2001 Report
Source: National Center for Atmospheric Research
The planet is committed toa warming over the next 50 years regardless of political decisions
IPCC Summary for Policy Makers
An increasing body of observations gives a collective picture of a warming world and other changes in the climate system
IPCC Summary for Policy Makers
An increasing body of observations gives a collective picture of a warming world and other changes in the climate system
Emissions of greenhouse gases and aerosols due to human activities continue to alter the atmosphere in ways that are expected to affect the climate
IPCC Summary for Policy Makers, cont’d
Confidence in the ability of models to project future climate has increased
IPCC Summary for Policy Makers, cont’d
Confidence in the ability of models to project future climate has increased
There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities
IPCC Summary for Policy Makers, cont’d
Anthropogenic climate change will persist for many centuries
Further action is required to address remaining gaps in information and understanding
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Climate Surprises:Low Probability but High-Impact Events
Breakdown of the ocean thermohaline circulation (Greenland melt water)
Breakoff of the West Antarctic Ice Sheet
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Meltwater flows into a large moulin on Greenland and down to the bedrock to "lubricate" the sheet
BBC News: World Editionhttp://news.bbc.co.uk/2/hi/science/nature/2558319.stm
For the Midwest Warming will be greater for winter than summer Warming will be greater at night than during the
day A 3oF rise in summer daytime temperature triples
the probability of a heat wave Growing season will be longer (8-9 days longer
now than in 1950) More precipitation Likely more soil moisture in summer More rain will come in intense rainfall events Higher stream flow, more flooding
Sub-Basins of theSub-Basins of theUpper MississippiUpper MississippiRiver BasinRiver Basin
119 sub-basins
Outflow measuredat Grafton, IL
Approximately oneobserving stationper sub-basin
Approximately onemodel grid pointper sub-basin
RegCM2 Simulation DomainRegCM2 Simulation Domain
Red = global model grid point Green/blue = regional model grid points
Ten-Year Mean Monthly Stream Flow Generated by the Ten-Year Mean Monthly Stream Flow Generated by the RegCM2 Regional Climate Model Driven RegCM2 Regional Climate Model Driven
with HadCM2 Global Model Results for the with HadCM2 Global Model Results for the Contemporary and Future Scenario (2040s) ClimateContemporary and Future Scenario (2040s) Climate
Relation of Runoff to Precipitation Relation of Runoff to Precipitation for Various Climatesfor Various Climates
More precip goes to streamflow in a future climate
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Social Inequities due to Climate Change
Agricultural production Freshwater availability Sea-water innundation Intergenerational equities
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Social Inequities due to Climate Change
Agricultural production Freshwater availability Sea-water innundation Intergenerational equities
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Impact on US Agriculture(my speculations)
The US is a large enough country at a high enough latitude that it will have regional winners and losers
Areas now marginal for agriculture may become less suitable Some areas now having abundant water but limited growing seasons may be
winners Areas with good soils and robust climate, like Iowa, may be impacted less The US Midwest may experience more variability from
year to year, which would make agricultural yields more variable (flooding, water-logging, drought)
Changes in consumption and agricultural production in other nations may affect US agriculture more than changes to US climate
Environmental refugees?
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Social Inequities due to Climate Change
Agricultural production Freshwater availability Sea-water innundation Intergenerational equities
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Social Inequities due to Climate Change
Agricultural production Freshwater availability Sea-water innundation Intergenerational equities
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Sea-Water InnundationExample: The Maldives
Area: 115 square miles Population: 143,000 Highest point: 20 ft above sea level
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Social Inequities due to Climate Change
Agricultural production Freshwater availability Sea-water innundation Intergenerational inequities
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Intergenerational Inequities
Sustainable Development: “To meet the needs of the present without compromising the ability of future generations to meet their needs.”
Energy sources? Non-renewable earth resources? Agricultural productivity? Fresh water supplies? Heavy metal contamination of soil
and water?
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Summary
Climate change is real and we need to be doing something about it
The longer we wait, the fewer our options Regional patterns of warming will be complicated Climate surprises can’t be discounted Climate change will create regional
agricultural winners and losers Climate change carries ethical
implications
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
For More Information
See my online Global Change course:
http://www.meteor.iastate.edu/gccourse
Contact me directly:
http://www.meteor.iastate.edu/faculty/takle/