PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Carbon Dioxide and Climate Change
Eugene S. TakleAgronomy Department
Geological and Atmospheric Science Department
Iowa State University
Ames, Iowa 50011
Lecture to Political Science Class onScience, Technology and Public Policy
Iowa State University7 February 2004
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 Implications for stream flow Impact of 2004 election decisions Summary
Carbon Dioxide and Temperature
Carbon Dioxide and Temperature
2004
Carbon Dioxide and Temperature
2004
2040
Carbon Dioxide and Temperature
Stabilization at 550 ppm
Carbon Dioxide and Temperature
“Business as Usual”(fossil intensive)
2100
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
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
Mann, M. E., R. S. Bailey, and M. K. Hughes, 1999: Geophysical Research Letters 26, 759.
Source: Jerry Meehl, National Center for Atmospheric Research
Source: National Center for Atmospheric Research
Source: Intergovernmental Panel on Climate Change, 2001 Report
40% Probability
5% Probability
Source: Intergovernmental Panel on Climate Change, 2001 Report
Climate Change Projected for 2100
Rapid Economic Growth
Slower Economic Growth
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
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
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
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
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
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Soil Water Assessment Tool (SWAT)
Long-term, continuous watershed simulation model (Arnold et al,1998)
Assesses impacts of climate and management on yields of water, sediment, and agricultural chemicals
Physically based, including hydrology, soil temperature, plant growth, nutrients,
pesticides and land management Daily time steps
SWAT Output with Various Sources SWAT Output with Various Sources of Climate Inputof Climate Input
Calibration of SWAT:Calibration of SWAT:Annual Stream Flow at Grafton, ILAnnual Stream Flow at Grafton, IL
Calibration of SWAT:Calibration of SWAT:Monthly Stream Flow at Grafton, ILMonthly Stream Flow at Grafton, IL
Validation of SWAT:Validation of SWAT:Annual Stream Flow at Grafton, ILAnnual Stream Flow at Grafton, IL
Validation of SWAT:Validation of SWAT:Monthly Stream Flow at Grafton, ILMonthly Stream Flow at Grafton, IL
Ten-Year Mean Precipitation Generated by the RegCM2 Ten-Year Mean Precipitation Generated by the RegCM2 Regional Climate Model Driven with HadCM2 Regional Climate Model Driven with HadCM2
Global Model Results for the Contemporary and Global Model Results for the Contemporary and
Future Scenario (2040s) ClimateFuture Scenario (2040s) Climate
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
Comparison of Simulated Stream Flow under Comparison of Simulated Stream Flow under Climate Change with Various Model BiasesClimate Change with Various Model Biases
Relation of Runoff to Precipitation Relation of Runoff to Precipitation for Various Climatesfor Various Climates
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
Election 2004Issues and Their Time Scales
What are the election issues in 2004, and how long will decisions on these issues have an
impact?
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues
Jobs US Economy National security, terrorism War Environment
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues: Jobs
The average American changes jobs about every ? 7 years?
Tenured position at a university ~ 35 years
-> Time scale of jobs 7-35 years
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues: US Economy
Economic cycles last about 5 years Home mortgage lasts about 20 years Factory is productive ~50 years
-> Time scale of economic decisions: 5-50 years
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues: National Security
Nazi Germany: 10 years (impact 50 years) China ?? Rawanda ??
-> Time scale of terrorism: 5-50 years
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues: War
Wars last 2-5 years Impact of WWII ~50-100 years
-> Time scale of war 2-100 years
Decisions we make nowDetermine global warmingFor the next 200-2,000years
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues: Environment(Global Warming)
Time scale of environmental decisionson global warming:
200 - 2,000 years !!
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
2004 Issues
Jobs: 7-35 years US Economy: 5-50 years National security, terrorism: 5-50 years War: 2-100 years Environment: 200-2,000 years
PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS
For More Information
See my online Global Change course:
http://www.meteor.iastate.edu/gccourse
Contact me directly: