project to intercompare regional climate simulations carbon dioxide and climate change eugene s....

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

[email protected]

Lecture to Political Science Class onScience, Technology and Public Policy

Iowa State University7 February 2004


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


2004


2004

2040


Stabilization at 550 ppm


“Business as Usual”(fossil intensive)

2100


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

40% Probability

5% Probability


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

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


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


Election 2004Issues and Their Time Scales

What are the election issues in 2004, and how long will decisions on these issues have an

impact?


2004 Issues

Jobs US Economy National security, terrorism War Environment


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


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


2004 Issues: National Security

Nazi Germany: 10 years (impact 50 years) China ?? Rawanda ??

-> Time scale of terrorism: 5-50 years


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


2004 Issues: Environment(Global Warming)

Time scale of environmental decisionson global warming:

200 - 2,000 years !!


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


For More Information

See my online Global Change course:

http://www.meteor.iastate.edu/gccourse

Contact me directly:

[email protected]

project to intercompare regional climate simulations carbon dioxide and climate change eugene s....

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