project to intercompare regional climate simulations global change and antarctica eugene s. takle...

PROJECT TO INTERCOMPARE REGIONAL CLIMATE SIMULATIONS

Global Change and Antarctica

Eugene S. TakleAgronomy Department

Geological and Atmospheric Science Department

Iowa State University

Ames, Iowa 50011

[email protected]

ISU Biology Travel Class, 22 September 2004


Outline

Evidence for global climate change Future atmospheric carbon dioxide

concentrations Simulations of global climate and future

climate change Role of Antartica in climate change 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.

Hansen, Scientific American, March 2004

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

There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities

Anthropogenic climate change will persist for many centuries


Climate Surprises

Breakdown of the ocean thermohaline circulation (Greenland melt water)

Breakoff of the West Antarctic Ice Sheet

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

“Warming Hole”

TTmaxmax (JJA) (JJA)˚C


Global warming is at least as important an issue as gay marriage or the rising cost of Social Security.

And if it is not seriously debated in the general election, it will measure the irresponsibility of the entire political class. This is an issue that cannot, and must not, be ignored any longer.


Global warming is at least as important an issue as gay marriage or the rising cost of Social Security.

And if it is not seriously debated in the general election, it will measure the irresponsibility of the entire political class. This is an issue that cannot, and must not, be ignored any longer.Walter Cronkite12 March 2004

http://www.philly.com/mld/dailytimes/news/opinion/8159334.htm


What Can I Do? Conserve energy Adopt a simpler lifestyle:

– “Elegant simplicity”– “Sophisticated modesty”– “Affluence lite”

Sustainable Development:

To meet the needs of the present without compromising the ability of future generations to meet their needs Brundtland Commission (World Commission on Environment and Development)

Calving of an Iceberg

9 Jan 1995 12 Feb 1995The ice shelf which formerly occupied Prince Gustav Channel and connected James Ross Island to the Antarctic Peninsula Disintegrated making James Ross Island circumnavigable for the first time in recorded history. The new iceberg calved from the Larsen Ice Shelf and measured 78 km x 37 km x 200 m thick.


Summary Climate change is real and should be considered something

other than “tomorrow’s problem” We are committed to a warming over the next 40 years

regardless of what policy path we choose Policy decisions today will affect global warming and

associated environmental changes in the latter half of the 21st century and beyond

Consider adopting a simpler lifestyle Ice is very important to the climate

system and needs to be protected


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 global change and antarctica eugene s. takle...

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