Global Warming: Is it Real? Can it Affect Violent Weather? (David Karoly, Ph.D.)

8/7/2019 Global Warming: Is it Real? Can it Affect Violent Weather? (David Karoly, Ph.D.)

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Global Warming:Global Warming:

Is it real?Is it real?

Can it affect violent weather?Can it affect violent weather?

Global Warming:Global Warming:

Is it real?Is it real?

Can it affect violent weather?Can it affect violent weather?

Based on

Climate Change 2001: The Scientific Basis

Third Assessment Report of IPCCSummary for Policy Makers

available from www.ipcc.ch

and recent updates


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Recent global warming quotes Senator James Inhofe (R, Oklahoma), Chair,

Senate Environment and Public Works Comm., in

a speech to the US Senate on Jan 4, 2005 I

called the threat of catastrophic global warming the

greatest hoax ever perpetrated on the American

people

British Prime Minister Tony Blair in a speech on 14

Sept 2004 I want to concentrate on what I believe

to be the world's greatest environmental challenge:climate change


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The global-average surface temperature has

increased over the 20th century by 0.60.2CThe 4 hottest years globally were 1998, 2002, 2003 and 2004.

From the Hadley Centre, UK


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Reconstructions of climate data for the last 1000years ... indicate this warming was unusual and is

unlikely to be entirely natural in origin


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Concentrations

of atmospheric

greenhouse gases

have continued

to increase as aresult of human

activities


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Most of the observed warming over the last 50 years is

likely to have been due to the increase in greenhouse gas

concentrations

Runs

with

NCARclimate

model


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In the light of new evidence andtaking into account the remaining

uncertainties, most of the observed

warming over the last 50 years islikely to have been due to the

increase in greenhouse gas

concentrations


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Human influences will continue to

change atmospheric composition

throughout the 21st century

Emission Scenarios of the IPCCA1: rapid growth, rapid technologyintroduction

A2:self-reliance and local identity

B1: clean and resource efficient technology

B2: local, environmental, social equity diversetechnology


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Global average temperature and sea level are

projected to rise under all IPCC SRES scenarios.


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The projected

rate of warming

is much largerthan the

observed

changes during

the 20thcentury and is

very likely to be

without

precedent

during at leastthe last 10,000

years


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Can it affect violent weather?

Poleward shift of climate zones

Warmer temperatures mean higher moisture

content in the atmosphere more intense rainfall,

more flash floods

More evaporation in summer - less soil moisture,more droughts

Hurricanes: warmer ocean temperatures likely to

lead to more intense storms, frequency change??

Severe storms, tornados: very uncertain

Sea level rise: will cause greater impacts

from coastal storms


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Documents

Global Warming: Is it Real? Can it Affect Violent Weather? (David Karoly, Ph.D.)