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Announcements – Oct 25, 2006
New York Times
October 1, 2004
With Russia's Nod, Treaty on Emissions Clears Last
Hurdle
The long-delayed Kyoto Protocol on global warming overcame
its last critical hurdle to taking effect around the world on
Thursday when Russia's cabinet endorsed the treaty and sent
it to Parliament. The treaty is the first to require cuts in
emissions linked to global warming. The United States has
rejected the treaty and will not be bound by its restrictions.
But the treaty, which has already been ratified by 120
countries will take effect if supporters include nations
accounting for at least 55 percent of all industrialized
countries' 1990-level emissions. The only way for it to cross
that threshold was with ratification by Russia. In 1990, the
United States accounted for 36.1 percent of emissions from
industrialized countries, and Russia 17.4 percent.
CNN
Nov. 10, 2004
Climate report leaves U.S. policy unchanged Climate treaty considered threat to U.S. jobs and
economic growth
WASHINGTON (AP) -- President Bush is holding fast to
his rejection of mandatory curbs on greenhouse gases
that are blamed for global warming, despite a fresh report
from 300 scientists in the United States and seven other
nations that shows Arctic temperatures are rising. Critics
say Bush's opposition is ironic because the treaty was
modeled after the market-based U.S. program for cutting acid
rain created in 1990 by Bush's father and often pointed to by
the current administration as a success story.
CNN
President Bush’s plan offers incentives to businesses to
voluntarily reduce U.S. greenhouse gas emissions by an
estimated 4.5 percent over 10 years and to reduce power plant
emissions. Bush's plan is dramatically lower than the
estimated 33 percent mandatory reduction sought by the Kyoto
agreement for the United States, the world's largest producer
of greenhouse gas emissions.
Bush has criticized the treaty, saying it set unrealistic goals
and could damage the U.S. economy. But other nations worry
about scientific concerns that climate change could lead to
severe floods and droughts, rising sea levels and an increase
in malaria and respiratory disease.
Friday, 8 September 2006,
World's most wanted: climate change
Human-induced climate change must be treated as
an immediate threat to national security and
prosperity, says John Ashton, the UK's climate
change envoy. He argues that we must secure a
stable climate whatever the cost, as failure to do so
will cost far more.
26 September 2006
World 'warmest for 12,000 years
The world is the warmest it has been in the last
12,000 years as a result of rapid warming over the
past 30 years, a study has suggested. Nasa
climatologists said the Earth had warmed by
about 0.2C (0.4F) in each of the last three
decades.
As a result, plant and animal species were
struggling to migrate fast enough to cooler
regions, they said.
Air Quality II
Lecture Objectives:
1.
What is the greenhouse effect?
2.
Is global climate change/warming
real?
3.
What are the worst-case scenarios
under global climate change?
The Issue
Greenhouse Gases



Gases that are transparent to light, but absorb infrared radiation
Mainly CO2, but also chlorofluorocarbons, methane, nitrous
oxide
General Causes

Burning coal, oil, gas: releases CO2

Deforestation: releases stored CO2, reduces capacity for
CO2 storage

More CO2 emitted than can be absorbed

Industrialized nations
The Controversy

Debate: Are the increasing levels of CO2 due to
natural climate cycles or human-generated?

Opponents argue that reducing emissions will hurt
the economy

Supporters argue that not reducing emission may
have catastrophic effects, so isn’t it better to be safe
than sorry?
What do we know for sure?

Human activities are changing the
composition of Earth's atmosphere.

Human activities are strengthening Earth's
natural greenhouse effect.

A warming trend of about 1°F has been
recorded since the late 19th century.
http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html
What is likely but not certain?

Rising levels of greenhouse gases in the
atmosphere will increase global warming


to what extent is difficult to determine.
Average global temperatures will continue to
rise. By how much and how fast remain
uncertain

Could be 2.2 - 10°F
http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html
What are the big unknowns?

Exact local impacts on health, agriculture,
water resources, forests, wildlife and coastal
areas

Large-scale predictions easier to make than
small-scale predictions



Will local rainfall increase or decrease?
Will hurricanes be more frequent or severe?
Will ocean currents change?
http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html
Evidence for Global Climate Change

IPCC –Intergovernmental Panel on Climate Change

Appointed by the United Nations in 1988

Mission: To study the issue and make recommendations

First Assessment published 1990

Second Assessment published in 1996

Third Assessment published in 2001

http://www.ipcc.ch/

Scientific Basis, Impacts Adaptation and Vulnerability, Mitigation,
Synthesis
Evidence for GCC

IPCC conclusions

CO2 and temperature correlated

0.6C average temperature increase since 1861

Declines in snow and ice cover since 1960s

10-20 cm sea-level increase in last 100 years

human activity is the cause

Near unanimity of scientific opinion

National Research Council (U.S.) agrees
CO2 and temperature are correlated
Climatic
records
indicate a
correlation
between CO2
concentration
and global
temperatures
over the past
400,000 years
Nature 2002 419:188-190
0.6C average
temperature
increase since
1861
Declines in snow
and ice cover
Mount Kilimanjaro, one of the
few places in the world where
ice and snow can be found on
the equator, could lose its
entire ice field by 2020 because
of climate change.
The ice fields Ernest
Hemingway once described as
"wide as all the world, great,
high, and unbelievably white in
the sun" have lost 82 percent of
their ice since 1912—the year
their full extent was first
measured.
Increases in sea level (10-20 cm)
http://www.umac.org/ocp/paradise/outlook.htm
Human activity is the cause
www.ipcc.ch
Effects of Global Warming
Effects of Global Warming

Not uniform; regional differences


some areas hotter, some colder, some wetter, some
dryer!!!
These local, regional changes are difficult to
predict
Rising sea levels
coastal flooding
Worsening Health Effects

Direct heat stress: 2003 heat wave in France
killed 15,000

Diseases: cold weather kills many diseases,
especially mosquito-borne diseases:

malaria, dengue fever, yellow fever, encephalitis

Ozone: pollutant near the ground

Cholera – ENSO link
Forests and Natural Areas
Shift northward in
species distribution
Agriculture and Food Supply

Increase yields for some crops, but not
uniformly

World food supply unaltered, but problems in
poor countries will likely get worse

Increase pest populations

Increase irrigation
Disruption of Water & Weather Cycles

Major changes to hydrological cycle
 Increased evaporation will dry some areas





Exacerbate problems in Middle East & Africa
Decreased hydropower
Impair navigation ability
Decrease water quality & recreation
Increased precipitation will flood some
areas


Increased intensity of storms
Problems with flood control
Cascading effects: extreme cooling
Worst-case scenario…
Increase in freshwater input to North Atlantic
could halt warmer currents & thus cool Gulf
Stream
 Drastic, rapid climate changes in W. Europe
(also NE United States, E. Canada)



Southern England like Iceland
4-year study on currents started Feb 2004
(Nature 427:769)
Is there anything we can do?
Reduce Greenhouse Gases by:
1) Reducing emissions
2) Increasing CO2 uptake



Political and economic issues
Annual US per capita contribution = 22 tons of CO2
emissions per year
World average per capita = 6 tons
How to reduce greenhouse gases?

Improve energy efficiency


Current & future buildings using available, cost-effective
technologies
Increase investments in renewable and longer-term
technologies.

Carbon tax: stimulate development of increased
efficiency

Removal of CO2 from atmosphere



plant trees
Stop deforestation
Increase CO2 storage in the ocean
Side Benefits of reducing emissions
1)
2)
3)
Reduced air pollution
Reduced human death, disease = lower
health care costs & increased productivity
Improved energy efficiency
o
o
4)
Reduced dependence on fossil fuels, foreign oil
Reduced need for expensive new power plants
Increased investment in alternative energy
technologies
Who reaps benefits and who pays costs?
VP Cheney: “Conservation may be a sign of personal
virtue, but it is not a sufficient basis for a sound,
comprehensive energy policy.”
Pres. Bush: “As you know, I oppose the Kyoto Protocol
because it exempts 80 percent of the world… and would
cause serious harm to the U.S. economy”
Who reaps benefits and who pays costs?
Points to know – April 21
What is the greenhouse effect? What are the greenhouse
gases?
2. What do we know for sure in the controversy over global
climate change? What are the big unknowns?
3. What is the IPCC? What conclusions did it reach
regarding global warming? Did the National Research
Council of the U.S. agree with their findings?
4. Will global warming be felt evenly across the earth? Can
we predict what will happen in a given region?
5. What will happen to the hydrological cycle? What is a
worst-case scenario of global warming?
6. How can we reduce greenhouse gases? What are some
side benefits of emission reduction?
1.