© 2011 Pearson Education, Inc. CHAPTER 18 Global Climate Change.

© 2011 Pearson Education, Inc.

CHAPTER 18

Global Climate Change


An introduction to global climate change• On August 29, 2005, Hurricane Katrina landed east of

New Orleans• The costliest ($134 billion in damage) storm ever• The deadliest storm (killing 1,800) since 1928• Leaving mountains of debris, ruined homes and lives

• A month later, Hurricane Rita hit Louisiana and Texas• 2005 had a record 27 named storms• 2007 had 15 and 2008 had 18 named storms

• There is a link between hurricanes and global warming• Warmer oceans create humid air, leading to hurricanes


Number of category 4 and 5 hurricanes


The atmosphere

• Atmosphere: a collection of gases held by gravity around the Earth

• Troposphere: the lowest level• Gases moderate the flow of energy to Earth• Gases are involved with biogeochemical cycling of

elements• Ranges from 5 to 10 miles thick• Contains almost all the water vapor and clouds• Gets colder with altitude• Mixed air allows pollutants to reach the top of the

layer


Other atmospheric layers

• Tropopause: caps the troposphere• Air shifts from cooling with height and begins to warm

• Stratosphere: temperature increases with altitude• To 40 miles above Earth’s surface

• Ozone (O3) absorbs the Sun’s high-energy radiation

• Due to little mixing and no precipitation, substances remain for long periods of time

• Mesosphere and thermosphere: declining ozone levels• Only small amounts of oxygen and nitrogen


Structure and temperature of the atmosphere


Weather

• Weather: day-to-day variations in temperature, air pressure, wind, humidity, precipitation

• Climate: the result of long-term regional weather patterns• Meteorology: the study of the atmosphere (weather and

climate)

• The atmosphere-ocean-land system is a huge weather engine• Driven by the Sun and affected by Earth’s rotation and tilt• Solar energy is reflected (29%) or absorbed by Earth• Absorbed energy heats the ocean, land, and atmosphere• Evaporation, convection, and reradiation of infrared energy

release energy


Solar-energy balance


Flowing air

• Some energy released from Earth goes to the atmosphere• Warmer air expands and rises, creating vertical air

currents• Convection currents: large-scale vertical air

movement

• Horizontal air currents (wind) result from sinking cool air replacing rising warm air• Hadley cell: combination of rising warm air and

sinking cool air• Creates regions of high rainfall (equator), deserts, and

trade winds (horizontal winds)


Convection• Convection currents: bring day-to-day weather

changes• They move from west to east

• Solar-heated rising air creates atmospheric high pressure• Leaving behind lower pressure closer to Earth

• Moist high-pressure air cools (through reradiation and condensation)• Flowing horizontally to sinking cool, dry air regions of

lower pressure• The air is warmed and creates a region of higher

pressure• Differences in air pressure lead to airflows (winds)


A convection cell


Jet streams

• Larger-scale air movements of Hadley cells are influenced by Earth’s rotation from west to east• Creating trade winds over oceans and the west-to-

east flow of weather

• Jet streams: rivers of air created higher in the troposphere from Earth’s rotation and air-pressure gradients• Move faster than 300 mph• Meander considerably• Can steer major air masses in the lower troposphere


Put together …

• Fronts: boundaries where air masses of different temperatures and pressures meet• Regions of rapid weather change• Other movements of air masses due to different

pressures and temperatures: hurricanes, typhoons, tornadoes

• Monsoons: major seasonal airflows • A reversal of previous wind patterns• Created by major differences in cooling and heating

between oceans and continents• India’s summer monsoons bring rains and floods


Climate is …

• Climate: the general patterns of weather that characterize different regions of the world

• Climate results from all the combined elements of• General atmospheric circulation patterns and

precipitation• Wind and weather systems • Rotation and tilt of Earth, which creates seasons


Climate change science

• Biomes: reflect plant, animal, and microbe adaptations to the prevailing weather patterns (climate) of a region• Humans can adjust to almost any climate• But other organisms can’t

• A major change in the climate represents a serious threat to the structure and function of existing ecosystems

• Because humans depend on ecosystems for vital goods and services, we need functioning ecosystems


Synopsis of global climate change

• In 2007, scientists from the Intergovernmental Panel on Climate Change (IPCC) sifted through thousands of studies and published the Fourth Assessment Report (AR4)

• The report concluded that warming of the climate is unequivocal• The atmosphere and oceans are warmer• Sea levels are rising and glaciers are melting• There are more extreme weather events


Annual mean global surface temperature anomalies


The IPCC’s report

• The report concluded that it is very likely (90% probability) that warming is caused by human factors• Increased greenhouse gases (GHGs) trap infrared

radiation

• GHGs come from burning fossil fuels• Along with deforestation

• The major GHG: CO2

• Responses to climate change• Mitigation: reducing GHG emissions • Adaptation: adjusting to climate change


Atmospheric carbon dioxide concentrations


IPCC• Founded in 1988 by the UN Environmental Program and

the World Meteorological Society to provide accurate and relevant information leading to understanding human-induced climate change

• Working Group I: assesses scientific issues of climate change

• Working Group II: evaluates impacts and adaptation to it• Working Group III: investigates ways to mitigate its

effects• The AR4 report had over 2,000 experts from 154

countries• Risk assessment: is the climate changing?• Risk management: how do we adapt and mitigate

effects?


Third assessment

• The IPCC’s 2001 report showed• Increasing information shows a warming world• Humans are changing the atmosphere, which will

affect climate• We have increased confidence in models of future

climate change• Stronger evidence that most recent warming is

human-caused• Human influences will continue to change the

atmosphere• Temperature and sea levels are rising• We need more information and understanding


A Nobel Effort

• AR4 produced Climate Change 2007: Synthesis Report• Contained key findings of the working groups

• The 2007 Nobel Peace Prize went to the IPCC and former Vice President Al Gore: the leading advocate of the need to take action on climate change• For their efforts to disseminate knowledge about man-

made climate change and to lay groundwork to counter it

• Gore also was awarded the Academy Award for his film An Inconvenient Truth


Climates in the past

• It is harder to find evidence of climate change the further into the past we search

• Records of temperature, precipitation, storms have been kept for only 100 years• Since 1880, especially since 1976, our climate

warmed

• Proxies: records providing information on climate• Using temperature, ice cover, precipitation, tree rings,

pollen, landscapes, marine sediments, corals, etc.• Earth warmed from 1100 to 1300 A.D.• Little Ice Age: 1400–1850


Ice cores

• Analyzing ice cores from Greenland and the Antarctic shows global climate can change within decades• Uses CO2 and CH4 (methane) and isotopes of O and H

• Climate oscillates between ice ages and warm periods• Ice ages tie up water in glaciers, lowering sea levels• 8 glacial periods occurred over the past 800,000 years

• Ice ages have lower GHGs and temperatures• CO2 levels ranged between 150 and 280 ppm

• Milanovitch cycles: climate oscillations due to Earth’s orbit• Periodic intervals of 100,000, 41,000, and 23,000 years


Past climates, as determined from ice cores


Rapid changes

• Rapid climatic fluctuations are superimposed on the major oscillations during glaciation and warmer times

• The Younger Dryas event: 11,700 years ago • Dryas: a genus of arctic flower• Arctic temperatures rose 7ºC in 50 years• Caused enormous impact on living systems• Warming was not caused by changing solar output


Climate fluctuations


Oceans and climate

• Oceans play a dominant role in determining climate• They are a major source of water and heat

• Evaporation: supplies water vapor to the atmosphere• Condensation: supplies heat to the atmosphere• Heat capacity: oceans absorb energy with heated

water• Oceans convey heat through currents• Thermohaline circulation pattern: the effects of

temperature and salinity on the density of seawater• This giant, complex conveyor belt moves water from

the surface to deep oceans and back


Thermohaline circulation

• High-latitude North Atlantic ocean flows from the Gulf Stream north on the surface and is cooled by Arctic air

• North Atlantic Deep Water (NADW): the cool water increases in density, so it sinks (up to 4,000 m)• The current spreads to Africa’s southern tip• It is joined by cold Antarctic waters• The two streams spread north into the Indian and

Pacific Oceans as deep currents

• The currents slow and warm and rise to the surface• Move back to the North Atlantic


The oceanic conveyor system


Thermohaline circulation affects climate• The movement of warm water toward the North

Atlantic transfers enormous amounts of heat toward Europe, providing a much warmer than expected climate• The circulation pattern cycles over 1,000 years• It is vital to maintaining current climate conditions

• In the past, the conveyor system has been interrupted• Abruptly changing the climate

• Large amounts of fresh water lower water’s density• Preventing the sinking of surface waters• Slowing the northern movement of warmer, saltier

water


Heinrich events

• Heinrich events: fresh water from melting icebergs from the polar ice cap dilutes salt water• Six times in the past 75,000 years • Diluted water doesn’t sink• The conveyor system is shifted southward to

Bermuda (instead of Greenland)• The climate cools in a few decades

• Return of the normal pattern abruptly warms the climate• The Younger Dryas event involved dammed-up water

from glacial Lake Agassiz entering the St. Lawrence


What if …?

• Extended global warming will • Increase precipitation over the North Atlantic• Melt sea ice and ice caps

• The conveyor will decrease over the 21st century• The Achilles’ heel of our climate system: weakening

of the conveyor and a changed climate• Especially in the northern latitudes


Ocean-atmosphere oscillations• These processes produce globally erratic climates• The North Atlantic Oscillation (NAO): atmospheric

pressure centers switch back and forth across the Atlantic• Switching wind and storms

• El Niño/La Niña Southern Oscillation (ENSO): shifts in atmospheric pressure over central equatorial Pacific Ocean• Dominates global climate for over a year at a time• 1997–2000 ENSO cost $36 billion and killed

thousands• Interdecadal Pacific Oscillation (IPO): a warm-cool

cycle that swings over the Pacific over several decades


More ocean-atmosphere oscillations

• Understanding these processes helps clarify some puzzling developments• A global warming trend was stopped in the mid-1940s• But resumed 30 years later• This mid-century cooling resulted from shifting ocean

circulation linked to the NAO

• Ocean-atmosphere oscillations can offset global warming• But greenhouse warming will overcome them and

intensify by the end of this decade


The Earth as a greenhouse

• Factors that influence climate• Internal components: oceans, atmosphere, snow, ice• External factors: solar radiation, Earth’s rotation and

orbit, gaseous makeup of the atmosphere

• Radiative forcing: the influence of any factor on the energy balance of the atmosphere-ocean-land system• Positive (negative) forcing: leads to warming (cooling)

• Forcing is measured in Watts/m2 • Solar radiation entering the atmosphere = 340 W/m2

• Radiation is acted on by forcing factors


Warming processes

• Greenhouse gases (GHGs): water vapor, CO2, other gases

• Light energy goes through the atmosphere to Earth• Earth absorbs and converts energy to heat• Infrared heat energy radiates back to space

• GHGs (but not N2 and O2) in the troposphere absorb some infrared radiation• Direct it back to Earth’s surface

• The greenhouse effect was first recognized in 1827• It is now firmly established


GHGs insulate Earth

• GHGs delay the loss of infrared heat (energy)• Without insulation, Earth would be -19°C instead of

+14°C• Life would be impossible

• Earth’s global climate depends on the concentration of GHGs• Changing amounts of GHGs change positive forcing

agents, which would change the climate

• Tropospheric ozone has a positive forcing effect• Varying with time and location


The greenhouse effect


Cooling processes

• Planetary albedo: sunlight reflected by clouds• Contributes to overall cooling by preventing warming• Low-flying clouds have a negative forcing effect

• High-flying, wispy clouds have a positive forcing effect• Absorb solar radiation and emit infrared radiation

• Snow and ice contribute to albedo by reflecting sunlight • Black carbon soot darkens snow and ice

• Dark snow/ice absorbs radiant energy instead of reflecting it • Reduces albedo


Volcanoes and aerosols• Volcanic activity can lead to planetary cooling• Reflects radiation from particles and aerosols

• Aerosols: microscopic liquid or solid particles from land or water• Industrial aerosols (pollution) cancel some GHG

warming• Sulfates, nitrates, dust, soot from industry and forest

fires• Sooty aerosols (from fires): warming effect• Sulfate aerosols create cooling through more clouds

• Reduced pollution in the U.S. and Europe decreased aerosols• China’s and India’s pollution has increased aerosols


Global warming and cooling


Solar variability• Variation in the Sun’s radiation influences the

climate• Changes in solar radiation occur on 11-year cycles• Solar radiation increases during high sunspot activity

• Sunspots block cosmic ray intensity • Reduce cloud cover and increase solar radiation

• Solar output declined in 1985 and continued for 20 years• But global temperatures rose rapidly

• The IPCC AR4 concluded that GHGs were 13 times more responsible for warming temperatures than solar changes


Thus …

• Global atmospheric temperatures are a balance between positive and negative forcing from natural causes (volcanoes, clouds, natural GHGs, solar irradiance) and forcing from anthropogenic causes (sulfate aerosols, soot, ozone, increased GHGs)

• Forcing agents result in climate fluctuations• It is hard to say any one event or extreme season is

due to humans• But climate has shifted enough to generate

international attention


Evidence of climate change

• Weather varies naturally year to year• Local temperatures may not follow global averages

• But the 10 warmest years on record were 1997–2008• 2005 set a record high—the warmest since the late

1800s• The average global temperature has risen 0.6°C since

the mid-1970s (0.2°C/decade)

• Warming is happening everywhere• Most rapidly at high latitudes of the Northern

Hemisphere

• The warming is a consequence of an “enhanced greenhouse effect”


Satellites

• Measurements of tropospheric temperatures by 13 satellites over 20 years did not show temperature increases• Skeptics made much of this discrepancy

• The Climate Change Science Program (CCSP) • Created in 2002 to address unresolved questions

about climate change• Its 2006 report stated that errors caused the

discrepancy• Corrected and new data agree that surface and

tropospheric temperatures are rising


Ocean warming• Recently, the upper 3,000 meters of the ocean have

warmed• Dwarfing warming of the atmosphere• 90% of the heat increase of Earth’s systems

• Over the last decade, oceans have absorbed most of the non-atmospheric heat

• A long-term consequence: the impact of this stored heat as it comes into equilibrium with the atmosphere• It will increase atmospheric and land heat even more

• A short-term consequence: unprecedented rising sea levels• Thermal expansion and melting glaciers and ice caps


Heat capture by the oceans


The rise in global mean sea level


Other observed changes by the IPCC AR4• Changes are consistent with GHG-caused climate

change• Increased warm temperature extremes• Decreased cold temperature extremes• Spring comes earlier, fall later, in the Northern

Hemisphere• Ecosystems are out of sync• Tree deaths and insect damage• Heat waves are increasing in intensity and frequency• Droughts are increasing in intensity and frequency• 60% of the U.S. is in a drought that started in the

1990s


More changes reported by the IPCC

• Rising Arctic temperatures have caused major shrinkage of Arctic sea ice (11.7% in 10 years)

• Alaska, Siberia, Canada have warmed 5°F in summer, 10°F in winter

• Spring comes 2 weeks earlier than 10 years ago• The polar ice cap has lost 20% of its volume in 20

years• Permafrost is melting• Unprecedented melting of the Greenland Ice Sheet

can raise ocean levels 23 feet


Decline of Arctic sea ice


Other changes reported by the IPCC

• Antarctica temperatures have risen 0.5°–0.85°C• The West Antarctic Ice Sheet (WAIS) is shrinking and

can raise sea levels by 16–20 feet

• Accelerating glacier melting since 1990• Changing patterns of precipitation and flooding• Greater amounts from 30° N and S poleward

• More intense and frequent tropical hurricanes• Marine fish populations have shifted northward

• Ocean acidification: decreased pH due to CO2 absorption• The surface ocean’s chemistry is actually changing


Shrinkage of the Muir glacier


Rising greenhouse gases

• The IPCC AR4 report states that global GHG emissions from humans have grown 70% between 1970 and 2004• The most important GHG is carbon dioxide (CO2)

• Carbon dioxide:• Over 100 years ago, Swedish scientist Arrhenius

suggested that burning fossil fuels may increase CO2

• But he was not concerned about the impacts

• Carbon dioxide monitoring: CO2 levels have been monitored on Mauna Loa, Hawaii since 1958• Atmospheric CO2 levels have increased 1.5–2 ppm/yr


Carbon dioxide levels

• CO2 levels oscillate 5–7 ppm, reflecting seasonal changes in photosynthesis and respiration• Fall through spring: respiration increases CO2 levels

• Spring through fall: photosynthesis decreases CO2

• By 2009, atmospheric CO2 levels = 338 ppm

• 39% higher than before the Industrial Revolution• Higher than in the past 800,000 years

• Fossil fuels increase CO2 levels

• 1 kg of fossil fuel burned releases 3 kg CO2

• Eight billion tons (gigatons, Gt) of fossil fuel carbon/year


Global carbon emissions from fossil fuels


Sources of carbon dioxide• Half of fossil fuel carbon comes from industrialized

nations• Burning forests adds 1.6 Gtc/year• Over the past 50 years, release of carbon has tripled• Half of the carbon is removed by sinks

• Sinks: burning fossil fuels should add 8 GtC/year to the air• But only 3.3 GtC/year are actually added• Carbon sinks (the ocean, biota) absorb CO2

• Oceans take up CO2 by phytoplankton or undersaturation• But there are limitations to uptake

• Forests are valuable for their ability to sequester carbon


Sources of carbon dioxide emissions from fossil fuels


Global carbon cycle


Other gases

• Other gases absorb infrared radiation• Adding to the insulating effect of carbon dioxide• Most are anthropogenic sources and are increasing

• Water vapor: the most abundant GHG• Its tropospheric concentration varies, but is rising• Higher temperatures increase evaporation and water

vapor (humidity)• Higher humidity traps more heat, causing more

warming (positive feedback)


Other GHGs

• Methane: 20 times more effective than CO2 in heating• From microbial fermentation (in wetlands), green plants• Two-thirds of emissions are from human sources:

livestock, landfills, coal mines, natural gas, rice cultivation, manure

• Rising at 0.8 ppb/year, it is more abundant than in the past 800,000 years

• Nitrous oxide: has increased 18% over the last 200 years• From agriculture, oceans, biomass burning, fossil fuel

burning, industry, anaerobic denitrification (fertilizers)• Warms the troposphere and destroys stratospheric ozone


Ozone and CFCs• Ozone: a short-lived but potent GHG in the

troposphere• From sunlight acting on pollutants• Has increased 36% since 1750• From traffic, forest fires, agricultural wastes

• CFC and other halocarbons are entirely anthropogenic• Long-lived GHGs causing warming and ozone

destruction• From refrigerants, solvents, fire retardants• They absorb 10,000 times more infrared energy than

CO2

• Levels are slowly declining but will remain for decades


Radiative forcing


Future changes in climate• Happening now: higher temperatures, rising seas,

heat waves, droughts, intense storms, season shifts, melting ice

• GHG levels are rising• Along with fossil fuel demand and population• Emissions will rise 35% (2030) and 100% (2050)

• Modeling global climate: computing power has increased• Can explore the potential future impacts of rising

GHGs

• Atmospheric-ocean general circulation models (AOGCMs)• Simulate long-term climatic conditions


Modeled vs. actual data on temperature anomalies (1900–2000)


Testing AOGCMs• The best test: how well they simulate present-day

climate• The most recent models have unprecedented realism

• Assumptions about GHG emissions are combined with climate responses to GHGs (climate sensitivity)• Every scenario showed increased CO2 and

temperature• Future temperature increases will be due to released

energy from the oceans (0.1°C/decade)

• The AR4 report and the models show that increasing GHGs will increase temperatures• Leading to regional climate changes and rising sea

levels


Model projections of global mean warming


Significant findings of climate models• Equilibrium climate sensitivity: if atmospheric CO2

stays at 550 ppm (double preindustrial values), temperature will rise 3°C (2°–4.5°C) by 2050

• Warming will be due to GHG emissions (0.2°C/decade)

• Higher latitudes and continental interiors will warm most• But it will be warmer everywhere

• Snow cover and sea ice will decrease, opening up the Arctic Ocean by 2100• Shrinking glaciers and ice caps will increase sea levels• 90% of upper permafrost will thaw


More findings

• Warmer, dilute upper layers of the North Atlantic Ocean will lead to decreased (but not collapsed) thermohaline circulation

• Increased storm intensities, higher wind speeds and waves, more intense precipitation

• More frequent, longer-lasting heat waves• Longer growing seasons, shorter frost days

• Dry areas will get dryer, wet areas will get wetter• Extreme droughts will affect up to 30% of the world

• Ecosystems (polar ecosystems, coral reefs, rainforests) will be profoundly affected, increasing species extinctions


Global warming impacts on biological systems


The “business as usual” approach

• Predicts 3–5°C temperature increase• 5°C: difference between an ice age and warm period

• Earth’s climate will change dramatically if nothing is done • Responding will involve unprecedented and costly

adjustments• The agricultural community does not know what to

expect• Farmers already lose one in five crops due to weather

• How far will sea levels rise?• 0.5 m: people will abandon flooded coastal areas• 1 m: tens of millions of refugees, lost rice lands,

obliterated low islands


What about the Antarctic?

• The Antarctic could be a huge factor in rising sea levels• The WAIS is shrinking

• Greenland and Antarctic ice sheets hold enough water to raise sea levels 230 feet

• Snowfall has not changed in the past 50 years• 87% of the 244 glaciers are melting• The melting ice sheet is raising sea levels 0.4

mm/year• Higher continental temperatures (3°C)

• Models project a 5% snowfall increase for each 1°C temperature rise


Climate change in the U.S.

• The 2002 Global Change Research Program (GCRP)• Integrates efforts of federal agencies to understand

climate change• Communicates scientific findings to policy makers and

the public• These reports are well done

• Global Climate Change Impacts in the United States• Is designated the United Synthesis Product (USP)• Looks at impacts of climate change on sectors

(health, etc.) and regions (Northwest, Alaska, etc.)


Climate change in the U.S.

• All impacts are expected to continue and/or increase• Impacts are greater in Alaska than any other U.S.

region• Changes in the U.S. over the past 50–100 years

include• Average temperature has risen 2°F• Wetter areas are wetter, dryer areas are dryer• Heavy downpours and storms have increased• More extreme and frequent weather events• Stronger Atlantic hurricanes• Sea levels have risen 2–5 inches• Arctic sea ice is declining rapidly


Climate on the move in the Midwest


Response to climate change

• Industries and transportation network are locked into using fossil fuels• Massive emissions of GHGs will continue

• Adaptation: anticipate harm and plan adaptive responses to decrease vulnerability of people, property, and the biosphere

• Mitigation: take action to prevent emissions• Skeptics about global warming exist• Fossil fuel industry, Rush Limbaugh, conservative

think tanks, some scientists


Stages of climate change skeptics

• Stage I: you’re wrong about climate change and we can prove it• But there are no other plausible arguments for climate

change

• Stage II: OK, the climate is changing, but it isn’t changing that much• The threat is overplayed• Why take costly steps to prevent it?

• Stage III: it will do damage, but it’s too late or too costly to do anything about it


Skeptics and ethical principles

• Climate change skeptics are on talk radio, on the Internet, in Congress, in the media• Unfounded skepticism is regrettable, dangerous, and

unethical

• Precautionary principle: the 1992 Rio Declaration states that lack of scientific certainty should not prevent action

• Polluter pays principle: polluters should pay for the damage they cause

• Equity principle: the rich and privileged should care about the poor


Mitigation• It will be costly to mitigate and adapt to climate

change• But inaction will be far more costly

• Every country will be affected, but especially the poorest• Hundreds of millions of climate refugees• Radicalized people will turn to conflict and terrorism

• The Natural Resources Defense Council estimates inaction will cost the U.S. 3.6% of GDP ($3.8 trillion)• Worldwide costs will equal 5%–20% of GDP/year

• We must reduce emissions of GHGs• What should we target?


Achieving stabilization

• The Framework Convention on Climate Change (FCCC)• We must stabilize GHG levels on a time scale that

prevents interfering with climate• 3°C rise: rising sea levels of 80 feet• 2°C rise: irreversible melting of the Greenland Ice

Sheet

• We have a target of 1–1.5°C more warming• CO2 = 400–500 ppm

• Al Gore’s inconvenient truth: carbon emissions must fall from 8 GtC/year to 2 GtC/year


CO2 emissions and temperature increases for a range of stabilization levels


What has been done?

• The Framework Convention on Climate Change (FCCC) agreed to stabilize GHG emissions to 1990 levels by 2000 in all industrialized nations

• This voluntary approach failed• All developed countries (except the EU) increased

GHG emissions by 7%–9%• Developing countries increased theirs by 25%!

• Kyoto Protocol: the third Conference of Parties to the FCCC met in 1997 in Japan to craft a binding agreement on reducing emissions


The Kyoto Protocol

• 38 industrial nations agreed to reduce GHG emissions 5% below 1990 levels• Annex I parties: signatories to this agreement• Non-Annex I parties: developing countries

• Developing nations refused any reductions• They said they have the right to develop using fossil

fuels, just as developed nations had

• FCC principle of “common but different responsibilities”• Each nation must address climate change• But its priorities and efforts could differ


Ratifying the Kyoto Protocol

• At least 55 nations must ratify it; 180 parties have• The U.S. is the only Annex I party that has not

• Signers of the protocol have flexibility in how they will achieve their GHG reductions• Renewable fuels, nuclear, conservation, planting

trees• Emissions trading, helping other nations

• There are penalties for failing to meet commitments• Many Annex I countries are on target• But not the U.S., Australia, Canada, Japan


Weaknesses of the Kyoto Protocol• The protocol’s targeted reductions will not stabilize

GHGs• It would take immediate reductions of 60% globally• There is no chance of this happening, so emissions will

continue to rise

• The world’s largest GHG emitters are not participating• India, China, the U.S.

• A 2007 UN-sponsored climate conference occurred in Bali• The U.S. and some developing countries opposed

emission cuts and targets• Negotiations on emissions occurred in Copenhagen

(2009)


U.S. policy: the Bush years

• President G. W. Bush opposed the Kyoto Protocol• It exempts developing countries• It would seriously harm the U.S. economy• There was incomplete scientific knowledge

• The U.S. formally withdrew from the Kyoto agreement

• Global Climate Change Initiative (GCCI)• Reduces emissions intensity: the ratio of emissions to

economic output (GDP)• GHG emissions actually rose 17%


U.S. greenhouse gas emissions,1990–2007


Other Bush actions on climate change

• Climate Change Science Program (CCSP/GCRP)• $37 billion since 2001 to research climate change

• But Bush’s administration hampered science and policy• The EPA did not act on a Supreme Court decision

ordering it to consider GHG pollution as a threat• It stifled communications from climate scientists• It heavily edited reports from federal agencies to

emphasize uncertainties

• In 2008, Bush called for limiting GHGs by 2025• Allowing emissions to rise 10% more


A sea change

• The Democratically controlled 110th and 111th Congress addressed climate change issues• The House Select Committee on Energy

Independence and Global Warming• Research, cap-and-trade, emissions taxes

• President Obama has made climate change a priority• Appointed climate scientists to key positions• Nobel Prize-winning physicist Steven Chu heads the

Department of Energy


States and corporations• Many states are acting to address climate change• Renewable portfolio standards, emission reporting• Cap-and-trade programs, reducing emissions• Regional, state, local initiatives will pressure the

federal government to act

• The U.S. Climate Action Partnership: corporations are joining environmental groups urging Congress to act

• Cap-and-trade programs: government sets GHG limits• A company emitting less can sell its unused permits• Already used in the EU and by Annex I parties


Mitigation tools

• Reducing GHG emissions (several are already in place)• Cap-and-trade, renewable energy, carbon capture and

storage, nuclear, reforestation, efficiency• Mileage standards, subsidies, carbon tax

• Stabilization triangle: carbon savings by reducing GHGs• It is broken into seven wedges (mitigation strategies)• Each wedge reduces 1 billion tons of carbon emissions

• 15 wedge strategies in four categories: efficiency/ conservation, fossil fuels, nuclear, renewables• Only seven are needed to bring about the desired

future


Stabilization wedges


Adaptation• Adaptation: making adjustments in anticipation of

changes caused by rising sea levels and temperatures• Reducing vulnerability to impacts• Hard to anticipate what to do and is not cost free

• Examples of adaptation strategies• Agriculture: climate-resistant crops, irrigation• Structures: seawalls, reservoirs, revegetation of

coasts• Emergency preparedness: early-warning systems• Reducing risks: financial safety nets, proper insurance• Development, controlling diseases, economic

progress


New funds

• Climate change will impact developing nations the most

• The FCCC established funding sources to help developing countries• Least Developed Countries Fund: advises countries

on national adaptation strategies• Special Climate Change Fund: provides financial

assistance to countries affected by climate change• Adaptation Fund• Climate Investment Funds: sponsored by the World

Bank


Poverty and climate change• Poverty and Climate Change: Reducing the

Vulnerability of the Poor through Adaptation—a World Bank report• The poor will suffer disproportionately

• Climate changes will be superimposed on other problems• Water, food security, health, life in coastal areas

• Countries with the fewest resources will bear the greatest burden

• Ecosystem goods and services will be disrupted• 96% of disaster-related deaths occur in developing

nations• Adaptation must also reduce poverty and achieve

MDGs


Strategies

• Adaptation strategies will vary with different circumstances

• The best way to address impacts on the poor: integrating adaptation into development and poverty reduction strategies

• Adaptations have “no regrets” benefits• These measures foster desirable social benefits,

regardless of whether climate change is occurring• Improved governance, assessing vulnerability,

accurate information, including economic processes

• Many adaptation strategies are common to all countries


Geoengineering

• Futuristic schemes to fight climate change may not work• Fertilizing oceans with iron to stimulate

photosynthesis

• Scrubbers to remove and store CO2

• Sulfate particles or satellites to block solar radiation

• These schemes have huge costs and unintended consequences

• We are conducting an enormous global experiment in geoengineering • Our children and their descendants will have to live

with the consequences


CHAPTER 18

Global Climate Change

Active Lecture Questions


The layer of the atmosphere that is closest to the Earth’s surface is the

a. troposphere.b. stratosphere.c. mesosphere.d. thermosphere.

Review Question-1


The layer of the atmosphere that is closest to the Earth’s surface is the

a. troposphere.b. stratosphere.c. mesosphere.d. thermosphere.

Review Question-1 Answer


The Nobel Committee awarded the 2007 Nobel Peace Prize to the IPCC and to

a. President Bill Clinton.b. President Jimmy Carter.c. Vice President Al Gore.d. Vice President Dick Cheney.

Review Question-2


The Nobel Committee awarded the 2007 Nobel Peace Prize to the IPCC and to

a. President Bill Clinton.b. President Jimmy Carter.c. Vice President Al Gore.d. Vice President Dick Cheney.



______ is the influence any particular factor has on the energy balance of the atmosphere-ocean-land system.

a. Global warming

b. Radiative forcing

c. Greenhouse warming

d. Planetary albedo

Review Question-3


______ is the influence any particular factor has on the energy balance of the atmosphere-ocean-land system.

a. Global warming

b. Radiative forcing

c. Greenhouse warming

d. Planetary albedo



Which of the following is an observed change that supports the concept of climate change?

a. shrinkage of Arctic sea ice

b. patterns of precipitation are changing

c. marine fish species are shifting northward

d. all of the above

Review Question-4


Which of the following is an observed change that supports the concept of climate change?

a. shrinkage of Arctic sea ice

b. patterns of precipitation are changing

c. marine fish species are shifting northward

d. all of the above



All of the following are anthropogenic greenhouse gases except

a. carbon dioxide.

b. molecular oxygen.

c. chlorofluorocarbons (CFCs).

d. methane.

Review Question-5


All of the following are anthropogenic greenhouse gases except

a. carbon dioxide.

b. molecular oxygen.

c. chlorofluorocarbons (CFCs).

d. methane.



According to Fig. 18-16, which world region is the greatest source of carbon dioxide emissions from fossil fuel burning?

a. Africa

b. Middle East

c. Asia/Pacific

d. North America

Interpreting Graphs and Data-1


According to Fig. 18-16, which world region is the greatest source of carbon dioxide emissions from fossil fuel burning?

a. Africa

b. Middle East

c. Asia/Pacific

d. North America

Interpreting Graphs and Data-1 Answer


According to Fig. 18-22, ifwe meet the higher emissionsscenario for climate change, then Illinois will have summer temperatures similar to ______ by ______.

a. Louisiana; the mid-centuryb. Texas; the mid-centuryc. Louisiana; the end of

the centuryd. Texas; the end of

the century

Interpreting Graphs and Data-2


According to Fig. 18-22, if we meet the higher emissions scenario for climate change, then Illinois will have summer temperatures similar to ______ by ______.

a. Louisiana; the mid-centuryb. Texas; the mid-centuryc. Louisiana; the end of

the centuryd. Texas; the end of

the century

Interpreting Graphs and Data-2 Answer


Under the ______, the government imposes strict limits on emissions from a group of industries and then grants permits for emissions.

a. Climate Change Science Programb. Global Climate Change Initiativec. Cap and Trade Programd. Framework Convention on Climate

Change

Thinking Environmentally-1


Under the ______, the government imposes strict limits on emissions from a group of industries and then grants permits for emissions.

a. Climate Change Science Programb. Global Climate Change Initiativec. Cap and Trade Programd. Framework Convention on Climate

Change

Thinking Environmentally-1 Answer


All of the following are strategies that developed countries can use to better cope with climate change except

a. emergency preparedness.b. have farmers shift to climate-resistant

crops.c. establish a financial safety net and

discourage poor choices.d. increase deforestation.

Thinking Environmentally-2


All of the following are strategies that developed countries can use to better cope with climate change except

a. emergency preparedness.b. have farmers shift to climate-resistant

crops.c. establish a financial safety net and

discourage poor choices.d. increase deforestation.

Thinking Environmentally-2 Answer

© 2011 Pearson Education, Inc. CHAPTER 18 Global Climate Change.

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Transcript of © 2011 Pearson Education, Inc. CHAPTER 18 Global Climate Change.