Climate Change and Climate Change and Ozone LossOzone Loss

Chapter 16Chapter 16

Studying a Volcano to Studying a Volcano to Understand Climate ChangeUnderstand Climate Change

Mt. Pinatubo, PhilippinesMt. Pinatubo, Philippines

1991 eruption1991 eruption

Temporary world coolingTemporary world cooling

Climate modelingClimate modeling

Hansen’s modelHansen’s model

Fig. 16-1, p. 367

Past Climate ChangesPast Climate Changes

Past global temperaturesPast global temperatures

Causes of climatic changesCauses of climatic changes

Glaciations and warmer interglacial periodsGlaciations and warmer interglacial periods

Earth’s natural greenhouse effect (Fig. 5-5, p. 82)Earth’s natural greenhouse effect (Fig. 5-5, p. 82)

Thousands of years ago

Ave

rag

e su

rfac

e te

mp

erat

ure

(°C

)

900 800 700 600 500 400 300 200 100 Present9

10

11

12

13

14

15

16

17

Fig. 16-2a, p. 369

Average Global Temperature Average Global Temperature over the Past 900,000 Yearsover the Past 900,000 Years

End oflast iceage

Fig. 16-2b, p. 369

Temperature Changes Over Past Temperature Changes Over Past 22,000 Years22,000 Years

Years ago

Tem

per

atu

re c

han

ge

(°C

)

– 4

– 3

– 2

–1

0

1

2Agriculture established

Average temperature over past10,000 years = 15°C (59°F)

20,000 10,000 2,000 1,000 200 100 Now

– 5

Year

Tem

per

atu

re c

han

ge

(°C

)

1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2101

–1.0

–0.5

0.0

0.5

1.0

Fig. 16-2c, p. 369

Temperature Changes Over Past Temperature Changes Over Past 1,000 Years1,000 Years

Year

Ave

rag

e su

rfac

e te

mp

erat

ure

(°C

)

1860 1880 1900 1920 1940 1960 1980 2000 2020

13.6

13.8

14.0

14.2

14.4

14.6

14.8

15.0

Fig. 16-2d, p. 369

Average Global Temperature Average Global Temperature Over Past 130 YearsOver Past 130 Years

Ice Cores: Records of Past ClimatesIce Cores: Records of Past Climates

Fig. 16-3, p. 369

Fig. 5-5, p. 82

(a) Rays of sunlight penetrate the lower atmosphere and warm the earth's surface.

(b) The earth's surface absorbs much of the incoming solar radiation and degrades it to longer-wavelengthinfrared (IR) radiation, which rises into the lower atmosphere. Some of this IR radiation escapes into space as heat and some is absorbed by molecules of greenhouse gases and emitted as even longer wavelength IR radiation, which warms the lower atmosphere.

(c) As concentrations of greenhouse gases rise, their molecules absorb and emit more infrared radiation, which adds more heat to the lower atmosphere.

Greenhouse Effect Greenhouse Effect

Major Greenhouse GasesMajor Greenhouse Gases

Water vaporWater vapor

Carbon dioxide (COCarbon dioxide (CO22))

Methane (CHMethane (CH44))

Nitrous oxide (NNitrous oxide (N22O)O)

Table 16-1, p. 370Table 16-1, p. 370

Table 16-1, p. 370

Fig. 16-4, p. 370

Carbon dioxide

Temperaturechange

End oflast ice age

160 120 80 40 0Thousands of years before present

Co

nce

ntr

atio

n o

f ca

rbo

n d

ioxi

de

in t

he

atm

osp

her

e (p

pm

)

180

200

220

240

260

280

300

320

340

360

380

–10.0

–7.5

–5.0

–2.5

0

+2.5

Var

iati

on

of

tem

per

atu

re (

˚C)

fro

m c

urr

ent

leve

l

Atmospheric Carbon Dioxide and Global Atmospheric Carbon Dioxide and Global Temperatures Temperatures

Climate Change and Human Climate Change and Human ActivitiesActivities

Human emissions of greenhouse gasesHuman emissions of greenhouse gases

US carbon dioxide emissionsUS carbon dioxide emissions

Troposphere warmingTroposphere warming

• 2020thth century warmest in 1000 years century warmest in 1000 years

• Average global temperatures risingAverage global temperatures rising

• 16 warmest years since 198016 warmest years since 1980

• Glaciers and floating sea ice meltingGlaciers and floating sea ice melting

• Melting permafrost and release of more greenhouse gasesMelting permafrost and release of more greenhouse gases

• Rising sea levelRising sea level

Fig. 16-5a, p. 371Carbon dioxide (CO2)Year

1800 1900 2000 2100260

310

360

410

Par

ts p

er m

illi

on

Increases in Average Atmospheric Increases in Average Atmospheric Carbon Dioxide Since 1860Carbon Dioxide Since 1860

Fig. 16-5b, p. 371Methane (CH4)Year1800 1900 2000 2100

0.6

1.2

1.8

2.4

Par

ts p

er m

illi

on

Increases in Average Atmospheric Increases in Average Atmospheric Methane Since 1860Methane Since 1860

Fig. 16-5c, p. 371Year

Par

ts p

er m

illi

on

18001900 2000 2100

260

290

300

310

320

Nitrous oxide (N2O)

Increases in Average Atmospheric Increases in Average Atmospheric Nitrous Oxide Since 1860Nitrous Oxide Since 1860

Shrinking Arctic Sea Ice (1979-2003)Shrinking Arctic Sea Ice (1979-2003)

Fig. 16-6, p. 372

Scientific Consensus on Future Scientific Consensus on Future Climate ChangeClimate Change

Mathematical modelsMathematical models

Model data and assumptionsModel data and assumptions

Predictions of the modelsPredictions of the models

Models indicate most recent warming due to human Models indicate most recent warming due to human activitiesactivities

Very likely Earth’s mean temperature will increase in Very likely Earth’s mean temperature will increase in 2121stst century century

Troposphere

Aerosols

Greenhousegases

Warmingfrom

decrease

Cooling from

increase

CO2 removal by plants and soil

organisms

CO2 emissions from land cleaning, fires, and

decay

Heat andCO2 removal

Heat andCO2 emissions

Ice and snow cover

Natural and human emissions

Land and soil biotoa

Shallow ocean

Long-termstorage

Deep ocean

Fig. 16-7, p. 372

Processes that Determine Average Processes that Determine Average Temperature and Greenhouse Gas ContentTemperature and Greenhouse Gas Content

Fig. 16-8, p. 373

Measured Average Temperatures and Measured Average Temperatures and Future PredictionsFuture Predictions

Concerns about a Warmer EarthConcerns about a Warmer Earth

DroughtsDroughts

Higher sea level and coastal floodingHigher sea level and coastal flooding

Disrupted ecologyDisrupted ecology

Economic and social costsEconomic and social costs

Abrupt changesAbrupt changes

Severe stormsSevere storms

Insects and infectious diseasesInsects and infectious diseases

Factors Affecting the Earth’s Factors Affecting the Earth’s TemperatureTemperature

Ability of oceans to store carbon dioxideAbility of oceans to store carbon dioxide

Local global cooling is possibleLocal global cooling is possible

Effects of cloud coverEffects of cloud cover

Jet contrailsJet contrails

Aerosols: volcanic eruptions and human activitiesAerosols: volcanic eruptions and human activities

Sulfate and black carbon aerosolsSulfate and black carbon aerosols

PhotosynthesisPhotosynthesis

Methane emissions: methane hydratesMethane emissions: methane hydrates

Fig. 16-9, p. 374

Shallow and Deep Ocean CurrentsShallow and Deep Ocean Currents

Fig. 16-10, p. 376

• Decreased deaths from cold weather

• Increased deaths from heat and disease

• Disruption of food and water supplies

• Spread of tropical diseases to temperate areas

• Increased respiratory disease and pollen allergies

• Increased water pollution from coastal flooding

• Increased formation of photochemical smog

Human Health

• Rising sea levels• Flooding of low-lying islands

and coastal cities• Flooding of coastal estuaries,

wetlands, and coral reefs• Beach erosion• Disruption of coastal fisheries• Contamination of coastal

aquifiers with salt water

Sea Level and Coastal Areas

• Changes in forest composition and locations

• Disappearance of some forests, especially ones at high elevations

• Increased fires from drying

• Loss of wildlife habitat and species

Forests•Changes in water supply

•Decreased water quality

• Increased drought

• Increased flooding

•Snowpack reduction

•Melting of mountaintop glaciers

Water Resources

• Shifts in food-growing areas

• Changes in crop yields

• Increased irrigation demands

• Increased pests, crop diseases, and weeds in warmer areas

Agriculture

• Extinction of some plant and animal species

• Loss of habitats

• Disruption of aquatic life

Biodiversity

• Prolonged heat waves and droughts

• Increased flooding from more frequent, intense, and heavy rainfall in some areas

Weather Extremes

• Increased deaths from heat and disruption of food supplies

• More environmental refugees

• Increased migration

Human Population

Benefits and Negative Impacts of Global WarmingBenefits and Negative Impacts of Global Warming

Fig. 16-11, p. 377

Possible Effects of Global Warming Possible Effects of Global Warming on Beech Treeson Beech Trees

Futurerange

Overlap

Presentrange

Beech

Rising Sea Levels Threaten IslandsRising Sea Levels Threaten Islands

Fig. 16-12, p. 377

Why Climate Change is a Why Climate Change is a Difficult ProblemDifficult Problem

Complex causesComplex causes

Global problem: How can we all agree?Global problem: How can we all agree?

Long-term problemLong-term problem

Harmful and beneficial effects of climate change not spread Harmful and beneficial effects of climate change not spread evenlyevenly

Can’t stop climate change, only slow rate and adaptCan’t stop climate change, only slow rate and adapt

Solutions are difficult and controversialSolutions are difficult and controversial

Options to Deal with Climate ChangeOptions to Deal with Climate Change

““Wait and see” strategy: we need more researchWait and see” strategy: we need more research

““Act now” strategyAct now” strategy

““Act now with no regrets” strategyAct now with no regrets” strategy

Global Warming

Solutions

Prevention Cleanup

Cut fossil fuel use (especially coal)

Shift from coal to natural gas

Improve energy efficiency

Shift to renewable energy resources

Transfer energy efficiency and renewable energy technologies to developing countries

Reduce deforestation

Use more sustainable agriculture

Limit urban sprawl

Reduce poverty

Slow population growth

Store (sequester) CO2 by planting trees

Sequester CO2 deep underground

Sequester CO2 in soil by using no-till cultivation and taking crop land out of production

Sequester CO2 in the deep ocean

Repair leaky natural gas pipelines and facilities

Use feeds that reduce CH4 emissions by belching cows

Remove CO2 from smokestackand vehicle emissions

Fig. 16-13, p. 379

Solutions to Global WarmingSolutions to Global Warming

Tree plantationCoal power plant

Tanker deliversCO2 from plantto rig

Oil rig

Crop fieldCrop fieldSwitchgrassSwitchgrass

Spent oil reservoir isused for CO2 deposit

CO2 is pumped down to reservoir through abandoned oil field

Abandonedoil field

CO2 ispumped downfrom rig for deepocean disposal

= CO2 deposit

= CO2 pumping

Fig. 16-14, p. 380

Removing Carbon Dioxide from the Removing Carbon Dioxide from the AtmosphereAtmosphere

Government Roles in Reducing the Government Roles in Reducing the Threat of Climate ChangeThreat of Climate Change

Funding for carbon dioxide removal technologiesFunding for carbon dioxide removal technologies

Carbon taxesCarbon taxes

Energy taxesEnergy taxes

Decreasing other taxesDecreasing other taxes

Leveling the economic playing fieldLeveling the economic playing field

Technology transferTechnology transfer

Kyoto ProtocolKyoto Protocol

What other countries, cities and businesses are doingWhat other countries, cities and businesses are doing

Fig. 16-15, p. 382

Reducing CO2 Emissions

What Can You Do?

• Drive a fuel-efficient car, walk, bike, carpool, and use mass transit

• Use energy-efficient windows

• Use energy-efficient appliances and lights

• Heavily insulate your house and seal all drafts

• Reduce garbage by recycling and reuse

• Insulate hot water heater

• Use compact fluorescent bulbs

• Plant trees to shade your house during summer

• Set water heater no higher than 49°C (120°F)

• Wash laundry in warm or cold water

• Use low-flow shower head

What Can You Do?What Can You Do?

Connect wildlifereserves with corridors

Move hazardous material storagetanks away from coast

Expand existingwildlife reservestoward poles

Stockpile 1- to 5-yearsupply of key foods

Prohibit new constructionon low-lying coastal areasor build houses on stilts

Develop crops thatneed less water

Waste less water

Move people away from low-lyingcoastal areas

Fig. 16-16, p. 382

Preparing for Climate ChangesPreparing for Climate Changes

Ozone Depletion in the StratosphereOzone Depletion in the Stratosphere

Location and purpose of the ozone layerLocation and purpose of the ozone layer

Seasonal and long-term depletion of ozoneSeasonal and long-term depletion of ozone

Causes: chlorofluorocarbons (CFCs) and other chemicalsCauses: chlorofluorocarbons (CFCs) and other chemicals

How CFCs destroy the ozone layerHow CFCs destroy the ozone layer

Rowland and Molina’s researchRowland and Molina’s research

Former Uses of CFCsFormer Uses of CFCs

Coolants in air conditioners and refrigeratorsCoolants in air conditioners and refrigerators

Propellants in aerosol cansPropellants in aerosol cans

Cleaning solutions for electronic partsCleaning solutions for electronic parts

FumigantsFumigants

Bubbles in plastic packing foamBubbles in plastic packing foam

Ozone ThinningOzone Thinning

SeasonalSeasonal

More severe over Antarctica than the ArcticMore severe over Antarctica than the Arctic

ConsequencesConsequences

ModelsModels

Effects of Ozone Depletion

Natural Capital Degradation

Human Health• Worse sunburn• More eye cataracts• More skin cancers• Immune system suppression

Food and Forests• Reduced yields for some crops• Reduced seafood supplies from reduced phytoplankton• Decreased forest productivity for UV-sensitive tree species

Wildlife• Increased eye cataracts in some species• Decreased population of aquatic species sensitive to UV radiation• Reduced population of surface phytoplankton• Disrupted aquatic food webs from reduced phytoplankton

Air Pollution and Materials• Increased acid deposition• Increased photochemical smog• Degradation of outdoor paints and plastics

Global Warming• Accelerated warming because of decreased ocean uptake of CO2 from

atmosphere by phytoplankton and CFCs acting as greenhouse gases

Fig. 16-17, p. 384

Consequences of Ozone LossConsequences of Ozone Loss

Ultraviolet A Ultraviolet B

Thin layer ofdead cells

Squamouscells

Basallayer

Melanocytecells

Basalcell

Bloodvessels

HairEpidermis

Sweatgland

Dermis

Squamous Cell CarcinomaBasal Cell Carcinoma Melanoma

Fig. 16-18a, p. 385

Skin CancersSkin Cancers

Basal Cell Carcinoma

Melanoma

Squamous Cell Carcinoma

DO

NO

T P

OS

T T

O IN

TE

RN

ET

DO

NO

T P

OS

T T

O IN

TE

RN

ET

Fig. 16-18bcd, p. 385

Skin CancersSkin CancersD

O N

OT

PO

ST

TO

INT

ER

NE

T

Fig. 16-19, p. 386

Reducing Exposure to UV-Radiation

What Can You Do?

• Stay out of the sun, especially between 10 A.M. and 3 P.M.

• Do not use tanning parlors or sunlamps.

• When in the sun, wear protective clothing and sun–glasses that protect against UV-A and UV-B radiation.

• Be aware that overcast skies do not protect you.

• Do not expose yourself to the sun if you are taking antibiotics or birth control pills.

• Use a sunscreen with a protection factor of 15 or 25 ifyou have light skin.

• Examine your skin and scalp at least once a month for moles or warts that change in size, shape, or color or sores that keep oozing, bleeding, and crusting over. If you observe any of these signs, consult a doctor immediately.

Reducing Exposure to Ultraviolet RadiationReducing Exposure to Ultraviolet Radiation

Protecting the Ozone LayerProtecting the Ozone Layer

Slow recovery of the ozone layerSlow recovery of the ozone layer

Montreal Protocol: Reducing CFC emissionsMontreal Protocol: Reducing CFC emissions

Copenhagen ProtocolCopenhagen Protocol

International cooperationInternational cooperation

Individuals MatterIndividuals Matter, p. 386: , p. 386: Ray Turner and His Ray Turner and His RefrigeratorRefrigerator