Global Changes II

Global Changes IIGlobal Changes II

Global Temperature ChangeGlobal Temperature ChangeGlobally, the 10 hottest years on record have occurred Globally, the 10 hottest years on record have occurred since 1991(since 1991(ScienceScience [2004] 303:176). Temperatures have [2004] 303:176). Temperatures have risen 0.6risen 0.6°C in the past 100 years, and global sea levels °C in the past 100 years, and global sea levels have risen ~20 cmhave risen ~20 cm because of melting ice and thermal because of melting ice and thermal expansion of the oceans.expansion of the oceans.

Large icebergs have Large icebergs have recently been breakingrecently been breakingoff of Antarctica.off of Antarctica.

Arctic surfaces have warmed Arctic surfaces have warmed 550 0 C in the last 100 years. C in the last 100 years.

Global Temperature ChangeGlobal Temperature Change

In less than 200 years the atmospheric concentration of In less than 200 years the atmospheric concentration of greenhouse gases has increased by 50% relative to pre-greenhouse gases has increased by 50% relative to pre-industrial levels. Three socioeconomic scenarios industrial levels. Three socioeconomic scenarios indicate in the best case scenario by 2080 risk of floods indicate in the best case scenario by 2080 risk of floods will increase 30x present levels. In the high emission will increase 30x present levels. In the high emission scenario by 2080 flood levels expected once every 100 scenario by 2080 flood levels expected once every 100 years would recur every 3 years.years would recur every 3 years.

In Britain, usage of the Thames In Britain, usage of the Thames Barrier, which protects London Barrier, which protects London from flooding, has increased from from flooding, has increased from less than once a year in the 1980s less than once a year in the 1980s to more than 6 times a year in to more than 6 times a year in 2003.2003.

Global Temperature ChangeGlobal Temperature ChangeReducing carbon emissions does not necessarily equate Reducing carbon emissions does not necessarily equate with lower standards of living. Between 1990 and 2000, with lower standards of living. Between 1990 and 2000, Britain’s economy grew by 30%, employment grew by Britain’s economy grew by 30%, employment grew by 4.8%, and greenhouse gas emission fell by 12% due to use 4.8%, and greenhouse gas emission fell by 12% due to use of less fossil fuels. During the same period from 1990 to of less fossil fuels. During the same period from 1990 to 2000 the Chinese economy grew by 60% and emissions 2000 the Chinese economy grew by 60% and emissions fell. fell.

However, the USA has not ratified the Kyoto Protocol and However, the USA has not ratified the Kyoto Protocol and has not implemented the emissions goals set by the has not implemented the emissions goals set by the Protocol. The UK is responsible for ~2% of the world’s Protocol. The UK is responsible for ~2% of the world’s emissions, while the USA is responsible for more than emissions, while the USA is responsible for more than 20% (with ~4% of the world’s population).20% (with ~4% of the world’s population).Science Science (2004) 303:176 Climate Change Science: Adapt, Mitigate, or Ignore(2004) 303:176 Climate Change Science: Adapt, Mitigate, or Ignore

Global Temperature ChangeGlobal Temperature ChangeProjections for increased global temperatures up to 5Projections for increased global temperatures up to 50 0 C in C in the next 100 years. (This is equal to a temperature change the next 100 years. (This is equal to a temperature change between the waxing and waning of ice ages.)between the waxing and waning of ice ages.)

The Gases of Global WarmingThe Gases of Global WarmingThere are five main greenhouse gases (plus water and ozone). There are five main greenhouse gases (plus water and ozone). COCO22 and CH and CH44 have not been this high in 160,000 years. have not been this high in 160,000 years.

Anthropogenic Causes of Global WarmingAnthropogenic Causes of Global Warming

The Gases of Global Warming:The Gases of Global Warming:

Carbon dioxide: Carbon dioxide: 50% of the effect of global warming. 50% of the effect of global warming. Fossil fuel, deforestation, agriculture, and industry.Fossil fuel, deforestation, agriculture, and industry.MethaneMethane:: 16%. Rice paddies, bogs, termites/deforest, 16%. Rice paddies, bogs, termites/deforest,

landfills, cattlelandfills, cattleChlorofluorocarbons: Chlorofluorocarbons: 20%. Freon, styrofoam, 20%. Freon, styrofoam,

propellants. propellants. Nitrous oxide (NNitrous oxide (N22O): O): 6%. From fertilizers, livestock 6%. From fertilizers, livestock

wastes, fuel combustion.wastes, fuel combustion.Ozone (OOzone (O33): ): 8%. 8%. TroposphericTropospheric ozone is a secondary air ozone is a secondary air pollutant caused by photochemical reactionspollutant caused by photochemical reactions.

Sources of COSources of CO22 Emission and Increases in Emission and Increases in COCO22 During The Last 5 Decades. During The Last 5 Decades.

Greenhouse GasGreenhouse Gas Pre-Indus.Pre-Indus. 19971997 GH WarmingGH Warming

Carbon Dioxide Carbon Dioxide 288 ppm 288 ppm 367 ppm 367 ppm ~50%~50%MethaneMethane 848 ppb848 ppb 1745 ppb1745 ppb 15-20%15-20%ChlorofluorocarbonChlorofluorocarbon 00 262 ppt262 ppt 15-20%15-20%Nitrous OxideNitrous Oxide 285 ppb285 ppb 533 ppb533 ppb 5-6%5-6%Tropospheric OzoneTropospheric Ozone ~8%~8%

Human Activities That Cause Global Human Activities That Cause Global WarmingWarming

Global Circulation ModelsGlobal Circulation ModelsPredict the changes in movement of Predict the changes in movement of surface watersurface water, , groundwatergroundwater, , ocean circulationocean circulation, , atmospheric circulationatmospheric circulation, , andand cloud covercloud cover. .

The surface of the earth is divided into 520 cells (size of Oregon) by 20 cells deep. Each cell interacts with the cells adjacent to it.

Possible Feedbacks To Global Warming Possible Feedbacks To Global Warming

1.1. Greenland and Antarctic ice sheets = large mirrors, Greenland and Antarctic ice sheets = large mirrors, reflecting light into space and cooling the planet. reflecting light into space and cooling the planet. Melting of this ice couldMelting of this ice could cause greater warming. cause greater warming.

2.2. Increased water in air could cause less light penetration Increased water in air could cause less light penetration and and decrease warming. decrease warming. But if cirrus clouds, it could But if cirrus clouds, it could increase global warmingincrease global warming..

3.3. Increased temperatures could Increased temperatures could cause more snow on ice sheets, cause more snow on ice sheets, thereby thereby decreasing global decreasing global warming.warming.

Possible Feedbacks To Global Warming Possible Feedbacks To Global Warming 4. Ocean Conveyor Belt,, which transports heat from the which transports heat from the

tropics to the northern hemisphere. Warming of northern tropics to the northern hemisphere. Warming of northern oceans will change pattern producing:oceans will change pattern producing:

-Cooling in Cooling in Europe and Europe and warming in the warming in the tropics. tropics.

-Decreased -Decreased carbon dioxide carbon dioxide uptake into uptake into oceans, causing oceans, causing greater global greater global warmingwarming..

The Effects of Global WarmingThe Effects of Global WarmingRising Sea LevelRising Sea Level

Flood coastal cities. Flood coastal cities. Salt intrusion could contaminate coastal aquifersSalt intrusion could contaminate coastal aquifers

Changes in Precipitation Pattern and TemperatureChanges in Precipitation Pattern and TemperatureIncreased hurricanes and typhoons.Increased hurricanes and typhoons.Some areas will become drier, some wetter.Some areas will become drier, some wetter.

Effects of Global Warming On Living Effects of Global Warming On Living OrganismsOrganisms

1. 1. Increase bacterial decay, which could exacerbate Increase bacterial decay, which could exacerbate global warming.global warming.

2.2. Increase the spread of diseases: malaria, encephalitis.Increase the spread of diseases: malaria, encephalitis.3. 3. Increased invasion of pest species (Med. fruit fly).Increased invasion of pest species (Med. fruit fly).4. 4. Coral bleaching due to increased stress/disease.Coral bleaching due to increased stress/disease.


5. 5. Fish death due to increased water temps (or loss of Fish death due to increased water temps (or loss of oxygen from increased algae growth) (trout oxygen from increased algae growth) (trout bass and bass and catfish).catfish).

6. 6. Canada and Russia may increase agricultural Canada and Russia may increase agricultural productivity, while tropical countries have declining productivity, while tropical countries have declining productivity. productivity.

7. 7. Fast climate change could cause plant and animal Fast climate change could cause plant and animal species not to be able to migrate to changing climates.species not to be able to migrate to changing climates.


Effects of Global Warming In IndianaEffects of Global Warming In Indiana

Increased precipitation, but increased temperatures will Increased precipitation, but increased temperatures will cause greater evaporation, so cause greater evaporation, so lake and river levels will lake and river levels will declinedecline..

Effects: Effects: Locks/Dams, Ship Docks.Locks/Dams, Ship Docks.HydropowerHydropowerWater QualityWater QualityDeclining Corn YieldsDeclining Corn Yields

How Can We Deal With Global WarmingHow Can We Deal With Global Warming

Prevention of Global WarmingPrevention of Global Warming:: Kyoto ProtocolKyoto Protocol of 1997: legally binding timetables to cut of 1997: legally binding timetables to cut

emissions of greenhouse gases.emissions of greenhouse gases.Alternatives to hydrocarbons must be found/used. Alternatives to hydrocarbons must be found/used. Trapping COTrapping CO22 instead of being released instead of being released

(need new capturing technologies)(need new capturing technologies)

Mitigation of Global WarmingMitigation of Global Warming:: Increase forest planting (area size of U.S. planted/year to Increase forest planting (area size of U.S. planted/year to

totally offset deforestation and COtotally offset deforestation and CO22 emissions) emissions) Pay tropical countries for Pay tropical countries for keepingkeeping forests. forests. Increase energy efficiencyIncrease energy efficiency

Adaptation to Global Warming:Adaptation to Global Warming:Dikes and leveesDikes and leveesDrought resistance plants and trees.Drought resistance plants and trees.

Ozone Depletion in the StratosphereOzone Depletion in the Stratosphere

Ozone absorbs UV radiation.Ozone absorbs UV radiation. Other chemicals that will Other chemicals that will absorb UV include DNA, but DNA is often mutated in the absorb UV include DNA, but DNA is often mutated in the process.process.

Ozone Depletion In The StratosphereOzone Depletion In The Stratosphere

Chemical Causes of Ozone DepletionChemical Causes of Ozone Depletion

1. 1. Chlorofluorocarbons (CFCs)Chlorofluorocarbons (CFCs) - CF - CF22ClCl22 - freon, - freon, propellants, styrofoam. Non-reactive, non-corrosive, non-propellants, styrofoam. Non-reactive, non-corrosive, non-toxic, non-flammable.toxic, non-flammable.

2. 2. HalonsHalons - Fire extinguishers. Bromine compounds. - Fire extinguishers. Bromine compounds.

3. 3. Methyl bromideMethyl bromide - Fumigant in agriculture. - Fumigant in agriculture.

4. 4. Methyl chloroformMethyl chloroform - 1,1,1 trichloroethane. Degreaser. - 1,1,1 trichloroethane. Degreaser.

5. 5. Carbon tetrachlorideCarbon tetrachloride - Pesticides - Pesticides

How Ozone Depletion Takes PlaceHow Ozone Depletion Takes Place

CFCs are usually stable, but UV is high energy and can CFCs are usually stable, but UV is high energy and can break the chlorine bond. Chlorine can react with ozone, break the chlorine bond. Chlorine can react with ozone, converting it to Oconverting it to O22 and ClO. ClO can react with ozone, and ClO. ClO can react with ozone, producing Oproducing O22 again. again.

How Ozone Depletion Takes PlaceHow Ozone Depletion Takes PlaceChlorine can be bound up in water soluble molecules - Chlorine can be bound up in water soluble molecules - HCl and lost to rain, but 100-10,000 molecules of ozone HCl and lost to rain, but 100-10,000 molecules of ozone can be destroyed before it occurs. can be destroyed before it occurs.

But, But, Ozone ‘holes’Ozone ‘holes’ can occur when cold can occur when cold temperatures allow temperatures allow chlorine to be chlorine to be isolated out of isolated out of protective reservoir protective reservoir molecules. Adheres molecules. Adheres to ice crystals and to ice crystals and can react with ozone can react with ozone more more readily.

Effects of Ozone DepletionEffects of Ozone Depletion(1-5% loss of ozone per decade, depending on the estimate). (1-5% loss of ozone per decade, depending on the estimate). Dramatic increases in UV-B radiation (In New Zealand, 12% Dramatic increases in UV-B radiation (In New Zealand, 12% greater in a decade).greater in a decade).

1. Skin cancer, cataracts, 1. Skin cancer, cataracts, weakened immunity to weakened immunity to diseases diseases

2. 2. Ecosystem disruption:Ecosystem disruption: Damages phytoplankton, Damages phytoplankton, reducing their productivity, reducing their productivity, effecting rest of food web effecting rest of food web (p.76)(p.76)

Protecting the Ozone Layer - Protecting the Ozone Layer - Alternatives to CFCsAlternatives to CFCs

Montreal Protocol:Montreal Protocol: treaty to decrease/eliminate CFCs.treaty to decrease/eliminate CFCs.

1985:1985: 917,000 metric tons CFCs 917,000 metric tons CFCs

1997:1997: 56,500 metric tons 56,500 metric tons

HydrofluorocarbonsHydrofluorocarbons - not ozone destroyer (but is a - not ozone destroyer (but is a greenhouse gas).greenhouse gas).

HydrochlorofluorocarbonsHydrochlorofluorocarbons - shorter lived, but still can - shorter lived, but still can deplete ozone.deplete ozone.

Measuring Acidity - pHMeasuring Acidity - pHpH = negative log of the hydrogen ion concentration in a pH = negative log of the hydrogen ion concentration in a solution. solution. Each unit has 10x change in acidity. Each unit has 10x change in acidity.

Rain: normally a pH of 5 to 6—because of CORain: normally a pH of 5 to 6—because of CO22 dissolved in dissolved in the water makes carbonic acid. But in Eastern US, pH of the water makes carbonic acid. But in Eastern US, pH of rainwater can be 4 or even 3.rainwater can be 4 or even 3.

Origins of Acid DepositionOrigins of Acid DepositionNitrogen oxidesNitrogen oxides - vehicles and industry - vehicles and industrySulfur oxidesSulfur oxides - power plants, smelters, industrial boilers - power plants, smelters, industrial boilers

Effects of Acid Effects of Acid DepositionDeposition

a.a. Leaching of nutrients Leaching of nutrients from soil (calcium and from soil (calcium and magnesium) and magnesium) and increasing heavy metals increasing heavy metals (aluminum), which causes (aluminum), which causes poorer tree growth.poorer tree growth.

b.b. Acidity of soil also Acidity of soil also damages roots. Damage damages roots. Damage to leaves and bark due to to leaves and bark due to acidity.acidity.

1.1. Forest declineForest decline::

Effects of Acid DepositionEffects of Acid Deposition

1.1. Forest declineForest decline::

Black forest of Germany:Black forest of Germany: up to 50% of trees are dead or up to 50% of trees are dead or severely damaged.severely damaged.

Cloud water in Cloud water in eastern U.S. is 5 eastern U.S. is 5 times more times more acidic than acidic than precipitation. precipitation. Trees in high Trees in high altitudes are altitudes are bathed in this.bathed in this.

Effects of Acid DepositionEffects of Acid Deposition2. 2. Aquatic animal declines in rivers and lakes:Aquatic animal declines in rivers and lakes:

Dramatic differences in tolerance limits: From mussels and Dramatic differences in tolerance limits: From mussels and mayflies, which are intolerant to low pH, to some insects that mayflies, which are intolerant to low pH, to some insects that are very tolerant to pH.are very tolerant to pH.

Effects of Acid DepositionEffects of Acid Deposition2. 2. Aquatic animal declines in rivers and lakes:Aquatic animal declines in rivers and lakes:

Sweden has 3000 to 4000 dead Sweden has 3000 to 4000 dead lakes. Lakes without fish, frogs, lakes. Lakes without fish, frogs, or lily pads. Acidification can or lily pads. Acidification can cause toxic metals to be leached cause toxic metals to be leached from sediments in lakes into the from sediments in lakes into the water. Similar risks for lakes in water. Similar risks for lakes in the Adirondacks.the Adirondacks.

Depends on the presence or Depends on the presence or absence of buffering agents in absence of buffering agents in the bedrock surrounding or the bedrock surrounding or underlying lakes - carbonates.underlying lakes - carbonates.

Politics of Acid DepositionPolitics of Acid Deposition

Regional issues. Pollution in Sweden is from other European Regional issues. Pollution in Sweden is from other European countries. Similarly, pollution from Illinois, Indiana, countries. Similarly, pollution from Illinois, Indiana, Missouri, West Virginia, Ohio, Penn causes acid deposition Missouri, West Virginia, Ohio, Penn causes acid deposition in New England and Canada.in New England and Canada.

Controlling Acid DepositionControlling Acid DepositionReduction of emissions (e.g., Clean Air Act of 1990)Reduction of emissions (e.g., Clean Air Act of 1990)

Conversion of sulfur and nitrogen oxides into acids is also Conversion of sulfur and nitrogen oxides into acids is also affected by availability of ozone and other emissions which affected by availability of ozone and other emissions which help cause the chemical reactions.help cause the chemical reactions..

Almost 15% of the world's reefs are already beyond repair thanks to global warming, according to an AAAS report. Another 30% may be lost over the next 30 years. Global warming is Global warming is harming coral reefs in at least three harming coral reefs in at least three ways. Changes of just 1 or 2 °C can ways. Changes of just 1 or 2 °C can stifle the life-giving algae. Spiraling stifle the life-giving algae. Spiraling levels of carbon dioxide, a greenhouse levels of carbon dioxide, a greenhouse gas, dissolve in sea water, creating an gas, dissolve in sea water, creating an acidic cocktail that stops polyps acidic cocktail that stops polyps oozing their skeleton. And warmer oozing their skeleton. And warmer water makes the reef more vulnerable water makes the reef more vulnerable threats, such as overfishing, diseases threats, such as overfishing, diseases and pollutants that drain into coastal and pollutants that drain into coastal waters.waters.

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Global Changes II