cars and global warming - frontier group

Environment MarylandResearch and Policy Center

September 2006

Policy Options to ReduceMaryland’s Global Warming Pollution

from Cars and Light Trucks

Cars and Global Warming

Cars and Global WarmingPolicy Options to Reduce Maryland’s

Global Warming Pollutionfrom Cars and Light Trucks

Elizabeth RidlingtonBrad Heavner

Environment MarylandResearch and Policy Center

September 2006

Acknowledgments

The authors wish to thank Beth McGee of the Chesapeake Bay Foundation and EdOsann of Potomac Resources, for offering their expertise and providing peer review.Thanks to Dan Meszler of Meszler Associates and Eric Haxthausen of EnvironmentalDefense for reviewing earlier versions of this report.

Sincere thanks to the Energy Foundation for providing financial support for thisproject.

The authors alone bear responsibility for any factual errors. The recommendations arethose of the Environment Maryland Research and Policy Center. The views expressedin this report are those of the authors and do not necessarily reflect the views of ourfunders or those who provided peer or technical review.

© 2006 Environment Maryland Research and Policy Center

Environment Maryland Research and Policy Center is a non-profit organization dedi-cated to protecting Maryland’s air, water and open spaces. We investigate problems,craft solutions, educate the public and decision makers, and help Maryland residentsmake their voices heard in local, state and national debates over the quality of theenvironment and our lives.

For additional copies of this report or more information about Environment Marylandand the Environment Maryland Research and Policy Center, please visit our Web siteat www.EnvironmentMaryland.org/center or call us at 410-467-0439.

Table of Contents

Executive Summary 5

Introduction 8

Global Warming and Maryland 9Global Warming Impacts to Date 9Projected Future Impacts of Global Warming 11Human Activities Are Causing Global Warming 14Global Warming Pollution in Maryland 15Pollution Reduction Efforts in Maryland 16The Transportation Challenge 16Vehicle Carbon Dioxide Pollution in Maryland:Past and Projected 19

Tools to Reduce Global Warming Pollutionfrom Cars and Light Trucks 22LEV II Standards 22Vehicle Global Warming Pollution Standards 26

Policy Recommendations 29Reduce Per-Mile Emissions from Vehicles 29Reduce Growth in Vehicle Travel 30

Assumptions and Methodology 32

Notes 37

4 Cars and Global Warming

Executive Summary 5

Executive Summary

M aryland could limit its contribu-tion to global warming over thenext two decades by implement-

ing policies to reduce carbon dioxideemissions from cars and light trucks. TheClean Cars Program is the best opportu-nity to reduce vehicle emissions of glo-bal warming pollution, and would benefitconsumers and the state economy at thesame time that it reduces pollution.

Global warming poses a seriousthreat to Maryland’s future.Scientists project that average tempera-tures in Maryland could increase by 2°to 9° F over the next century if no actionis taken to reduce global warming pollu-tion. Global warming could flood tens ofthousands of acres around the Chesa-peake Bay, damage water quality in thebay, worsen air quality, and harm Mary-land’s economy, public health and envi-ronment in a host of other ways.

Controlling global warming pollutionfrom the transportation sector—and par-ticularly cars and light trucks—is essen-tial if Maryland is to begin to reduce its

emissions and its long-term impact on theclimate.

Transportation-related emissions areresponsible for approximately 37 percentof Maryland’s emissions of carbon diox-ide, the leading global warming pollut-ant. Cars and light trucks—such aspickups, minivans and SUVs—are themost important sources of global warm-ing pollution within the transportationsector, responsible for approximately 70percent of all emissions from transporta-tion and more than one-quarter ofMaryland’s total emissions of globalwarming pollution.

Pollution is increasing rapidly.Emissions from cars and trucks alreadyhave increased by nearly 32 percent from1990 to 2004 and are projected to rise byan additional 35 percent from 2004 to2020.

The stagnation in federal corporateaverage fuel economy (CAFE) standardsfor cars and light trucks, the recent shifttoward greater use of SUVs, and increas-ing vehicle travel have put Maryland on


a course toward dramatically increasedemissions of carbon dioxide from trans-portation over the next two decades.

The Clean Cars Program wouldgreatly reduce pollution.The Clean Cars Program establishes lim-its on health-damaging pollution and glo-bal warming pollution from automobiles.It will pave the way for the widespreadintroduction of technologies like hybrid-electric and fuel-cell vehicles, direct-in-jection engines, advanced transmissions,improved air conditioning systems, andother technologies with the potential toreduce pollution. The program is madeup of the Low Emission Vehicle II (LEVII) standards for health-damaging pollu-tion and vehicle global warming pollu-tion standards.

By implementing the program to takeeffect in model year 2011 (calendar year2010), Maryland could reduce carbondioxide pollution from cars and lighttrucks by 4.4 million metric tons in 2020.This is 14 percent below projected lev-els. (See Figure ES-1.)

The Clean Cars Program wouldsave consumers money.

One of the central requirements of thevehicle global warming pollution stan-dards is that they be cost-effective. Thetechnological changes needed to achievethe reductions (such as five and six-speedautomatic transmissions and improvedelectrical systems) will likely result inmodest increases in vehicle costs thatwould be more than recouped over timeby consumers in the form of reduced fuelexpenses.

Cars and the lightest light trucks at-taining the 34 percent reduction in glo-bal warming pollution required by 2016would cost an average of $1,064 more forconsumers, while heavier light trucksachieving the required 25 percent reduc-tion would cost about $1,029 more. How-ever, these technological changes willsignificantly reduce operating costs fornew vehicles.

For example, a consumer who buys a newcar in 2016 will save $20 per month dueto lower operating expenses despite thehigher cost of the vehicle loan, assuming

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Figure ES-1. Estimated Maryland Carbon Dioxide Emissions from Cars andLight Trucks, 2004-2020, Under Policy Scenario

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Executive Summary 7

a gas price of three dollars per gallon.After the loan is paid off, the consumerwill save $41 per month. Drivers whopurchase a light truck or who pay for thevehicle in cash will experience greatersavings. Even at lower gas prices, con-sumers save money from day one and theaccumulated savings exceed the increased

Car SUV Car SUV

Annual Net Savings while Repaying Loan $245 $320 $115 $170

Annual Net Savings after Loan Is Repaid $490 $560 $360 $410

Time to Recoup Higher Cost of Vehicle 2.2 years 2.5 years 2.9 years 3.4 years

Gas Price of$3 per Gallon

Gas Price of$2.20 per Gallon

purchase price in only a few years. (SeeTable ES-1.)

The net impact of the standards to thestate’s economy will be positive, suggest-ing that Maryland as a whole could savemoney while at the same time reducingthe state’s overall emissions of globalwarming gases.

Table ES-1. Net Savings for a Consumer Under Global Warming PollutionStandards in 20161

8 Introduction

Introduction

In the past year, Maryland took its firstmajor step toward reducing globalwarming pollution by joining a re-

gional program to curb emissions frompower plants. The Regional GreenhouseGas Initiative will stabilize emissionsfrom power plants from 2009 to 2015 andthen reduce emissions by 10 percent by2018.

But that’s not nearly enough.To avoid the worst impacts of global

warming, climate scientists agree that weneed to reduce global warming pollutionby about 70-85 percent within the nexthalf-century.

To meet this challenge, the world willneed to halt the growth of global warm-ing pollution in this decade, begin reduc-ing emissions soon, and slash emissionsdramatically in the coming decades.2 Be-cause the U.S. is the world’s largest glo-bal warming polluter, the degree ofemission reductions required here will begreater.

The entire path to achieving such pol-lution reductions isn’t yet clear, but thefirst steps are readily apparent. We should

pursue those clearcut policies as quicklyas possible.

The Clean Cars Program would likelyhave an even greater impact on limitingMaryland’s contribution to global warm-ing than the Regional Greenhouse GasInitiative. Since the state has decided itwas worth it to take action on powerplants, it should be even more willing todo so on vehicles. The program will takelittle work for the state to implement, andwill save money for consumers.

In the long run, we need to developmany innovative approaches to reducingglobal warming pollution—building car-bon-neutral communities, keeping busi-ness running with lower transportationneeds, transforming the power system toclean energy sources. The roadmap forthat action will be difficult to write, butthe job will be easier if we act withoutdelay to put the obvious first policies inplace.

Adopting the Clean Cars program isthe best step that Maryland can take im-mediately using current technology to re-duce its contribution to global warming.

Global Warming and Maryland 9

Global Warming Impactsto Date

G lobal warming threatens Mary-land’s future health, well-beingand prosperity. The first signs of

global warming are beginning to appearin Maryland and throughout the world.Global temperatures and sea level are onthe rise. Other changes, such as the re-cent increase in the severity of hurricanes,are consistent with the kinds of changesscientists expect to occur on a warmingplanet and are harbingers of the dramaticclimate shifts that await us if global warm-ing pollution continues unabated.

Rising TemperaturesGlobal average temperatures increasedduring the 20th century by about 1° F.While this increase may not seem ex-treme, it is unprecedented in the contextof the last 1,000 years of world history.4

Figure 1 shows temperature trends in theNorthern Hemisphere for the past 1,000years with a relatively recent upward spike.

Global warming appears to have in-tensified in recent years. In 2006, the

National Aeronautics and Space Admin-istration (NASA) reported that, since1975, temperatures have been increasingat a rate of about 0.36° F per decade.6

The first six months of 2006 were thehottest such period in the U.S. over morethan a century of record-keeping, withtemperatures averaging 3.4° F higherthan the average for the 20th century,while 2005 was the hottest year on recordworldwide.7 Nineteen of the 20 hottestyears ever recorded have occurred since1983 and nine of the 10 hottest years haveoccurred since 1995.8

In Maryland, the average temperatureat the College Park weather station hasrisen by 2.4° F in the past 100 years.9 Datafrom five of eight temperature stationsacross the state show increasing tempera-tures from 1948-1999 and increasingtemperatures at all stations from 1977-1999.10 Precipitation in Maryland hasincreased by 10 percent in many parts ofthe state.11

This warming trend cannot be ex-plained by natural variables—such as so-lar cycles or volcanic eruptions—but itdoes correspond to models of climatechange based on human influence.12

Global Warming and Maryland


Melting IceThe rise in global temperatures has re-sulted in thinning ice and decreasingsnow cover. Over the last three decades,the volume and extent of ice cover in theArctic has been declining rapidly, lead-ing to the possibility that the Arctic couldbe ice-free during the summer by the endof this century.13 Mountain glaciersaround the world have been retreating,and since the late 1960s, Northern Hemi-sphere snow cover has decreased by 10percent.14

Rising Sea LevelOceans have risen with the melting ofglacial ice and the expansion of the oceanas it warms. Average sea level has risen0.1 to 0.2 meters in the past century.15

Sea level rise has already helped cause theinundation of some coastal land. In theChesapeake Bay, 13 islands have disap-peared entirely since the beginning ofEuropean settlement four centuriesago.16 Louisiana loses approximately 24square miles of wetlands each year, caus-ing an increase in the destructive poten-tial of hurricanes like Hurricane

Katrina.17 While development and landsubsidence contribute to the loss ofcoastal land in these areas, rising sea levelalso has an impact, and threatens evengreater changes in coastal areas in thedecades to come.

Sea level near Baltimore has risenseven inches in the past 100 years.18

Maryland’s vulnerability to sea rise is ex-acerbated by a separate trend: the state issinking by more than six inches per cen-tury as it recovers from glaciers that cov-ered the region thousands of years ago.19

The net effect of rising sea level and sink-ing land has been a one-foot increase inwater level in the past 100 years. AlongMaryland’s 3,100 miles of tidally influ-enced shoreline, 260 acres of land is losteach year.20 Thirteen islands in the bayhave disappeared.21 Smith Island has lost30 percent of its land area since 1850. The1,400-acre Poplar Island has disappearedalmost entirely.22

More Severe StormsStorms throughout the middle and highlatitudes of the Northern Hemispherehave been getting more intense. The

Figure 1. Northern Hemisphere Temperature Trends5

Global Warming in Maryland 11

increase in the frequency of heavy pre-cipitation events arises from a number ofcauses, including changes in atmosphericmoisture, thunderstorm activity andlarge-scale storm activity.23

In addition, hurricanes have becomemore powerful and more destructive overthe past three decades, a phenomenonthat some researchers link to increasingglobal temperatures.24 The number ofCategory 4 and Category 5 hurricanesglobally has nearly doubled worldwideover the past 35 years.25 And the Atlantichurricane season of 2005 was the worstever recorded with the most namedstorms (28), the most hurricanes (15), themost Category 5 hurricanes (4), the mostmajor hurricanes to hit the U.S. (4), thecostliest hurricane (Katrina, which causedmore than $80 billion in damage), andthree of the six strongest hurricanes re-corded (Wilma, the strongest ever, plusKatrina and Rita).26

Higher sea level increased the impactof Hurricane Isabel in 2003. HurricaneIsabel followed the same path and hadroughly the same power as a storm in1933.27 That earlier storm, however,caused far less damage, in part becausesea level was lower. Higher water levelsin the bay allow water to be pushed far-ther inland, causing greater floodingdamage, and also increase the strength ofwaves. In relatively shallow ChesapeakeBay, a 1-foot increase in water level pro-duces a 40 percent increase in wavepower.28

Projected Future Impacts ofGlobal WarmingThe impacts of global warming are ex-pected to increase in scope and severityin coming years, unless we find a way toquickly reduce our emissions of globalwarming pollutants.

Global ImpactsMany scientists and policy-makers (suchas the European Union) recognize a 2˚Celsius (3.6˚ Fahrenheit) increase in glo-bal average temperatures over pre-indus-trial levels as a rough limit beyond whichlarge-scale, dangerous impacts of globalwarming would become unavoidable.29

Even below 2˚ C, significant impacts fromglobal warming are likely, such as dam-age to many ecosystems, decreases in cropyields, sea level rise, and the widespreadloss of coral reefs.30

Beyond 2˚ C, however, the impacts ofglobal warming become much more se-vere, including some or all of the follow-ing impacts:

• Eventual loss of the Greenland icesheet, triggering a sea-level rise of 7meters over the next millennium(and possibly much faster).31

• A further increase in the intensity ofhurricanes.

• Loss of 97 percent of the world’scoral reefs.

• Displacement of tens of millions ofpeople due to sea level rise.

• Total loss of Arctic summer sea ice.

• Expansion of insect-borne disease.

• Greater risk of positive feedbackeffects – such as the release ofmethane stored in permafrost – thatcould lead to even greater warmingin the future.32

At temperature increases of 3 to 4˚ C,far more dramatic shifts would take place,including:

• Increased potential for shutdown ofthe thermohaline circulation, whichcarries warmth from the tropics toEurope.


• Increased potential for melting of theWest Antarctic ice sheet, which initself could lead to a 5 to 6 meter risein sea level.

• Major crop failures in many parts ofthe world.

• Extreme disruptions to ecosystems.33

In addition, the more global tempera-tures rise, the greater the risk that climatechange is abrupt and unpredictable. Thehistorical climate record includes manyinstances in which the world’s climateshifted dramatically in the course of de-cades, even years—with local temperaturechanges of as much as 10˚ C in 10 years.34

Should the world continue on its cur-rent course, with fossil fuel consumptioncontinuing to rise, temperature increasesof well above 2˚ C are likely to occur. TheIntergovernmental Panel on ClimateChange, in its 2001 Third AssessmentReport, laid out a scenario in which popu-lation, economic output and fossil fuelconsumption continue to grow dramati-cally. Under that scenario, the concen-tration of carbon dioxide in theatmosphere in 2100 would be nearlythree-and-a-half times its preindustriallevel, global average temperatures by theend of the century would be 4.5˚ C higherthan in 1990, and temperatures wouldcontinue to rise for generations to come.35

Maryland ImpactsGlobal warming will have consequencesfor both rural and urban areas in Maryland.

Maryland’s climate is expected to growwarmer, with spring temperatures risingby 1° F to 7° F by 2100.36 Other seasonswould be warmer, with average tempera-tures 2 to 9° F higher. Precipitation isprojected to increase by an average of 20percent. The increase would be concen-trated in the winter and would likely re-sult in more extremely wet or snowy days.

Rising Sea LevelBy 2100, ocean level is expected to be an-other 19 inches higher.37 Statewide, anestimated 380,000 acres of land are lessthan five feet above sea level and are vul-nerable to inundation during high tidesor to complete submersion.38 Wicomico,Somerset and Dorchester counties aremost at risk. By one estimate, shorelinesin those counties could migrate inland bythree to six miles.39

As sea level rises, beaches and wetlandsare the first areas to be claimed by theocean. Along undeveloped shoreline,wetlands migrate inland and new beachesform. In Maryland, however, develop-ment prevents this regeneration. Muchland along the bay and ocean has beendeveloped, leaving no room for new wet-lands and beaches and causing the stateto lose valuable wildlife habitat and rec-reation areas. Development just inlandfrom current wetlands and beaches oftenis protected by storm walls, preventingthe evolution of new coastal wetlandsthrough the inundation of low-lying land.From 1978 to 1998, Maryland landown-ers constructed more than 300 miles ofseawalls and other barriers against risingocean levels, meaning that wetlands onthe ocean side of those barriers will notbe able to migrate inland.40

Before the ocean overtakes coastalland, salt water seeps into the freshwaterbelow it, penetrating aquifers and drink-ing-water wells. Water no longer can beused for drinking or irrigating. Risingwater levels can also impair the functionof septic systems, making it very difficultto sell affected homes.41

Declining Water QualityGlobal warming may trigger a decline inwater quality in the Chesapeake Bay,harming fish and crab populations. In-creased precipitation in the bay’s water-shed will boost stream flows and theamount of nutrients that run off into the


bay. Excess nutrients promote algalblooms, which can deplete oxygen levelsbelow those needed by aquatic animals.Already, nutrient pollution causes algalblooms and areas of oxygen depletioncovering more than one-third of the bayeach summer.42 The problem will growworse as water temperatures rise, becausewarmer water cannot retain oxygen aseasily.

Increased precipitation would changethe bay’s salinity, which can affect themigratory patterns of fish and crabs. Toomuch freshwater in the bay can kill oys-ters. On the other hand, sea level risecould instead make the bay saltier—un-der these conditions, oyster diseases mayspread more readily.43

Increasing water temperatures in thebay and its tributaries will also have det-rimental effects. Late last summer, highwater temperatures were blamed for thewidespread die-off of eelgrass in themiddle and lower parts of the bay. Sus-tained temperature increases could dev-astate this critical habitat and affect thejuvenile crabs and finfish that use it forshelter.44

Loss of Plant and Animal SpeciesHigher temperatures and changes in pre-cipitation will alter the mix of plants andanimals that can survive in Maryland.Forested areas may shrink or become lessdense. Hardwood trees could migratenorth and be replaced by southern pinesand oaks. Insect populations may thriveas temperatures increase.

As plant types change, birds and otheranimals may have to move northward tofind suitable habitat. By one estimate, 34species of birds that currently spend atleast part of the year in Maryland may beforced out of the state by a changing cli-mate, including the Baltimore Oriole, thestate bird.45

The loss of wetlands and decliningwater quality in the Chesapeake Bay will

harm waterfowl. Wetlands provide habi-tat for resident, migrating and winteringbirds, such as Northern pintail ducks,osprey, snowy egrets, and redhead ducks,and the loss of wetlands to rising sea levelmay cause a decline in bird populations.46

Food supplies may dwindle as algalblooms, increased water temperature, anddepleted oxygen levels impair the growthof the aquatic plants and animals that arean important food source for many wa-terfowl.47

Changing plant and animal popula-tions will have an economic impact onthe state. In 2001, people who hunted,fished, or watched wildlife in Marylandspent $1.7 billion in the state’s economy,supporting nearly 25,000 jobs.48 Smallerwildlife populations may decrease thestate’s attractiveness as a destination forpeople seeking an outdoor experience.

Threats to Public HealthHigher temperatures will increaseweather-related illnesses and fatalities.The number of heat-related deaths inMaryland could increase by 50 percentduring summer heat waves.49 Air qualitycould decline as hot summer days facili-tate the formation of smog, ground-levelpollution that can inflict respiratory dam-age. Smog levels in Maryland are alreadyhigh enough to cause health problemsand could increase further as tempera-tures rise.50

The incidence of insect-borne diseasemay rise also, as mosquito and tick popu-lations thrive in warm, wet weather.51

Mosquitoes in Maryland have alreadybeen found to carry West Nile virus,malaria, dengue fever and St. Louis en-cephalitis. Ticks may transmit Lyme disease.

Declining Agricultural ProductionHigher temperatures and increased pre-cipitation would affect Maryland’s $1.3billion agricultural industry. The state’sprimary crops are corn, hay, soybeans and


wheat. Higher temperatures would de-crease corn and hay production, while soy-bean and wheat production could rise orfall, depending on precipitation changes.52

Human Activities AreCausing Global WarmingMany of the changes described above areconsistent with the kinds of climatic shiftsscientists believe will occur as a result ofglobal warming. They are also signs thathuman activities have begun to affect theclimate through the release of pollutants(known as greenhouse gases or globalwarming pollutants) that exacerbate theearth’s natural greenhouse effect.

The Greenhouse EffectGlobal warming is caused by human ex-acerbation of the greenhouse effect. Thegreenhouse effect is a natural phenom-

enon in which gases in the earth’s atmo-sphere, including water vapor and carbondioxide, trap radiation from the sun nearthe planet’s surface. The greenhouse ef-fect is necessary for the survival of life;without it, temperatures on earth wouldbe too cold for humans and other lifeforms to survive.

But human activities, particularly overthe last century, have altered the compo-sition of the atmosphere in ways that in-tensify the greenhouse effect.

Since 1750, for example, the concen-tration of carbon dioxide (the leading glo-bal warming pollutant) in the atmospherehas increased by 35 percent as a result ofhuman activity.53 (See Figure 2.) The cur-rent rate of increase in carbon dioxideconcentration is unprecedented in the last20,000 years.54 Figure 2 shows increasesin carbon dioxide concentrations for thepast 45 years. Concentrations of otherglobal warming pollutants have increasedas well.

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Global Warming Pollution inMarylandCarbon dioxide emitted from fossil fueluse is the leading cause of global warm-ing. In 2004, fossil fuel use in Marylandresulted in the release of 77.4 millionmetric tons of carbon dioxide (MMTCO2,see note on units next page).

The transportation sector is respon-sible for approximately 37 percent ofMaryland’s releases of carbon dioxide.56

(See Figure 3.) Cars and light trucks—such as pickups, minivans and SUVs—are the most important sources of global

Figure 3. Maryland Sources ofGlobal Warming Emissions in 200458

Other Global Warming Pollutants

This report focuses on transportation-related emissions of carbon dioxide—the leading pollutant responsible for global warming and the global warm-ing gas released in the largest quantities by cars and trucks. Cars and trucks

produce other global warming pollution, however, that must be considered inany emission reduction strategy.

• Methane – Methane gas is likely the second most important contributor toglobal warming. Cars and light trucks produce methane in their exhaust, butit is thought that they are only minor emitters of methane and that pollutionwill be reduced in the future through improved emission control systems.59

• Nitrous Oxide – Nitrous oxide is also produced in automobile exhaust, withmobile sources estimated to contribute about 13 percent of U.S. nitrousoxide emissions in 2002.60 As with methane emissions, improved pollutioncontrol measures may reduce nitrous oxide emissions in the future.

• Hydrofluorocarbons (HFCs) – HFCs are extremely potent global warminggases, yet tend to be released in only very small quantities. HFCs are oftenused as coolants in vehicle air conditioning systems and can escape fromthose systems into the environment.

• Black carbon – Black carbon, otherwise known as “soot,” is a product of theburning of fossil fuels, including diesel fuel used in heavy-duty trucks and asmall percentage of light-duty vehicles. Recent research has suggested that,because black carbon absorbs sunlight in the atmosphere and on snow andicepack, it may be a major contributor to global warming, perhaps second inimportance only to carbon dioxide. Research is continuing on the degree towhich black carbon pollution contributes to global warming.61


warming pollution within the transpor-tation sector, responsible for approxi-mately 70 percent of all transportation-sector emissions and more than one-quarter of Maryland’s total emissions ofglobal warming pollution.57

Pollution Reduction Effortsin MarylandMaryland has already taken several stepsto begin reducing its global warmingemissions. In 2004, the state adopted ef-ficiency standards for nine common resi-dential and commercial appliances,standards that were later adopted at thefederal level.62 That same year, Marylandenacted a requirement that 7.5 percentof the state’s electricity come from cleanrenewable resources by 2019.63 Both ofthese measures should reduce the amountof carbon-intensive electricity consumedin the state. Maryland joined the RegionalGreenhouse Gas Initiative (RGGI) ear-lier this year, an agreement among eightnortheastern states to reduce globalwarming pollution from power plants by10 percent by 2018. The full details of

the agreement have not yet been estab-lished. Actual savings will depend onhow strongly the state implements theprogram.

While these standards will help to re-duce Maryland’s global warming pollu-tion, they touch only some of the sectorsthat produce global warming emissions.One of the major sectors not covered istransportation. Maryland will need to domore to reduce emissions from thosesectors, as well as begin to address thechallenge of emissions from the transpor-tation sector.

The TransportationChallengeThe challenge of reducing global warm-ing pollution from cars and trucks is for-midable, and growing increasingly sowith each passing year.

Three trends in the transportation sec-tor—increasing vehicle miles traveled,stagnating fuel economy, and increasingnumbers of light trucks and SUVs—makethe challenge of reducing global warm-ing pollution in Maryland even greater.

A Note on Units

Because various gases contribute to global warming, and the potency of thewarming effects of those gases varies, inventories of global warming pollu-tion typically use units that communicate emissions in terms of their global

warming potential.In this report, we are measuring emissions of carbon dioxide only and thus

report emissions in terms of carbon dioxide. Other documents may communicatepollution in terms of “carbon equivalent.” To translate carbon equivalent to car-bon dioxide, one can simply multiply by 3.66.


Increasing Vehicle Miles TraveledMaryland residents are traveling moremiles in their cars and light trucks thanever before. Between 1995 and 2005, thenumber of vehicle-miles traveled (VMT)annually on Maryland’s roads increasedfrom 44.9 billion miles to 56.7 billionmiles—an increase of 26 percent.64 (SeeFigure 4.) If VMT growth continues atthe same rate, by 2020, VMT will in-crease 41 percent to 79.8 billion miles.Given the population increase that willaccompany the recent reassignment ofmilitary personnel from other states toMaryland, this increase in VMT is likelyto be a low-end estimate of business-as-usual projections.

Stagnating Fuel EconomyThe imposition of federal Corporate Av-erage Fuel Economy (CAFE) standardsbeginning in 1975 led to dramatic im-provements in the fuel efficiency ofAmerican cars and light-duty trucks. TheCAFE standards required a gradual in-crease in fuel economy during the 1970sand 1980s, topping out at an average fueleconomy for new cars of 27.5 miles per

gallon (mpg) by 1990 and 20.7 mpg forlight trucks by 1996.66 (The NationalHighway Traffic Safety Administrationhas begun to phase in an increase in thelight truck standard to 22.2 mpg, to befully achieved by model year 2007.)

In the decade-and-a-half followingenactment of the CAFE standards, the“real world”67 fuel economy of passen-ger cars nearly doubled—from 13.4 mpgin 1975 to 24.0 mpg in 1988. Similarly,light trucks experienced an increase inreal-world fuel economy from 11.8 mpgin 1975 to 18.3 mpg in 1987.68

However, the trend in the 1990s wastoward less fuel-efficient vehicles.Though fuel economy has stabilized forthe past several years, in many casesAmericans get fewer miles per gallonfrom their new vehicles today than theydid during the Reagan administration.

Until recently, the federal governmenthad failed to increase CAFE standards formore than a decade. To make mattersworse, changes in driving patterns, in-cluding higher speeds and increased ur-ban driving, have led to a real-worlddecrease in fuel economy. An EPA analy-sis of fuel economy trends found that the

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average real-world fuel economy of light-duty vehicles sold in 2003 was lower thanthe average fuel economy of vehicles soldin 1981. Indeed, the average real-worldfuel economy of new cars and light trucksactually declined by 7 percent between1988 and 2003.69 (See Figure 5.) Com-bined average real-world fuel economystarted at 13 mpg in 1975, rose to 21.8 in1988, and then dropped to 20.3 in 2003.

Amid growing public pressure to im-prove vehicle fuel economy, the U.S. De-partment of Transportation is increasingCAFE standards for light trucks by amodest 1.5 mpg between 2005 and 2007.While this action does not go far enoughto take advantage of many technologiesthat could cost-effectively improve fueleconomy, even a modest increase inCAFE standards has some effect in re-ducing the rate of growth of transporta-tion carbon dioxide pollution.

Growing Numbers of SUVs andLight TrucksWhile the fuel economy of the averagecar and light truck has stagnated over thepast two decades, the average fueleconomy of the entire new-car fleet has

declined—thanks to the dramatic shifttoward sport utility vehicles (SUVs), vansand light trucks.

In 1975, when the first federal CAFEstandards were enacted, SUVs made up2 percent of the light-duty vehicle mar-ket, vans 5 percent, and pickup trucks 13percent. By model year 2004, however,SUVs accounted for 26 percent of light-duty vehicle sales, vans 7 percent, andpickup trucks 15 percent. The light-dutymarket share of passenger cars and sta-tion wagons dropped over the same pe-riod from 81 percent to 52 percent.71 (SeeFigure 6.)

This shift toward larger vehicles hascaused the average fuel economy of theentire new light-duty vehicle fleet to dipas low as 20.4 mpg in 2001—lower thanat any time since 1980 and down by nearly8 percent from the historical peak in 1987and 1988.72

The trend toward SUVs and lighttrucks could continue, with light trucksmaking up an increasing percentage ofthe entire light-duty fleet as time goes on.The Environmental Protection Agencyprojects that by 2020, 64 percent of alllight-duty vehicles on the road will belight trucks.73 Recent increases in gasoline

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Combined Real WorldMileageTruck - CAFE Standard

Truck - Real World Mileage

Figure 5. Average Fuel Economy for New Light-Duty Vehicle Fleet on theDecline70

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prices have slowed sales of SUVs, but itis too early to determine if the long-termshift toward SUVs and light trucks willchange significantly.

Recently, manufacturers have pro-moted “cross-over” vehicles as an alter-native to SUVs. These are vehicles thatlook like large station wagons but are cat-egorized as SUVs. Because cross-overvehicles are subject to light truck emis-sion standards, their fuel economy is oftenno better than that of conventional SUVs.

The combination of these three fac-tors—more miles traveled, increasinglyin trucks and SUVs, with stagnant fueleconomy across the entire vehicle fleet—poses a great challenge to Marylandpolicy-makers as they attempt to reduceglobal warming pollution from the trans-portation sector.

Vehicle Carbon DioxidePollution in Maryland: Pastand ProjectedBased on Maryland-specific fuel con-sumption data compiled by the U.S.Energy Information Administration

(EIA), cars and light-duty trucks releasedapproximately 16.5 million metric tonsof carbon dioxide into the atmosphere in1990. By 2004, those emissions had in-creased by 32 percent, to 21.7 MMTCO2,and cars and trucks were responsible for28 percent of Maryland’s emissions ofglobal warming pollution.

Any attempt to project Maryland’s fu-ture global warming pollution dependsgreatly on the assumptions used. The“Assumptions and Methodology” sectionat the conclusion of this report describesin detail the assumptions used to developthe following projections. Simply put, the“base case” for carbon dioxide emissions(based largely on data and projections bystate and federal government agencies)assumes continued growth in vehicletravel, slight improvement in vehicle fueleconomy, and a continuation of the trendtoward increased purchases of sport util-ity vehicles and other light trucks.

Based on these assumptions, carbondioxide emissions from the Marylandlight-duty vehicle fleet are projected toincrease 12 percent over 2004 levels by2010, followed by a further 20 percentincrease between 2010 and 2020. In otherwords, by 2020, carbon dioxide emissionsfrom cars and light trucks could be 78

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Figure 6. Light-Duty Vehicle Mix Shifts from Cars to Trucks, Vans and SUVsPe

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Transportation and Global Warming: A Primer

A gallon of gasoline contains a set amount of carbon, nearly all of whichis released to the atmosphere when it is burned. Some of the carbon is

released in the form of hydrocarbons; most of it is released in the form ofcarbon dioxide. For each gallon of gasoline burned in a vehicle, about 19.6pounds of carbon dioxide is released to the atmosphere. In addition, the con-sumption of gasoline creates significant additional “upstream” emissions ofcarbon dioxide resulting from the extraction, transportation, refining anddistribution of the fuel. Other fuels have greater or smaller amounts of car-bon in a gallon (or its equivalent).

Unlike other vehicular air pollutants that result from the incomplete com-bustion of fossil fuels or from fuel impurities, carbon dioxide is a naturalresult of the combustion process. As a result, there are three main ways tolimit carbon dioxide pollution from motor vehicles:

1. Drive more efficient vehicles.

2. Reduce the number of miles traveled.

3. Switch to fuels with a lower carbon content, such as biofuels containingethanol.

Vehicles also emit smaller amounts of other global warming gases, such asmethane and nitrous oxide, as well as hydrofluorocarbons from the use of theair conditioning system. Control of some of these emissions is possible throughmeans other than reducing fuel use or substituting low-carbon fuels.

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Figure 7. Actual and Projected Carbon Dioxide Emissions from Light-DutyVehicles in Maryland, 1990-2020


percent greater than 1990 levels in theabsence of action to reduce emissions.(See Figure 7.)

An increase of such magnitude wouldseverely challenge Maryland’s ability tostabilize and eventually reduce globalwarming pollution from the transporta-tion sector and the state as a whole.Should these increases in emissions fromcars and light trucks occur, Marylandwould need to achieve dramatic reduc-tions in global warming pollution fromother sectors of the state’s economy inorder to achieve long-term reductions of

70 to 85 percent, a level of reduction es-timated by scientists as necessary to limitany dangerous threat to the climate.74

However, this path toward increasingcarbon dioxide pollution from cars andlight trucks is not inevitable. Public poli-cies that require or encourage the pur-chase of more fuel-efficient or advancedtechnology cars can make a significantdent in Maryland’s future emissions of glo-bal warming pollution while potentiallysaving money for drivers. One of the mostpowerful policy options is setting limitson vehicle global warming pollution.


M aryland has many potential toolsavailable to reduce emissions ofglobal warming pollution from

the transportation sector. In addition togreater efforts to promote alternatives todriving, the state should use one of themost powerful tools it has available: glo-bal warming pollution standards for carsand trucks.

The Clean Air Act gives states twooptions for control of motor vehicle emis-sions identified as pollutants under theAct. States may choose to comply withfederal emission standards or adopt themore protective standards—known as theClean Cars Program—developed by thestate of California, the only state empow-ered by the Clean Air Act to devise itsown emission regulations.

Ten states—New Jersey, New York,Massachusetts, Connecticut, Rhode Is-land, Vermont, Maine, Oregon, Wash-ington and California—have adopted theClean Cars Program, including the ve-hicle global warming emission standards.Several other states are actively consid-ering it.

As discussed below, adoption of theClean Cars Program would significantly

reduce emissions of global warming gasesfrom cars and trucks, providing impor-tant assistance in Maryland’s efforts tocurb global warming pollution.

The Clean Cars Program has twoparts, analyzed separately below. The firstcomponent of the Clean Cars Program,the Low-Emission Vehicle II (LEV II)standards, promotes advanced-technol-ogy vehicles and would provide a first stepin reducing greenhouse gas pollution.The second part of the program targetsglobal warming pollution directly.

LEV II StandardsThe LEV II standards seek to reduceemissions of smog-forming and otherhazardous pollutants. They achieve thisby establishing fleet-wide limits ontailpipe emissions and by requiring thesale of advanced-technology vehicles suchas hybrids that have even lower emissions.

By adopting the program, Marylandcan expect to have increasing percentagesof advanced-technology vehicles on theroad over the next decade and more.

Tools to Reduce Global WarmingPollution from Cars and Light Trucks

Tools to Reduce Global Warming Pollution 23

Some of the technological changes en-couraged by LEV II will reduce emissionsof global warming pollutants. LEV IIpromotes advanced technology vehiclesin three ways, as described below.

Pure Zero-Emission Vehicles“Pure” zero-emission vehicles (pureZEVs) are those—like battery-electricand fuel-cell vehicles—that release notoxic or smog-forming pollutants fromtheir tailpipes or fuel systems. They alsohave the potential to release far fewer glo-bal warming gases than today’s vehicles.(Note, however, that fuel-cell vehicleshave zero emissions only when the elec-tricity used to create the hydrogen is gen-erated from renewable sources.)

The most recent revision to LEV II’sadvanced technology program shifted theemphasis from near-term deployment ofbattery-electric vehicles to the long-termdevelopment of hydrogen fuel-cell ve-hicles. As a result, automakers will nothave to sell fuel-cell or other pure zero-emission vehicles in Maryland until atleast model year 2012. Even then, thenumber of pure ZEVs required for salein Maryland would be small, represent-ing less than one percent of new car andlight truck sales until model year 2016.75

In addition, the California Air Re-sources Board (CARB), which adminis-ters the program in California, hasconvened a panel of experts to review thestatus of fuel-cell technology prior to theagency enforcing any pure ZEV require-ments for the 2009 model year and be-yond.76 After reviewing the panel’sconclusion, CARB staff may make a rec-ommendation to modify the advancedtechnology program’s requirements forpure ZEVs, particularly if it seems thatZEVs are not yet ready for widespreadcommercial release. Every revisionCARB has made to the program in thepast has been to increase flexibility forautomakers.

The current LEV II standard, there-fore, requires the sale of very few purezero-emission vehicles over the next de-cade. But it does provide an incentive forautomakers to continue research and de-velopment work on technologies such ashydrogen fuel-cell vehicles that couldprovide zero-emission transportation inthe future.

Partial Zero-Emission Vehicle(PZEV) CreditsThe majority of vehicles that automakersproduce to comply with the advancedtechnology program will be vehicles thatreceive “partial ZEV credit”—otherwiseknown as “PZEVs.” PZEVs are conven-tional gasoline vehicles in every way butone: they are engineered to produce dra-matically lower emissions of air toxics andsmog-forming pollutants.

While PZEVs will play an importantrole in helping Maryland to achieve itsair quality goals, the technologies usedin PZEVs do not necessarily make a sub-stantial contribution to reducing globalwarming pollution from cars. Thus, wedo not assume any global warming ben-efits from the PZEV portion of the program.

Advanced Technology PZEVs(AT-PZEVs)The greatest near-term global warmingimpact of the advanced technology pro-gram will likely come from provisions toencourage the sale of PZEVs that eitherrun on a cleaner alternative fuel, such ascompressed natural gas, or that use ad-vanced technologies, such as hybrid-elec-tric drive. These are known as “advancedtechnology PZEVs” or “AT-PZEVs.”

To encourage automakers to releaseadditional new hybrid vehicles as early aspossible, automakers are allowed to com-ply with part of their sales obligations inthe early years of the program throughthe sale of AT-PZEVs. Automakers haveflexibility on how much they want to use


this compliance path. The most likelyscenario would result in hybrids consti-tuting six percent of new car sales in 2010,increasing to ten percent by 2014.

Hybrid-electric vehicles are the mostlikely technology to be used to complywith AT-PZEV standards. Hybrids haveproven to be very popular with consumers,especially in an era of higher and rapidlyfluctuating gasoline prices. Sales of hy-brid vehicles have increased steadily sincetheir introduction to the domestic mar-ket in December 1999. About 212,000hybrids were sold in the U.S. in 2005, a250 percent increase over sales in 2004.77

Thus far, seven models of vehicles havebeen certified to AT-PZEV emissionstandards: the Toyota Prius, the HondaCivic hybrid and Accord hybrid, the FordEscape hybrid, the Mercury Mariner hy-brid, the Mazda Tribute hybrid, and thenatural gas-powered Honda Civic GX.78

(Several other hybrid vehicles, such as theToyota Camry, are on the market but ei-ther their emissions are too high to meetAT-PZEV standards or the automakerdoes not want to offer the extended war-ranty required with PZEVs. These ve-hicles nonetheless can achieve measurablereductions in global warming emissions.)

Unfortunately, although a healthymarket for hybrids appears to exist,

automakers have not yet supplied hybridsin large enough quantities to meet con-sumer demand. The demand crunchcould ease slightly if automakers intro-duce additional hybrid models asplanned—including hybrid versions ofthe Nissan Altima and Toyota Sienna—that could qualify for AT-PZEV credit.79

The planned increase in hybrid modelscomes largely as a strategy to comply withstandards in states that have adopted theClean Cars Program. Future availabilityof these hybrids in other states is highlyuncertain.

Should automakers choose to maxi-mize their use of AT-PZEVs to complywith the advanced technology programin Maryland—and do so using vehiclessimilar to the Toyota Prius—hybridscould make up about 6.3 percent of thestate’s car and light truck sales in 2010,increasing to 10.1 percent by 2014. (SeeFigure 8.) This translates to sales of about20,000 hybrids in Maryland in 2010, in-creasing to approximately 31,000 annu-ally by 2016. Because the advancedtechnology program offers a great dealof flexibility, however, automakers couldchoose to comply by manufacturinggreater numbers of less-advanced hybridsor smaller numbers of pure ZEVs, amongother options.

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Figure 8. Percentage of Light-Duty Vehicle Sales in Maryland with Adoptionof Clean Cars Program, 2010 through 2020

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Also unclear is the degree of globalwarming gas reductions that can be ex-pected from vehicles complying withAT-PZEV standards. Hybrid-electric ve-hicles and alternative-fuel vehicles varygreatly in their emissions of global warm-ing pollution. Some, like the ToyotaPrius, offer great reductions in globalwarming emissions. Others, such as hy-brid pickup trucks to be sold by GeneralMotors and DaimlerChrysler, continueto have significant global warming pol-lution despite their improved emissionscompared to conventional models. TheLEV II program does provide additionalcredit to hybrid-electric vehicles that at-tain a greater share of their power froman electric motor, which generally allowsthem to achieve lower carbon dioxideemissions. For the purposes of this analy-sis, we assume that hybrids manufacturedto comply with AT-PZEV standards willrelease about 30 percent fewer globalwarming gases per mile than conventionalvehicles.80

LEV II Program Impacts: Long TermOn the front end, no assessment of short-term global warming pollution reductionscan precisely capture the potential long-term and indirect benefits of the LEV IIprogram in reducing carbon dioxideemissions. At its heart, the program is a“technology forcing” program—one thatattempts to jump-start advanced technol-ogy vehicle development and the adop-tion of these technologies in themainstream auto market. That being said,however, adoption of the program willlikely bring about significant long-termpollution reductions as technologicalchanges brought about by the programspread to other vehicles in the Marylandcar and truck fleet.

An example of the potential power ofthe program to hasten technologicalchange is the development of hybrid

vehicles in the 1990s. Adoption of theoriginal LEV program sparked public andprivate-sector research efforts into thedevelopment of advanced batteries andelectric-drive technologies. While thegeneration of full-function electric ve-hicles that resulted from that research—such as Honda’s EV-Plus and GeneralMotors’s EV1—were not sold in largequantities, the research effort drove ad-vances in electric vehicle technology thatfacilitated the birth of the popular hybrid-electric systems that now power hundredsof thousands of vehicles worldwide andhave laid the groundwork for recent ad-vances in fuel-cell vehicle technology.81

Similarly, the current form of the LEVII program is designed to encourage con-tinued investment in hybrid-electric andhydrogen fuel-cell vehicle developmentand may lead to the development of newtypes of vehicles (such as “plug-in hy-brids” that combine the benefits of bat-tery-electric and hybrid-electric vehicles)with significant benefits for the climate.Once developed and offered to consum-ers, it is possible that these vehicles couldcome to represent a far greater share ofthe new car market than is estimated here.

LEV II Program Impacts: Short TermThe short-term impact of the LEV IIprogram on carbon dioxide emissions inMaryland will largely be determined byhow automakers choose to comply withthe program’s flexible provisions. Thereare almost infinite options available toautomakers for compliance—however, itis likely that one or several technologieswill dominate the mix of vehicles certi-fied under the program.

We assume that automakers will takemaximum advantage of the ability to meetZEV requirements with PZEVs and AT-PZEVs. We also assume that vehicles soldto meet AT-PZEV requirements are hy-brid-electric vehicles with technological


characteristics similar to the Toyota Prius.We assume that any vehicles sold to meetpure ZEV requirements are hydrogenfuel-cell vehicles whose fuel is generatedfrom natural gas. And we use conserva-tive assumptions about the carbon diox-ide emission reductions that could resultfrom hybrid or fuel-cell vehicles.

Vehicle Global WarmingPollution StandardsIn July 2002, California adopted the firstlaw to control carbon dioxide emissionsfrom automobiles. Beginning in modelyear 2009, automakers will have to ad-here to fleet average emission limits forcarbon dioxide similar to current limitson smog-forming and other pollutants.Emissions of global warming pollutionwill fall and consumers will save money.

The standards require CARB to pro-pose limits that “achieve the maximumfeasible and cost effective reduction ofgreenhouse gas emissions from motorvehicles.” Limits on vehicle travel, newgasoline or vehicle taxes, or limitationson ownership of SUVs or other lighttrucks cannot be imposed to attain thenew standards.82 In September 2004,CARB adopted rules for implementation

of the global warming pollution stan-dards. Those proposed rules provided thebasis of our analysis here.

In developing the global warming pol-lution standards, the CARB staff reviewedseveral analyses of the types of technolo-gies that could be used to achieve “maxi-mum feasible and cost effective”reductions in global warming pollutionfrom vehicles. CARB’s proposal estimatesthat near-term technologies could reduceaverage global warming pollution fromcars and the lightest light trucks by 25percent and from heavier light trucks by18 percent. Over the medium term (2013to 2016), cost-effective reductions of 34percent for cars and smaller light trucksand 25 percent for heavier light trucksare feasible.83

One of the central requirements of thestandards is that they be cost-effective.CARB has adhered to that requirementand added a margin of error to ensure thatthe standards meet that requirement.Early analysis by CARB suggested thatdeeper cuts in vehicle emissions could bemade more quickly than were ultimatelyincorporated into the standard. CARB’sinitial draft proposal for implementationof the standards called for cost-effectiveemission reductions of 22 percent fromcars and 24 percent from light trucks inthe near term. Over the medium term(2012 to 2014), cost-effective reductionsof 32 percent for cars and 30 percent forlight-trucks were deemed feasible. In ad-dition, the standards were assumed to bephased in much more quickly than un-der CARB’s most recent proposal.84

The technological changes needed toachieve the reductions that CARB didrequire (such as five and six-speed auto-matic transmissions and improved elec-trical systems) will likely result in modestincreases in vehicle costs that would bemore than recouped over time by con-sumers in the form of reduced fuel ex-penses. CARB projects that cars and the

With the Clean Cars Program, a

consumer who buys a new car in

2016 would save $20 per month

due to lower operating expenses

despite higher loan costs.


lightest light trucks attaining the 34 percentreduction in global warming pollutionrequired by 2016 would cost an averageof $1,064 more for consumers, whileheavier light trucks achieving the re-quired 25 percent reduction would costabout $1,029 more.85

However, the agency also estimatesthat the rules will significantly reduceoperating costs for new vehicles. Thoughconsumers will face higher monthly loanpayments when purchasing vehicles thatcomply with the standards, those in-creased costs will be more than offset bylower operating expenses.

For example, a consumer who buys a

new car in 2016 will save $20 per monthdue to lower operating expenses despitehigher loan costs, assuming a gas price ofthree dollars per gallon. After the loan ispaid off, the consumer will save $41 permonth. Drivers who purchase a lighttruck or who pay for the vehicle in cashwill experience greater savings. Even atlower gas prices, consumers save moneyfrom day one and the accumulated sav-ings exceed the increased purchase pricein only a few years.86 (See Table 1.)

CARB also projects that the net im-pact of the standards to the state’s economywill be positive, suggesting that Marylandas a whole could save money while at the

Car SUV Car SUV

Annual Net Savings while Repaying Loan $245 $320 $115 $170

Annual Net Savings after Loan Is Repaid $490 $560 $360 $410

Time to Recoup Higher Cost of Vehicle 2.2 years 2.5 years 2.9 years 3.4 years

Gas Price of$3 per Gallon

Gas Price of$2.20 per Gallon

Table 1. Net Savings for a Consumer Under Global Warming PollutionStandards in 201688

Figure 9. Reductions in Carbon Dioxide Emissions Under Global WarmingPollution Standards (Light-Duty Vehicles)

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same time reducing the state’s overallemissions of global warming gases.87

Assuming that Maryland adopts thestandards beginning with the 2011 model

The emission standards would

reduce carbon dioxide emissions from

light-duty vehicles by 14.1 percent

in 2020—a reduction of

4.4 million tons per year from

business-as-usual projections.

year, the resulting reductions in globalwarming pollution would be significant.Compared to the base case projection, theemission standards would reduce light-duty carbon dioxide emissions by 14.1percent by 2020—for a total reduction of4.4 MMTCO2. (See Figure 9.)

Adopting the Clean Cars Program cancontribute significantly to efforts to reduceglobal warming pollution fromMaryland’s transportation sector. Withboth components in effect, emissionsfrom light-duty cars and trucks would be16 percent greater in 2020 than they werein 2004, compared to 35 percent greaterif no action is taken. From 2010 to 2020,adoption of the Clean Cars Program willlimit the increase in emission from carsand light trucks to just 3 percent.

Policy Recommendations 29

A ttaining reductions in carbon di-oxide emissions will require signifi-cant actions to reduce emissions

from light-duty vehicles. No one policywill solve the problem. The Clean CarsProgram is the best single policy, andcomes at a net financial gain to the state,but Maryland will need to pursue a rangeof policies.

Reduce Per-Mile Emissionsfrom Vehicles

Adopt the Clean Cars ProgramThe first step Maryland should take is toadopt the Clean Cars Program for imple-mentation in model year 2011, establish-ing vehicle global warming pollutionstandards. The standards will greatly re-duce emissions from light-duty vehiclesfrom projected levels. The analysisthroughout this report testifies to theimportance of the Clean Cars Program.

Encourage the Purchase of Lower-Carbon VehiclesThe state should create incentives forindividuals and fleets to purchase vehicleswith lower carbon emissions. One pos-sible approach is to offer incentives thatwould give a rebate to car buyers whopurchase vehicles that emit less globalwarming pollution. In addition to hybridcars, any vehicle that offers below-aver-age global warming emissions potentiallycould qualify (provided that emissions ofother pollutants, such as diesel particu-late matter, do not contribute to air qual-ity problems). The rebate could befunded by a fee on purchasers of less effi-cient vehicles and thus could be revenueneutral for the state. Connecticut andseveral other New England states areconsidering such a program.89

Another option would be to offer astate tax credit for the purchase of hy-brids that meet standards for low emis-sions of global warming pollution.

State and local governments shouldpurchase lower carbon emission vehiclesfor their fleets. This could be accomplished

Policy Recommendations


by buying vehicles that have the lowestemissions in their class and by purchas-ing the lowest-emitting vehicle that cansatisfy the intended purpose.

Promote BiofuelsBiofuels are typically made from suchcrops as corn, soybeans, canola, rapeseed,or mustard seed. The global warmingimpact of biofuels can be much lowerthan petroleum fuels, especially if they arecreated from specialized energy cropssuch as switchgrass. Crops temporarilyremove carbon from the atmosphere asthey grow and return it when they decayor are burned.90 Burning fossil fuels releasescarbon that had been removed from theatmosphere thousands of years ago.

Renewable fuels typically are mixedwith petroleum-based fuels, such as gaso-line or diesel. All vehicles are capable ofusing fuel with a small percentage ofbiofuel. Vehicles can be configured to runon higher percentages of biofuel and thusprovide greater global warming pollutionadvantages. A statewide renewable fuelstandard can be structured either to re-quire some amount of renewable fuel inall vehicle fuel sold in Maryland, or torequire that a percentage of all fuel soldin the state consist of renewable content.Maryland could begin with a requirementthat 10 percent of gasoline consist of etha-nol and that 5 percent of diesel fuel con-sist of biodiesel. The state shouldpromote fuels that provide the greatestglobal warming benefit and that will notadversely affect air quality or the envi-ronment.

A number of other states have success-fully implemented similar renewable fu-els standards. Minnesota recently beganto require that all diesel contain at least 2percent biodiesel, and many states—suchas California, Colorado, New York, Iowaand several other Midwestern states—nowuse ethanol as an oxygenate in gasoline.

Reduce Growth inVehicle Travel

Improve Transit ServiceBetter bus and rail service could reducethe amount citizens need to drive. Exist-ing bus service could be improved withmore frequent service and extendedhours. In relatively low density neighbor-hoods and shopping areas, small shuttlebuses can carry passengers to major buslines that are beyond walking distance.Smaller cities and towns that do not havetransit should establish bus service.Carpools and vanpools can help serveareas not accessible to transit.

Rail transit options need to be ex-panded. In the Baltimore area, a compre-hensive light-rail network could carrycommuters and visitors from residentialareas around the city to major destina-tions. Building the Purple Line wouldlink Bethesda, Silver Spring, College Parkand New Carrollton by rail, reducing theneed to drive.

Reduce CommutingEmployers can help organize and pro-mote ride-sharing programs by pairingdrivers with similar commutes, offeringpreferred parking to carpools, and pro-viding a ride home if an employee has amid-day emergency or needs to stay atwork late.

Employers can also encourage andprovide the infrastructure fortelecommuting. Assistance installing tele-communications equipment in a homecombined with allowing staff to workfrom home for part of the week can raisean employee’s overall productivity andreduce commuting at the same time.

Expand Walking and Biking OptionsMany trips can be completed on foot or

Policy Recommendations 31

bicycle instead of in a car, but the lack ofsafe routes for walking or cycling deterspeople. Sidewalks with pedestrian ameni-ties such as benches and trees, and shopsoriented toward customers on foot ratherthan in cars can encourage more peopleto walk. Changes to road design can slowtraffic, making it easier and safer forpedestrians and cyclists to cross busyintersections.

Link Insurance to Miles DrivenFor almost all drivers, insurance is a “fixedcost,” meaning that they pay the sameamount each year regardless of how muchthey drive. As a result, when drivers con-sider the cost of driving extra miles, in-surance expenses do not come into play.Offering insurance on a cents-per-milebasis can encourage car owners to driveless by making apparent the full costs ofeach mile driven.

Private insurers could offer cents-per-mile insurance that allows drivers to

purchase insurance by the mile. Driverswould have a direct financial incentive todrive less. Such insurance also can pro-vide a benefit to senior citizens and oth-ers who drive less than average.

Promote Smart GrowthCompact development can reduce howmuch people need to drive. Many exist-ing developments in Maryland are spreadout, placing jobs and shops out of easywalking distance of homes. New hous-ing and shopping projects could be con-structed to encourage trips on foot or bikeor by transit, allowing residents the op-tion of not driving. For example, transit-oriented development concentrateshomes and shops near transit hubs to fa-cilitate the use of transit.

There are many good policies to pro-mote smart growth, and many good rea-sons to support them. Global warmingconcerns should be central among thosereasons.


P rojections of future global warmingpollution from automobiles dependa great deal on the assumptions

used. This section details the assumptionswe made about future trends and explainsthe methodology we used to estimate theimpact of various programs.

Baseline Light-Duty Vehicle CarbonDioxide EmissionsCarbon dioxide emissions from light-duty vehicles (cars and light trucks) inMaryland in 1990 and 2000-2004 werebased on state-specific motor gasolineusage data from U.S. Department of En-ergy, Energy Information Administration(EIA), State Energy Data.91 Fuel con-sumption data for the transportation sec-tor in BTU was converted to carbondioxide emissions based on conversionfactors from EIA, Annual Energy Outlook2003, Appendix H and EIA, Emissions ofGreenhouse Gases in the United States 2001,Appendix B. The proportion of transpor-tation-sector gasoline emissions attribut-able to light-duty vehicles was estimatedby dividing energy use by light-duty

vehicles by total transportation-sectormotor gasoline use as reported in EIA,Annual Energy Outlook 2006.

Vehicle-Miles TraveledHistoric vehicle-miles traveled data forMaryland were obtained from the Mary-land State Highway Administration,Travel-Millions of Annual Vehicle Miles,downloaded from www.sha.state.md.us/s h a s e r v i c e s / t r a f f i c r e p o r t s /vehicle_miles_of_travel.pdf, 30 August2006. Projected VMT was calculated onthe assumption that 1995-2005 growthrates will continue in the future.

VMT Percentages by Vehicle TypeTo estimate the percentage of vehicle-miles traveled accounted for by cars andlight-duty trucks, we relied on twosources of data: actual VMT splits by ve-hicle type for 2000 through 2002 fromthe Federal Highway Administration,Highway Statistics series of reports andprojections of future VMT splits outputfrom the EPA’s MOBILE6 mobile sourceemission estimating model.

Assumptions and Methodology

Assumptions and Methodology 33

To calculate Maryland-specific data onVMT splits, we obtained annual regis-tration data from Highway Statistics,Tables MV-1 and MV-9 for 1996 through2003, and from Table MV-201 for 1990through 1995. Because data from 1995and earlier do not include separate fig-ures for light-duty trucks, we estimatedlight-duty trucks as a percentage of allregistered trucks using the 1996 ratio re-ported in MV-9. We then multiplied thenumber of registered vehicles by the av-erage miles driven per vehicle type, as re-ported in FHWA Table VM-1. From this,we obtained a VMT split between carsand light-duty trucks.

EPA’s projections of the VMT splitamong cars and light-duty trucks assignsignificantly more VMT to light-dutytrucks than has been the case over the pastseveral years, according to FHWA data.Recent rises in fuel prices have promptedmore consumers to purchase cars insteadof trucks than has been the case for sev-eral years, but it is too early to predicthow long or significant this trend mightbe. Thus, for this analysis, we incorpo-rate EPA’s long-term projection that lighttrucks will represent an increasing por-tion of light-duty vehicle sales.

In order to estimate a trend that re-flects both the more car-heavy currentmakeup of VMT and the long-term trendtoward increasing travel in light trucks,we created two curves, one extrapolatingthe continued linear decline in the carportion of light-duty VMT based ontrends in FHWA data from 1990 to 2004and another using the EPA MOBILE6estimates. We then assumed that the splitin VMT would trend toward the EPAestimate over time, so that by 2020, carsare responsible for approximately 50 per-cent of light-duty VMT. (See Figure 10.)

VMT in the light-truck category werefurther disaggregated into VMT by“light” light trucks (in the CaliforniaLDT1 category) and heavier light trucks(California LDT2s), per EPA, Fleet Char-acterization Data for MOBILE6: Develop-ment and Use of Age Distributions, AverageAnnual Mileage Accumulation Rates, andProjected Vehicle Counts for Use in MO-BILE6, September 2001.

VMT Percentages by Vehicle AgeVehicle-miles traveled by age of vehiclewere determined based on VMT accu-mulation data presented in EPA, Fleet

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Figure 10. Percentage of Light-Duty Vehicle-Miles Traveled in Cars

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2020


Characterization Data for MOBILE6: De-velopment and Use of Age Distributions,Average Annual Mileage AccumulationRates, and Projected Vehicle Counts for Usein MOBILE6, September 2001.

Vehicle Carbon Dioxide EmissionsPer-mile carbon dioxide emissions fromvehicles were based on assumed levels ofcarbon dioxide emissions per gallon ofgasoline (or equivalent amount of otherfuel), coupled with assumptions as tomiles-per-gallon fuel efficiency.

For conventional vehicles, a gallon ofgasoline was assumed to produce 8,869grams (19.6 pounds) of carbon dioxide.This figure is based on carbon coefficientsand heat content data from EIA, Emis-sions of Greenhouse Gases in the UnitedStates 2001, Appendix B. Fuel economyestimates were based on EPA laboratoryfuel economy values from EPA, Light-Duty Automotive Technology and FuelEconomy Trends: 1975 Through 2004, April2004, multiplied by a degradation factorobtained from EIA, Assumptions to theAEO 2006. (The degradation factor rep-resents the degree to which real-worldfuel economy falls below that reported asa result of EPA testing.)

For hybrid-electric vehicles used tocomply with AT-PZEV requirements,fuel economy was estimated to exceedthat of conventional vehicles by 30 per-cent, per National Research Council,National Academy of Engineering, TheHydrogen Economy: Opportunities, Costs,Barriers and R&D Needs, the NationalAcademies Press, 2004. This same docu-ment provided the assumption that hy-drogen fuel-cell vehicles would achieve58 percent greater fuel economy thanconventional vehicles. This figure wasthen input into the Argonne NationalLaboratory’s Greenhouse Gases Regu-lated Emissions and Energy Use in Trans-portation (GREET) model version 1.5a

to produce an estimated grams CO2/gasoline gallon equivalent for fuel-cellvehicles of 3,816 grams, which was thenused to estimate emissions from hydro-gen fuel-cell vehicles manufactured tocomply with the LEV II program. (Fuel-cycle emissions from hydrogen fuel-cellvehicles were used in lieu of direct tailpipeemissions since fuel-cell vehicles emit nopollution from the tailpipe and it was as-sumed that the hydrogen fuel—and itsassociated emissions—would be createdwithin Maryland. Estimated emissions fromelectricity used to generate hydrogen wre not adjusted for Maryland’s powermix.)

For the global warming emission stan-dards, we assumed percentage reductionsin per-mile vehicle emissions as describedin California Environmental ProtectionAgency, Air Resources Board, Staff Re-port: Initial Statement of Reasons for Pro-posed Rulemaking, Public Hearing toConsider Adoption of Regulations to ControlGreenhouse Gas Emissions from Motor Ve-hicles, 6 August 2004.

Emissions from vehicles complyingwith the standards were estimated bymultiplying the percentage reduction inemissions attributed to the standards foreach model year by the 2004 emissionslevel for that class of vehicles. For all yearsuntil 2016, vehicle sold by intermediateand small vehicle manufacturers were as-sumed not to comply with the standards(due to an exemption in the Californialaw) and were assigned emissions at thesame rate as calculated for the referencecase scenario. Intermediate and smallmanufacturers were assumed to sell 12.7percent of cars and 6 percent of lighttrucks, based on national estimates fromWard’s Communications, 2003 Ward’sAutomotive Yearbook, 233. In 2016 andsubsequent years, small and intermedi-ate manufacturers were assumed toachieve carbon dioxide emission reduc-tions of 25 percent for cars and 18 per-

Executive Summary 35

cent for light trucks per a complianceoption for those manufacturers describedin Title 13 CCR 1961.1(C).

Advanced Technology ProgramImplementationIn calculating emission reductions result-ing from LEV II’s advanced technologyprogram, we assumed implementation ofthe program beginning in model year2011 with the same requirements as theCalifornia program. Vehicles meeting theAT-PZEV standards were assumed to be“Type D” Hybrids (similar to the ToyotaPrius), while vehicles meeting pure ZEVstandards were assumed to be hydrogenfuel-cell vehicles whose fuel was producedfrom natural gas.

Percentages of vehicles meetingPZEV, AT-PZEV and pure ZEV criteriawere estimated in the following manner:

• Light-duty vehicle sales in Marylandfor each category (cars and lighttrucks) were estimated based on year2004 new vehicle registration figuresfrom Alliance of Automobile Manu-facturers, Light Truck Country,downloaded from autoalliance.org/download/lighttruck.pdf, 27 October2005, with the light truck categorydivided into heavy and light light-duty trucks using EPA fleet composi-tion estimates as described above.These figures were then multipliedby the percentage of sales subject tothe advanced technology programfor each year.

• This number was multiplied by 0.9to account for the six-year time lag incalculating the sales base subject tothe advanced technology program.(For example, a manufacturer’srequirements in the 2009 through2011 model years are based onpercentages of sales during modelyears 2003 through 2005.)

• Where necessary, these values weremultiplied by the percentage ofvehicles supplied by major manufac-turers versus all manufacturers ascalculated from Ward’s Communica-tions, 2003 Ward’s Automotive Year-book, 233. (Non-major manufacturersmay comply with the entire advancedtechnology program requirement bysupplying PZEVs.)

• This value was then multiplied by thepercentage sales requirement toarrive at the number of advancedtechnology program credits thatwould need to be accumulated ineach model year.

• The credit requirement was dividedby the number of credits received byeach vehicle supplied as described inCalifornia Environmental ProtectionAgency, Air Resources Board, FinalRegulation Order: The 2003 Amend-ments to the California Zero EmissionVehicle Regulation, 9 January 2004.

• The resulting number of vehicles wasthen divided by total light-dutyvehicle sales to arrive at the percent-age of sales required of each vehicletype.

• No pure ZEVs were assumed to berequired for sale in Maryland untilthe 2012 model year. For the 2012through 2017 model years, in whichthe pure ZEV requirement is basedon a specific number of Californiasales, we divided the annual pureZEV requirement in the Californiaregulations by the number of newvehicles registered in California in2001 per Ward’s Communications,2002 Ward’s Automotive Yearbook, 272.We assumed that the same percent-age would apply to vehicle sales inMaryland.

It was assumed that manufacturers


would comply with ZEV and AT-PZEVrequirements through the sale of fuel-celland hybrid passenger cars. While heavierlight trucks are also covered by the ad-vanced technology program, manufactur-ers have the flexibility to use creditsaccumulated from the sale of cars toachieve the light-truck requirement. Per-centages of various vehicle types assumedto be required under the advanced tech-nology program are depicted in Figure8, page 24 (assuming a roughly 60/40 per-centage split between light-truck salesand car sales throughout the entire period).

Fleet Emissions ProjectionsBased on the above data, two scenarioswere created: a “Base Case” scenariobased on projected trends in vehicle fueleconomy, VMT and vehicle mix and a“Global Warming Pollution Standards”scenario based on the percentage emis-sion reductions proposed by the CARBstaff in August 2004. Each scenario be-gan with data from 2004 and continuedthrough 2020.

Projected emissions were based on theyear-to-year increase (or decrease) inemissions derived from the estimationtechniques described above. These year-to-year changes were then applied to the2004 baseline emission level to createprojections through 2020.

Other AssumptionsIn addition to the above, we made thefollowing assumptions:

• Rebound effects – Research hasshown that improved vehicle fuelefficiency often results in an increase

in vehicle-miles traveled. By reduc-ing the marginal cost of driving,efforts to improve efficiency providean economic incentive for additionalvehicle travel. Studies have foundthat this “rebound effect” mayreduce the carbon dioxide emissionsavings of fuel economy-improvingpolicies by as much as 20 to 30percent.92 To account for this effect,carbon dioxide reductions in each ofthe scenarios were discounted by 5percent. This estimate is moderate:in its own analysis using California-specific income and transportationdata, CARB estimated a reboundeffect ranging from 7 percent to lessthan 1 percent.93

• Mix shifting – We assumed thatneither of the policies under studywould result in changes in the classof vehicles purchased by Marylandresidents, or the relative amount thatthey are driven (rebound effectexcluded). In addition, we assumedthat the vehicle age distributionsassumed by EPA remain constantunder each of the policies. In otherwords, we assumed that any increasein vehicle prices brought about bythe global warming emission stan-dards would not dissuade consumersfrom purchasing new vehicles orencourage them to purchase lighttrucks when they would otherwisepurchase cars (or vice versa). Mixshifting impacts such as these arequite complex and modeling themwas beyond the scope of this report,but they do have the potential tomake a significant impact on futurecarbon dioxide emissions.

Notes 37

Notes

1 Meszler Engineering Services, GHG EmissionStandards for Vehicles: An Overview of California’sPavley Requirements, presentation to RhodeIsland GHG Process Stakeholders, 28 April2005.2 Malte Meinshausen, “What Does a 2˚C TargetMean for Greenhouse Gas Concentrations? ABrief Analysis Based on Multi-Gas EmissionPathways and Several Climate SensitivityUncertainty Estimates,” in Hans JoachimSchnellnhuber, ed., Avoiding Dangerous ClimateChange, Cambridge University Press, 2006.Meinshausen estimated that carbon dioxidestabilization at 450 ppm would result in a meanprobability of 54 percent that global averagetemperatures would increase by more than 2˚Cversus pre-industrial levels. By contrast,stabilizing carbon dioxide concentrations at 400ppm would reduce the mean probability ofexceeding a 2˚C increase to 28 percent.3 Ibid.4 Intergovernmental Panel on Climate Change,IPCC Third Assessment Report – Climate Change2001: Summary for Policy Makers, The ScientificBasis, 2001.5 Ibid. Temperatures in the past 150 years havebeen measured; earlier temperatures are derivedfrom proxy measures such as tree rings, corals,and ice cores.6 J. Hansen, et al., NASA Goddard Institute forSpace Studies, GISS Surface Temperature Analysis:Global Temperature Trends: 2005 Summation,

downloaded from data.giss.nasa.gov/gistemp/2005/, 23 May 2006.7 “first half of 2006 … hottest” from DeborahZabrenko, “2006 Sets Heat Record for U.S.,”Reuters, 20 July 2006; “2005 … hottest year”from J. Hansen, et al., NASA Goddard Institutefor Space Studies, GISS Surface TemperatureAnalysis: Global Temperature Trends: 2005Summation, downloaded from data.giss.nasa.gov/gistemp/2005/, 23 May 2006.8 Union of Concerned Scientists, GlobalWarming 101: 2005 Vies for Hottest Year onRecord, downloaded from www.ucsusa.org/global_warming/science/recordtemp2005.html,23 May 2006.9 U.S. Environmental Protection Agency, Officeof Policy, Planning and Evaluation, ClimateChange and Maryland, September 1998.10 Maryland State Climatologist Office,Maryland Temperature and Precipitation Trends,downloaded from www.atmos.umd.edu/~climate/, 28 August 2006.11 See note 9.12 See note 4.13 J.T. Overpeck, et al., “Arctic System onTrajectory to New, Seasonally Ice-Free State,”Eos, 86(34):309-316, August 2005.14 See note 4.15 Ibid.16 U.S. Environmental Protection Agency,Global Warming – Impacts: Chesapeake Bay,


downloaded from yosemite.epa.gov/oar%5Cglobalwarming.nsf/content/ImpactsCoastalZonesChesapeakeBay.html, 23May 2006.17 National Oceanic and Atmospheric Adminis-tration, Subsidence and Sea Level Rise in Louisiana:A Study in Disappearing Land, 21 July 2003.18 See note 9.19 Tom Pelton, “New Maps Highlight Vanish-ing E. Shore,” Baltimore Sun, 30 July 2004. Thestate is sinking because glaciers compress theland beneath them and create a bulge insurrounding areas, such as Maryland. With theglaciers now gone, the bulge beneath Marylandis subsiding.20 Net effect: U.S. Environmental ProtectionAgency, National Park Service, and U.S. Fishand Wildlife Service, Climate Change, Wildlife,and Wildlands: Chesapeake Bay and AssateagueIsland, downloaded from yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BPPVT/$File/CS_Ches.pdf, 19 October2005; 3,100 miles: See note 9; 260 acres: Seenote 19.21 U.S. Environmental Protection Agency,National Park Service, and U.S. Fish andWildlife Service, Climate Change, Wildlife, andWildlands: Chesapeake Bay and Assateague Island,downloaded from yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BPPVT/$File/CS_Ches.pdf, 19 October2005.22 Ibid.23 See note 4.24 Kerry Emanuel, “Increasing Destructivenessof Tropical Cyclones Over the Last 30 Years,”Nature, 436:686-688, 4 August 2005.25 P.J. Webster, et al., “Changes in TropicalCyclone Number, Duration, and Intensity in aWarming Environment,” Science,309(5742):1844-1846, 16 September 2005.26 National Oceanic and Atmospheric Adminis-tration, Noteworthy Records of the 2005 AtlanticHurricane Season, originally published 29November 2005, updated 13 April 2006.27 University of Maryland Center for Environ-mental Science, Integration ApplicationNetwork, Hurricane Isabel and Sea Level Rise,downloaded from ian.umces.edu/pdfs/iannewsletter6.pdf, 7 September 2006.28 Michael Kearney and J. Court Stevenson,University of Maryland, Dissecting and Classifyingthe Impacts of Historic Hurricanes on Estuarine

Systems (presentation), available atwww.climate.org/topics/weather/hurricane-isabel.shtml, 7 September 2006.29 See note 3.30 Rachel Warren, “Impacts of Global ClimateChange at Different Annual Mean GlobalTemperature Increases,” in Hans JoachimSchnellnhuber, ed., Avoiding Dangerous ClimateChange, Cambridge University Press, 2006.31 James Hansen, “A Slippery Slope: HowMuch Global Warming Constitutes ‘DangerousAnthropogenic Interference?’” Climatic Change,68:269-279, 2005.32 See note 3 and note 30.33 Ibid.34 National Research Council, Abrupt ClimateChange: Inevitable Surprises, National AcademiesPress, Washington, D.C., 2002.35 Corresponds to scenario A1F1 in Intergov-ernmental Panel on Climate Change, IPCCThird Assessment Report – Climate Change 2001:Synthesis Report, 2001.36 See note 9.37 Ibid.38 James Titus and Charlie Richman, “Maps ofLands Vulnerable to Sea Level Rise: ModeledElevations Along the U.S. Atlantic and GulfCoasts,” Climate Research, 2001.39 Ibid.40 James Titus, “Rising Seas, Coastal Erosion,and the Takings Clause: How to Save Wetlandsand Beaches Without Hurting PropertyOwners,” Maryland Law Review, Volume 57,1998.41 See note 38.42 Chesapeake Bay Program, Dissolved OxygenForecast, downloaded fromwww.chesapeakebay.net/newsdo100305.htm, 19October 2005.43 See note 21.44 Virginia Institute of Marine Sciences, 2006Field Observations and a First Look at the Photogra-phy, Summer 2006, available at www.vims.edu/bio/sav/2006obs.html.45 American Bird Conservancy and NationalWildlife Federation, Global Warming andSongbirds: Maryland, 2002.46 See note 21.47 Ibid.48 Maryland Department of Natural Resources,Maryland Wildlife Diversity Conservation Plan,

Notes 39

downloaded from www.dnr.state.md.us/wildlife/WCDP_Introduction_20050926.pdf, 19October 2005.49 See note 9.50 Ibid.51 Ibid.52 Ibid.53 World Meteorological Organization, FirstWMO Greenhouse Gas Bulletin: Greenhouse GasConcentrations Reach New Highs in 2004 (pressrelease), 14 March 2006.54 See note 4.55 C.D. Keeling and T.P. Whorf, CarbonDioxide Information Analysis Center, OakRidge National Laboratory, “Atmospheric CO2Records from Sites in the SIO Air SamplingNetwork,” in Trends: A Compendium of Data onGlobal Change, 2005.56 Energy Information Administration,Emissions of Greenhouse Gases in the United States2004, December 2005.57 Data on emissions within transportationsector was calculated as fuel use multiplied bythe carbon co-efficient of each fuel. Fuel usedata: Energy Information Administration, StateEnergy Consumption, Price and ExpenditureEstimates, Table 11: Transportation Sector EnergyConsumption Estimates, 1960-2002, Maryland, 30June 2006. Carbon co-efficients: EnergyInformation Administration, Documentation forEmissions of Greenhouse Gases in the United States2003, May 2005.58 See note 56.59 California Environmental Protection Agency,Air Resources Board, Draft Staff ProposalRegarding the Maximum Feasible and Cost-EffectiveReduction of Greenhouse Gas Emissions from MotorVehicles, 14 June 2004, 8.60 U.S. Environmental Protection Agency,Inventory of U.S. Greenhouse Gas Emissions andSinks, 1990-2002, 15 April 2004.61 James Hansen and Larissa Nazarenko, “SootClimate Forcing Via Snow and Ice Albedos,”Proceedings of the National Academy of Sciences,101(2), 2004.62 U.S. Department of Energy, Energy Effi-ciency and Renewable Energy, MarylandEstablishes Appliance Efficiency Standards, 1 March2004.63 Code of Maryland, Public Utility Companies,§7-701 et seq. (2005).64 Maryland State Highway Administration,

Annual Vehicle Miles of Travel, downloaded fromwww.sha.state.md.us/SHAServices/trafficReports/Vehicle_Miles_of_Travel.pdf, 28August 2006.65 Ibid.66 Stacy C. Davis, Susan W. Deigel, Center forTransportation Analysis, Oak Ridge NationalLaboratory, Transportation Energy Data Book:Edition 22, September 2002, Chapter 7. Thefederal government has approved an slightincrease in light truck CAFE standards to takeeffect for the 2005 model year.67 The federal law that established CAFEstandards also established the means for testingof vehicles to determine compliance with thestandards. It has long been recognized that thesetesting methods overstate the “real world” fueleconomy of vehicles. EPA has begun to includeadjusted figures in its reporting of fuel economytrends and, in its 2004 report, included anestimate of real-world vehicle mileage based onincreases in the percentage of urban driving. Inthis report, all discussions of vehicle fueleconomy will refer to “real world” efficiencylevels rather than “EPA rated” levels.68 U.S. Environmental Protection Agency,Light-Duty Automotive Technology and FuelEconomy Trends: 1975 Through 2004, AppendixC, April 2004.69 Ibid.70 Real world fuel economy: See note 68. CAFEstandards: U.S. Department of Transportation,Summary of Fuel Economy Performance, March2003.71 See note 68.72 Ibid.73 U.S. Environmental Protection Agency, FleetCharacterization Data for MOBILE6: Developmentand Use of Age Distributions, Average AnnualMileage Accumulation Rates, and Projected VehicleCounts for Use in MOBILE6, September 2001;MOBILE6 run conducted by MASSPIRGEducation Fund based on national defaults,January 2003.74 Conference of New England Governors andEastern Canadian Premiers, Climate ChangeAction Plan 2001, August 2001.75 See “Assumptions and Methodology” formethod of calculation.76 State of California, Air Resources Board,ZEV Technology Review, 1 June 2006.77 2004 sales: Toyota, Toyota Reaches Two Millionin Sales For The First Time in 47-Year History


(press release), 4 January 2005; Honda, AmericanHonda Sets New All-Time Sales Record (pressrelease), 4 January 2005; and Steve Geimann,Bloomberg, “Ford Expands Lineup of Gas-Electric Hybrid Vehicles (Update 3),” 9 January2005. 2005 sales: J.D. Power and Associates,Sales of Hybrid-Electric Vehicles Expected to Grow268 Percent by 2012 (press release), 4 January 2006.78 California Environmental Protection Agency,Air Resources Board, Clean Vehicle Search resultsfor hybrid-electric vehicles, downloaded fromwww.arb.ca.gov/msprog/ccvl/ccvl20042006index.htm, 30 August 2006.79 California Environmental Protection Agency,Air Resources Board, Future Clean Cars,downloaded from www.driveclean.ca.gov/en/gv/vsearch/upcoming.asp, 30 August 2006.80 Based on estimated fuel-efficiency improve-ment factor of 1.45 from hybrid-electric vehiclesversus conventional vehicles in NationalResearch Council, National Academy ofEngineering, The Hydrogen Economy: Opportuni-ties, Costs, Barriers and R&D Needs, The NationalAcademies Press, 2004.81 The reasons behind the lack of marketsuccess of the EV-Plus, EV1 and similar electricvehicles are complex, and may have much to dowith automakers’ failure to properly markettheir vehicles to the public.82 California Assembly Bill 1493, adopted 29July 2002.83 California Environmental Protection Agency,Air Resources Board, Staff Report: InitialStatement of Reasons for Proposed Rulemaking,Public Hearing to Consider Adoption of Regulationsto Control Greenhouse Gas Emissions from MotorVehicles, 6 August 2004.84 California Environmental Protection Agency,Air Resources Board, Draft Staff ProposalRegarding the Maximum Feasible and Cost-EffectiveReduction of Greenhouse Gas Emissions from MotorVehicles, 14 June 2004.85 California Environmental Protection Agency,Air Resources Board, Addendum Presenting andDescribing Revisions to: Initial Statement of Reasonsfor Proposed Rulemaking, Public Hearing toConsider Adoption of Regulations to Control

Greenhouse Gas Emissions from Motor Vehicles, 10September 2004.86 See note 1.87 See note 83 and note 85.88 See note 1.89 Short Term Actions for Implementation to ReduceGreenhouse Gas Emissions in Connecticut—InitialProgress, Governor’s Steering Committee onClimate Change, 15 November 2004.90 U.S. Department of Agriculture, AgriculturalResource Service, “Book: Cropland Helps EaseCO2 and Control Greenhouse Effect,” News andEvents, 29 September 1998.91 U.S. Department of Energy, Energy Infor-mation Administration (EIA), State EnergyConsumption, Price and Expenditures Estimates,Consumption, 1960-2002, 30 June 2006; and U.S.Department of Energy, Energy InformationAdministration (EIA), State Energy Consumption,Price and Expenditures Estimates, Updates forRecent Years, 9 August 2006.92 Paul Schimek, “Gasoline and Travel DemandModels Using Time Series and Cross-SectionData from the United States,” TransportationResearch Record, No. 1558 (1996), 83; U.S.General Accounting Office, Energy Policy Act of1992: Limited Progress in Acquiring AlternativeFuel Vehicles and Reaching Fuel Goals, February2000.93 See note 83. Earlier analysis by CARBsuggested that even deeper cuts in vehicleemissions could be made more quickly. CARB’sinitial draft proposal for implementation of thestandards called for cost-effective emissionreductions of 22 percent from cars and 24percent from light trucks in the near term. Overthe medium term (2012 to 2014), cost-effectivereductions of 32 percent for cars and 30 percentfor light-trucks were deemed feasible. Inaddition, the standards were assumed to bephased in much more quickly than underCARB’s most recent proposal. See CaliforniaEnvironmental Protection Agency, Air Re-sources Board, Draft Staff Proposal Regarding theMaximum Feasible and Cost-Effective Reduction ofGreenhouse Gas Emissions from Motor Vehicles, 14June 2004.

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