Climate Change: Current Issues and Policy Tools

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Climate Change: Current Issues and

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March 6, 2009

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RL34513

CRS Report for Congress

Prepared for Members and Committees of Congress

Climate Change: Current Issues and Policy Tools

Summary

On June 2, 2008, the Senate agreed to consider a bill (S. 3036) to control greenhouse gas

emissions in the United States. In the 111th Congress, leadership in both chambers have

announced their intentions to pass bills in 2009 to reduce greenhouse gas emissions. These

actions are indicative of the pressures Members of Congress increasingly face on whether and

how to address human-induced climate change. Contentious debates scrutinize issues of science,

economics, values, geopolitics and a host of other concerns. Deliberations also weigh the

appropriateness of alternative policy tools and program designs. The economic stakes are

potentially large—with both the costs of controls and the “costs of inaction” ranging, by some

estimates, into trillions of dollars over several decades.

A major international assessment released in 2007 concluded that the Earth’s climate had warmed

unequivocally over the past century, and that elevated levels of so-called “greenhouse gases”

(GHGs) were likely responsible for a major portion of the observed warming. Elevated

concentrations of GHGs in the atmosphere are due mostly to human activities, especially

emissions from use of fossil fuels, clearing of land, and some industrial processes. Continued

population and economic growth, with dependence on fossil fuels and needs for expanding

agricultural lands, are expected to drive GHG emissions and induced climate change over the 21st

Century to levels never experienced by human civilizations. While benefits may accrue to some

people who may experience a limited amount of climate change, the aggregate effects are

expected to become increasingly adverse, with people living in dry regions or along low-lying

coasts, and people with low incomes, expected to be especially vulnerable. Adaptations can

moderate the impacts and expand opportunities, but at a cost. Besides the overall costs of climate

change, key concerns include the distributional effects within and across generations, how to

value ecological impacts, and the potential for abrupt and irreversible changes. While important

uncertainties remain concerning future climate change and its impacts, many experts are

convinced that the evidence calls for U.S. action to abate GHG emissions. Others argue that

mandatory controls would be premature, unnecessary or too costly.

For decision-makers considering actions to address climate change, an assortment of policy

instruments is available; studies suggest that a combination could be most effective in achieving

various climate policy objectives. Current policy attention has focused on “cap and trade”

strategies to reduce GHG emissions, with additional policy tools aimed at promoting the

technology development considered necessary to slow climate change significantly. In parallel,

growing attention is being given to supporting adaptations to expected future changes, as well as

to strategies to gain effective international engagement in reducing GHGs. One significant

obstacle to consensus is concern about the potential costs of abating GHG emissions, since deep

reductions would require extraordinary changes in energy use and technologies. Studies suggest

that efficiently designed programs could moderate the costs of reducing GHG emissions;

technically and politically, though, an “efficiently designed” program may not be realistic. Policy

options can ease the adjustments required and modify the distribution of costs—or potential

wealth embodied in distribution of emission allowances—across specific sectors or populations.

A core challenge of policy design, then, is balancing the climate effectiveness of a policy, the

economic costs, and its distributional effects.

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Climate Change: Current Issues and Policy Tools

Contents

Introduction ................................................................................................................................1

Part One: Current Climate Change Issues ....................................................................................2

Climate Change Science........................................................................................................2

Observed Changes in Global Climate ..............................................................................2

Causes of Observed Climate Change...............................................................................2

Sources of GHG Emissions, and Removals from the Atmosphere..........................................3

Projections of Greenhouse Gas-Induced Climate Change.......................................................5

Potential Impacts of Projected Climate Change .....................................................................6

Proposed Greenhouse Gas Concentration Targets ..................................................................7

Program Design and the Costs of GHG Mitigation ................................................................8

Distributional Impacts of Programs .................................................................................9

Climate Change and Other Policy Issues: Commonality or Conflict? ...............................9

U.S. Costs of GHG Mitigation ...................................................................................... 10

Global Costs of GHG Mitigation................................................................................... 11

Benefits of Mitigating Climate Change................................................................................ 11

Inadequate Data, Tools, and Understanding of Impacts .................................................. 11

Global Costs of Climate Change ................................................................................... 12

Potential Costs of Climate Change to the U.S. Economy ............................................... 13

“Co-Benefits” and Trade-offs of GHG Mitigation.......................................................... 14

Importance of the Distribution of Losses (or Gains)............................................................. 15

Part Two: The International and Domestic Policy Fields ............................................................ 15

Status of International Cooperation on Climate Change ....................................................... 15

The United Nations Framework Convention on Climate Change ................................... 15

The Kyoto Protocol....................................................................................................... 16

The United States Rejected the Kyoto Protocol.............................................................. 16

“Common but Differentiated Responsibilities” .............................................................. 16

The Bali Action Plan ..................................................................................................... 16

Current Domestic Policy on Climate Change....................................................................... 17

Goal.............................................................................................................................. 17

Federal Policies............................................................................................................. 17

Funding ........................................................................................................................ 18

Legislative Actions........................................................................................................ 18

Regional, State, and Local GHG Policies....................................................................... 18

Climate Change Litigation ............................................................................................ 19

Part Three: The Policy Tool Box ............................................................................................... 19

Regulatory and Market Tools to Reduce Greenhouse Gases................................................. 20

Source-by-Source Regulations ...................................................................................... 20

Market Mechanisms ...................................................................................................... 20

Design Choices in Cap-and-Trade Programs.................................................................. 21

Distributing the Revenues from Taxes or Sales .............................................................. 23

Market Facilitation Tools .................................................................................................... 23

Tools to Stimulate Technological Change ............................................................................ 24

Unintended Consequences for Technology Incentives.................................................... 25

Options to Ease the Economic Transition ............................................................................ 25

International Policy Tools.................................................................................................... 26

Tools to Stimulate Adaptation to Climate Change................................................................ 27

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Choices Ahead for Policy Makers.............................................................................................. 27

Further Information................................................................................................................... 28

Figures

Figure 1. Estimated Sectoral and Greenhouse Gas Shares of Global Emissions in 2005 ...............4

Figure 2. Estimated Top 20 Emitters of Greenhouse Gases in 2005..............................................5

Contacts

Author Contact Information ...................................................................................................... 28

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Introduction

The Earth’s surface has warmed by 1.1o to 1.5o Fahrenheit since the Industrial Revolution and

precipitation has increased over the past century, although some regions have become wetter

while some have become drier. Increases in ocean temperatures, altered wind patterns, extreme

weather events, melting glaciers and sea ice, and timing of seasons have also been observed. The

Intergovernmental Panel on Climate Change (IPCC) in 2007 declared that “[w]arming of the

climate system is unequivocal....” and that most of the observed change since the 1970s is likely

due to greenhouse gases emitted as a result of human activities. 1 Experts project that if

greenhouse gas (GHG) emissions are not abated well below current levels, the Earth’s climate

will warm further—to levels never experienced by human civilizations. If, and as, the climate

moves further from its present state, it will reconfigure the patterns to which current human and

ecological systems are adapted, and the risk of abrupt changes will increase.

Understanding of the magnitude, causes, and implications of climate change continues to grow.

But alongside efforts to further that understanding, a sense of urgency is spurring many

international, national, regional, and local policymakers, industry leaders, non-governmental

organizations (NGOs), and citizens to mobilize toward more concrete actions. Concern about

poorly understood but potentially catastrophic impacts of human-induced climate change drives

the impetus to identify, evaluate, and initiate concrete policy actions to address human

activities—such as the emissions of GHGs, land use changes, and forestry practices—believed to

contribute to climate change. In parallel, growing attention is being given to characterizing and

supporting adaptations to changes already observed or expected future changes.

Domestic actions to address climate change are moving independently across many fronts. In the

110th Congress, numerous bills have been proposed to address climate change research and

policy; one bill (S. 2191) that would cap and reduce greenhouse gas emissions was reported by

the Senate Committee on Environment and Public Works and the Senate agreed on June 2, 2008

to consider the bill (now S. 3036). The Supreme Court in 2007 ruled that the Administration must

consider regulating greenhouse gases from motor vehicles as air pollutants, and President George

W. Bush in 2008 proposed a qualified national goal for U.S. greenhouse gas emissions to peak by

2025 and then decline. States and localities have moved forward with their own plans and

regulations in lieu of a strong national framework. Primary concerns are the costs, which could

reach trillions of dollars over coming decades, depending on policy choices; the distribution of

those costs; and the effectiveness of policies, with the knowledge that U.S. greenhouse gas

reductions would achieve success only if sufficient international cooperation can be achieved as

well.

Debate internationally has revived over how nations may commit to mitigation, adaptation, and

technology actions beyond 2012, the end of the current commitment period of the Kyoto Protocol

to the United Nations Framework Convention on Climate Change. Negotiations are aiming to

produce a post-2012 decision by the end of 2009. U.S. domestic policy development could

influence and support international cooperation or introduce impediments, depending on how the

interplay is managed. The stakes are potentially high: the effectiveness of mitigating humaninduced climate change depends on action by all major emitters, while the costs of delay, deferral

1

Intergovernmental Panel on Climate Change Working Group I. Climate Change 2007: The Physical Basis.

Cambridge, UK: Cambridge University Press, 2007 (p. 1).

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or ineffectiveness have been projected by some analysts to reach many trillions of dollars over

coming decades.

This report does not discuss or analyze current legislative proposals. Rather, it introduces the

reader to fundamentals of the climate change issue. Part One summarizes current understandings

and controversies concerning the science, economics, international cooperation, and other aspects

of the climate change policy problem. Part Two is a brief update on the status of domestic and

international policies. Part Three outlines the policy toolbox seen as being available to

policymakers to address the challenge as they define the emerging legislative agenda.

Part One: Current Climate Change Issues

Climate Change Science2

Observed Changes in Global Climate

The Earth’s surface has warmed by 1.1o to 1.5o Fahrenheit since the Industrial Revolution

(measured since 1880), with most warming occurring since the 1970s. Precipitation has increased

over the past century, although some regions have become wetter while some have become drier.

These results are consistent with scientists’ understanding of how heightened greenhouse gas

concentrations affect climate regionally. Increases in ocean temperatures, altered wind patterns,

extreme weather events, melting glaciers and sea ice, and timing of seasons have also been

observed. The Intergovernmental Panel on Climate Change (IPCC) in 2007 declared that

“[w]arming of the climate system is unequivocal.... Observational evidence from all continents

and most oceans shows that many natural systems are being affected by regional climate

changes.”3

Causes of Observed Climate Change

Although there is significant natural variability in the Earth’s climate, scientists recognized more

than a century ago that pollution from human activities could theoretically warm the Earth.

GHGs in the Earth’s atmosphere allow the Sun’s short wave-length radiation to pass through to

the Earth’s surface. Once the radiation is absorbed by the Earth and re-emitted as longer wavelength radiation, GHGs trap the heat in the atmosphere. This is often called the “greenhouse

effect.” The natural presence of GHGs (especially water vapor and carbon dioxide) in the

atmosphere warms the Earth to habitable temperatures.

Studies show that solar variability has contributed some of the observed changes in global

temperature, especially early in the 1900s. A few studies conclude that, at most, solar variability

has contributed 10% to 40% of the observed change of the 20th century.4 Further research would

2

For further information, see CRS Report RL34266, Climate Change: Science Highlights, by (name redacted).

3

Intergovernmental Panel on Climate Change Working Group I. Climate Change 2007: The Physical Basis.

Cambridge, UK: Cambridge University Press, 2007 (p. 1).

4

A number of peer-reviewed references are available from CRS upon request.

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be required to quantify how some suggested influences, for example, galactic cosmic rays,

contribute to observed climate changes.

Most scientists conclude that a majority of the Earth’s warming since the 1970s is due to GHG

emissions from human activities, especially use of fossil fuels, clearing of land, and some

industrial processes. While scientists agree that GHGs in the atmosphere are responsible for

trapping the Sun’s radiation and raising the Earth’s temperature to current levels, some scientists

disagree that projected increases in GHG concentrations would raise temperatures significantly.

Sources of GHG Emissions, and Removals from the Atmosphere

Beyond water vapor (which is thought not to be directly influenced by humans), the bestunderstood greenhouse gases include

•

carbon dioxide (CO2);

•

methane (CH4);

•

nitrous oxide (N2O); and

•

certain fluorinated compounds, including chlorofluorocarbons (CFC),

hydrochlorofluorocarbons (HCFC), hydrofluorocarbons (HFC),

perchlorofluorocarbons (PFC), sulfur hexaflouride (SF6), and nitrous trifluoride

(NF3).5

These GHGs remain in the atmosphere for decades to thousands of years and are generally wellmixed around the globe; hence, their warming effects are largely global and persist for decades to

millenia. The long atmospheric residence also means a long lag between policies to abate GHG

emissions and their full effects on the climate system.

When emissions of the long-lived GHGs are greater than their removals by, for example,

photosynthesis, the GHGs accumulate in the atmosphere: the GHG concentrations increase. The

increases of concentrations of specific GHGs since the Industrial Revolution (measured since

about 1850) include

•

CO2 by more than 33%, from about 280 parts CO2 per million (ppm) to current

levels of over 380 ppm;

•

Methane (CH4) by about 150%, although the rate of increase has declined over

the past decades to essentially no growth (but variable year-to-year);

•

Nitrous oxide (N2O) by 16%; and

•

essentially all concentrations of CFC, HCFC, HFC, PFC, and SF6.

5

Additional pollutant emissions indirectly affect climate change, largely on the local to regional scale; they include

carbon monoxide (CO), nitrogen oxides (NOx) other than N2O, and non-methane volatile organic compounds

(NMVOC), and particulate matter or aerosols. Perhaps more important, human-induced climate change and land uses

may indirectly affect water vapor in the atmosphere, influencing both global and regional climate change, including the

distribution of precipitation, and are likely to alter the reflectivity of the Earth’s surface. Compared to other effects,

these effects are poorly understood, though they may have large impacts.

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Human-related GHG emissions are partly offset by human-related carbon removals and

sequestration in growing forests, some agricultural soils, and other reservoirs. Such “sinks” offset

about 11% of U.S. GHG emissions in 2005.

Figure 1. Estimated Sectoral and Greenhouse Gas Shares

of Global Emissions in 2005

CO2 - La nd Us e and

Other

1 1%

CH4 - Energy

5%

CO2 - Fuel

Combustion

63 %

CH4 - Agriculture

7%

CH4 - Waste

3%

N2O - Agriculture

8%

HFC, PFC+SF6

1%

All Other

2%

Source: CRS graphic with estimates from International Energy Agency, CO2 Emissions from Fuel Combustion 19712005, 2007, online database. Data extracted January 16, 2008.

For the year 2005, CO2 constituted approximately 74% of the global, human contribution to longlived GHG emissions;6 CH4 was about 16%, and N2O was about 8% (Figure 1).

Globally in 2005, the top 10 emitting countries contributed about 60% of global GHG emissions,

and the top 20 emitting countries contributed about 72% of global GHG emissions.7,8 China

probably is now the leading9 emitter of human-related GHGs, likely having recently surpassed the

6

These shares exclude emissions of CFC, HCFC and other substances that are controlled to protect the stratosphere. In

policy discussions, these emissions typically are not counted as “GHG”; also, they are generally estimated as potential

emissions when they are manufactured, not as actual emissions, so the method to count them is different from other

GHG. Reducing them would, however, help to reduce climate change.

7

See also CRS Report RL32721, Greenhouse Gas Emissions: Perspectives on the Top 20 Emitters and Developed

Versus Developing Nations, by (name redacted) and (name redacted).

8

According to agreed international guidelines, countries report emissions from international bunker fuels (for

international travel and shipping) but do not include them in country totals. Emissions from international bunker fuels

were almost 1000 metric tons of CO2e in 2005, and are almost as much as the 6th largest emitting country in the world.

9

This conclusion is based on uncertain estimates of GHG emissions internationally. While the supporting data are not

precise, experts have high confidence that if recent trends prevail, China will be the largest net source of GHG by the

end of the decade.

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United States (Figure 2). Most experts expect that Chinese and other developing countries’ GHG

emissions will continue to grow more rapidly than those of the United States and other already

industrialized countries.

Figure 2. Estimated Top 20 Emitters of Greenhouse Gases in 2005

Source: CRS graphic with emission estimates from International Energy Agency, op. cit.; data extracted May 5,

2008.

Projections of Greenhouse Gas-Induced Climate Change10

The climate-related impacts borne by human and ecological systems will depend on the

combination of natural climate variability plus human-induced climate changes.11 Scientists

project that, during the 21st Century, it is very likely that rising GHG emissions, as expected with

current trends and policies, and the resulting higher concentrations in the atmosphere, will raise

the global average temperature above natural variability by at least 1.5o Celsius (2.7o Fahrenheit)

above 1990 levels. The estimates considered most likely by many scientists are for GHG-induced

10

For further information, see CRS Report RL34266, Climate Change: Science Highlights, by (name redacted).

11

Natural climate cycles and forcings, such as volcanoes, will continue; the combined natural and human-induced

changes may result in stable or declining observed temperatures for some periods, as projected by some through 2015,

likely followed by more rapid increases due to the natural cyclic increase plus the GHG-induced increase.

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temperature increases around 2.5 to 3.2oC (4.5 to 5.8o F) by 2100. There is a small but not trivial

likelihood that the GHG-induced temperature rise may exceed 5oC (9o F) above natural variability

by 2100. In context, the global average temperature is estimated currently to be approaching or

exceeding the highest level experienced since the emergence of human civilizations.

Future climate change may advance smoothly or sporadically, and some regions are likely to

experience more fluctuations in temperature, precipitation, and frequency or intensity of extreme

events than others. Almost all regions are expected to experience warming; some are projected to

become warmer and wetter, while others would become warmer and drier. Sea levels could rise

between 7 and 23 inches by 2100, not including the effects of possible accelerated melting of the

Greenland or Antarctic ice sheets. Patterns consistent among different models have led to some

common expectations: GHG-induced climate change would include more heat waves and

droughts; decreased extreme cold episodes; and increased summer warming and dryness in the

central portions of continents. Scientists also expect precipitation to become more intense when it

occurs, thereby increasing runoff and flooding risks. 12

Potential Impacts of Projected Climate Change

A wide band of uncertainty surrounds projections of impacts, and in particular, critical thresholds

for non-linear or abrupt effects. Some impacts of climate change are expected to be beneficial in

some locations with a few degrees of warming (e.g., increased agricultural productivity in some

regions, less need for space heating, opening of the Northwest Passage for shipping and resource

exploitation). Most impacts are expected to be adverse (e.g., lower agricultural productivity in

many regions, drought, rising sea levels, spread of disease vectors, greater needs for cooling).

Risks of abrupt, surprising climate changes, with accompanying dislocations, are expected to

increase as global average temperature increases, and could push natural and socio-economic

systems past key thresholds of tolerance.

Some populations will have the resources to migrate and adapt successfully—even profit from

new opportunities that will emerge—while others could lose livelihoods or lives. Adaptations can

help mitigate impacts and damage costs, but also impose costs, often on those who can least

afford them. Because climate change will occur with different magnitudes and characteristics in

different regions, resulting dislocations and disparities across locations may have implications for

political stability and security.

Some experts and stakeholders believe that likely ecological disruptions are among the most

compelling reasons that humans must act to reduce their interference with the climate system. As

the degree and distribution of climate changes continue, ranges of species are likely to change.

Climate change is highly likely to create substantial changes in ecological systems and services in

some locations, and may lead to ecological surprises. The disappearance of some types of

regional environments also raises risks of extinctions of species, especially those with narrow

geographic or climatic distributions, and where existing ecological communities disintegrate. One

study13 projects that, under a high climate change scenario, 12% to 39% of the Earth’s land areas

12

Kevin E. Trenberth et al., “The Changing Character of Precipitation,” Bulletin of the American Meteorological

Society (September 2003), p. 1205.

13

John W. Williams, Stephen T Jackson, and John E. Kutzbach, “Projected distributions of novel and disappearing

climates by 2100 AD,” Proceedings of the National Academy of Sciences of the United States of America 104, no. 14

(April 3, 2007).

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may experience climates not found at present, while 10% to 48% of land areas’ existing climates

may disappear from the Earth by 2100. In the low climate change scenarios, 4% to 20% of land

areas experience new climates and 4% to 20% see existing climates disappear. The researchers

concluded, “[t]here is a close correspondence between regions with globally disappearing

climates and previously identified biodiversity hotspots; for these regions, standard conservation

solutions (e.g., assisted migration and networked reserves) may be insufficient to preserve

biodiversity.”

Many different views exist regarding how much concern to give to ecological impacts:14 some

people value the impacts only according to the services that natural systems provide to humans

(for example, for recreational activities or provision of food); other people emphasize ethical

perspectives, for example, for stewardship of the Earth’s resources. Likewise, some people

emphasize the relatively mild impacts possible for the United States,15 while others give weight to

the catastrophic impacts likely for at least some populations in other countries. Such differences

in values are behind many of the controversies in the public debates about how to address climate

change, and what part of the global effort the United States should undertake.

Growing attention to impacts and possible adaptations has led, in the 110th Congress, to proposals

in a number of bills that would increase research and programmatic attention on possible impacts

of climate change and options for adaptation. Some bills are cross-sectoral, including some that

propose to repeal and replace the Global Change Research Act of 1990; others are targeted to

specific concerns, such as drinking water or wildlife. Some proposals are aimed at increasing

research on impacts and adaptation, while others are intended to provide authority and resources

to plan and carry out specific adaptations in selected sectors.

Proposed Greenhouse Gas Concentration Targets

The wide range of uncertainty regarding how much GHG emissions may rise, how much the

climate may change, and how risky those changes may be (and how they are distributed among

different populations) results in a broad spectrum of views regarding whether and how deeply to

reduce GHG emissions.

To limit future risks, many experts propose targets to cap or “stabilize” the concentrations of

GHGs in the atmosphere; any level of stabilization is associated with a wide range of possible

temperature outcomes. Current CO2 concentrations are over 380 parts per million (ppm); future

projections in the absence of changes from current policies range from about 550 ppm to almost

1000 ppm by 2100. Most debate concerning the appropriate level at which to stabilize GHG

concentrations is around levels of 450, 550 or 650 ppm of CO2 or CO2-equivalents16 by 2100.

Some people advocate targets of 350 ppm CO2e or lower (less than current concentrations), while

others oppose setting stabilization targets altogether. Preferences for alternative targets are

14

See also CRS Report 98-738, Global Climate Change: Three Policy Perspectives, by (name redacted) and (name

redacted).

15

See discussion later of projected costs of climate change to the United States. While highly uncertain, projected

climate change could have relatively mild impacts on the United States in aggregate, although some regions and

populations will be more adversely affected than others; some populations may benefit from climate change.

16

“Carbon dioxide equivalents,” (CO2e) is an aggregate of all GHG with each gas weighted by its effect on climate

change compared to CO2. CO2 has a value of 1 in the weighting scheme.

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partially explained by differing views of how great the adverse impacts of climate change would

be, associated with different stabilization targets, and differing views of how to address risks.17

The “Stern Report,” discussed further in the economics sections below, concluded that,

[s]tabilising [atmospheric concentrations] at or below 550 ppm CO2e would require global

emissions to peak in the next 10 - 20 years, and then fall at a rate of at least 1 - 3% per

year.... By 2050, global emissions would need to be around 25% below current levels. These

cuts will have to be made in the context of a world economy in 2050 that may be 3 - 4 times

larger than today - so emissions per unit of GDP would need to be just one quarter of current

levels by 2050. To stabilise at 450 ppm CO2e, without overshooting, global emissions would

need to peak in the next 10 years and then fall at more than 5% per year, reaching 70%

below current levels by 2050.18

While technologies exist today to begin such a trajectory, the target would require development

and deployment of new technologies over the longer term.

Program Design and the Costs of GHG Mitigation

Greenhouse gas control programs raise concerns about costs: that the costs may be large; that the

costs of mitigation may exceed the benefits of mitigation; or, that the distribution of costs may not

be “fair.” Many studies show that costs would be influenced by the

•

stringency of the reductions,

•

timing of its reductions, and

•

flexibility allowed by the program design.

Designing “flexibility” in a GHG mitigation program (e.g., allowing trading of emission permits;

generation by non-covered sources of emission reduction credits or “offsets” against

allowances;19 banking or borrowing of permits; etc.) can significantly lower costs, according to

economic modeling.20

Modeled estimates of costs for a given GHG reduction program typically vary because of

differences in the models used; and methods and assumptions, regarding, among other factors:

•

economic and energy growth rates without policies;

•

future energy resource availability and prices;

•

availability, efficiencies and costs of technologies;

17

Views on appropriate targets may also be partially explained by different perceptions of the challenges and costs of

reducing GHG emissions.

18

Stern, Nicholas. The Economics of Climate Change. Stern Review Report. London: HM Treasury, October 30, 2006.

http://www.hm-treasury.gov.uk/independent_reviews/stern_review_economics_climate_change/

stern_review_report.cfm. Executive Summary, p. xi.

19

See CRS Report RL34436, The Role of Offsets in a Greenhouse Gas Emissions Cap-and-Trade Program:

Potential Benefits and Concerns, by (name redacted).

20

See CRS Report RL33799, Climate Change: Design Approaches for a Greenhouse Gas Reduction Program, by

(name redacted).

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•

specific assumptions about program design (such as the scope of emission

trading or offsets allowed; whether emission permits are given or auctioned; uses

of any revenues, etc.);

•

responsiveness of people’s choices and technology development to policy

incentives; and

•

the scope of costs and “co-benefits” counted in the analysis.

Some but not all differences among results represent irreducible uncertainties; specification (e.g.,

of program design) and study of appropriate assumptions can allow one to build more confidence

in some estimates than others. Many insights may be gained from the sensitivity analyses

provided, which illustrate how costs and distributional impacts may vary with alternative

judgments regarding the future and the specific program designs. Studies indicate that mitigation

and adaptation efforts could also support other policy objectives (“co-benefits”), such as

improving energy security and reducing health costs of pollution. Such co-benefits are discussed

in a later section.

Distributional Impacts of Programs

Critical to many policy makers in GHG mitigation and design of program are the distributions of

costs on specific industry sectors and employment groups, U.S. regions, and income groups. One

particularly challenging issue is how to address concerns regarding possible harm to trade and

competitiveness of those countries and industries that shoulder the responsibilities of GHG

reductions. To the degree that those industries (or companies within industries) increase their

costs with mitigation measures, they may experience a price disadvantage in relation to

competitors without GHG requirements or competitors that are advantaged by GHG regulation

(for example, sources that have positioned themselves to reduce emissions at lower costs than

their competitors).

Other groups that are likely to be disproportionately impacted by policies to limit GHG emissions

include low income populations, which typically spend more of their incomes on energy bills, and

may not have choices or control over factors that determine their energy dependence (such as

renters). Alternatively, some groups may gain disproportionately from GHG controls. For

example, manufacturers that specialize in high-efficiency vehicles would experience different

costs, market share, and profitability than manufacturers that specialize in high-powered vehicles.

Some groups may benefit from certain policy designs, for example, depending on whether

existing GHG emitters are given (rather than sold) their emission permits (“allowances”). These

“equity” issues may drive policy design, and could make the emerging policy overall more costly,

but with more acceptable distributional effects.

Climate Change and Other Policy Issues: Commonality or Conflict?

Because GHG emissions are related to so many sectors, climate change policy inevitably affects

other national policy objectives, such as public well-being, reliable energy services, affordable

food supply, and prudent management of natural resources. Many technologies and policy options

can serve all or many policy objectives. For example, economical investment in energy efficiency

can support all the goals above. Other options, such as promoting ethanol production from corn,

may involve difficult trade-offs. Cross-issue analysis can help to maximize win-win choices and

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avoid conflicts, but may be under-utilized due to lack of resources, disciplinary or jurisdictional

obstacles, or uneven input into policy processes.

U.S. Costs of GHG Mitigation

Analyses by the Energy Information Administration (EIA) and the Environmental Protection

Agency (EPA) suggest that efficiently designed GHG reduction legislation could reduce U.S.

GHG emissions from the reference case by about one-quarter by 2030, at a cost of roughly 0.3%

to 3.8% of the business-as-usual Gross Domestic Product (GDP), with half the modeled cases at

1% of GDP or less. Technically and politically, though, an “efficiently designed” program may

not be realistic. CRS analysis (Parker and Yacobucci)21 found from various studies that the

uncertainties about the future reference (“business-as-usual”) cases for incomes per capita were

greater than the impact on them by the GHG mitigation proposed by the 110th Congress’ S. 2191

(now S. 3036), the “Lieberman-Warner” bill. (This bill was reported out of the Senate Committee

on Environment and Public Works in 2007 and proceeded to debate by the Senate in June 2008.).

Beliefs about the effectiveness of measures in S. 2191 (S. 3036) to stimulate technological

advance are an important difference among several cost analyses of the bill. Parker and Yacobucci

found that:

In its analysis, [Clean Air Task Force] CATF expresses confidence in S. 2191’s various

technology and efficiency provisions and models the bill assuming EIA’s Best Available

Technology (BAT) case, banking, and offsets. In contrast, [the American Council for Capital

Formation/National Association of Manufacturers] ACCF/NAM states that it is “unlikely”

that technology, new energy sources, and market mechanisms (e.g., carbon offsets, banking)

will be sufficiently available to achieve S. 2191’s emission targets. Accordingly,

ACCF/NAM’s assumptions differ substantially from CATF’s and other studies by excluding

banking, significantly capping the availability of various technologies, and assuming higher

construction costs.

This difference was among the main reasons that the CATF produced a cost estimate at -0.9% (a

reduction) of Gross Domestic Product per capita in 2030, compared to the ACCF/NAM’s -2.6%

to -2.7%.22

Regarding the effects of S. 2191 (S. 3036) on international trade and the possible movement

abroad of manufacturing (and its emissions, termed “leakage”), the Environmental Protection

Agency provided the only analysis to date: it found no “leakage” if currently developing countries

were to undertake action to maintain their 2015 GHG emission levels beginning in 2025, and to

return their GHG emissions to 2000 levels by 2050. In a worst case scenario, EPA’s analysis of a

no-international-actions-to-2050 scenario projected that developing countries’ projected GHG

emissions would be about 1% higher, equivalent to U.S. emission leakage rates of approximately

11% in 2030 and 8% in 2050.23 U.S. exports were projected to decline, but imports might increase

or decrease, depending on assumptions.

21

See CRS Report RL34489, Climate Change: Costs and Benefits of S. 2191/S. 3036, by (name redacted) and (name red

acted).

22

Ibid, p. 29. Reduction is relative to the same model’s reference case baseline for 2030.

23

EPA, EPA Analysis of the Lieberman-Warner Climate Security Act of 2008: S. 2191 in 110th Congress (March 14,

2008) p. 84.

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Global Costs of GHG Mitigation

The Intergovernmental Panel on Climate Change (IPCC), in its Fourth Assessment Report (2007),

found that most economic analyses indicate that policies aiming to stabilize GHG concentrations

in the atmosphere at 590 to 710 parts per million (ppm) of CO2-equivalent could incur small

aggregate costs—or possibly some gains—to economic growth. Achieving the lowest

concentrations analyzed (e.g., 450 ppm) could dampen growth, with 90% of the studies indicating

costs less than 3% of cumulative Gross World Product projected for 2010 to 2030, or less than

0.12 percentage points of the average annual growth rate. While the IPCC represents the

consensus of a wide range of experts and governments, some other experts question its findings

and conclusions.

Policy choices would determine how the costs, or changes in growth, would be distributed across

and within regions internationally. In addition, adaptation efforts are considered necessary

because of climate changes occurring now and likely in the future that are attributed to past GHG

emissions. Though adaptation costs typically are not factored adequately into economic analyses,

the effects on economies and non-market processes of climate change policies will reflect both

the costs of mitigation, the costs of adaptation, and residual damages or benefits.

Benefits of Mitigating Climate Change

Inadequate Data, Tools, and Understanding of Impacts

Many people implicitly wish to compare the benefits of proposed action24 with the costs of that

action; however, data and appropriate tools are inadequate to compare reliably and quantitatively

the benefits and costs of abating climate change. Benefits analysis has received relatively little

attention in the United States, with most analyses coming from other countries. A number of

studies have attempted to estimate the benefits of mitigating GHG emissions, with a wide range

of partial estimates. More rare are the few studies that integrate both mitigation and impacts of

climate change, though the likely interaction between them is well recognized in the research

community.25

No studies of benefits are comprehensive: all omit some sectors and types of impacts; all face

challenges in quantifying and monetizing non-market effects; all require applying assumed

(typically monetary) values to disparate nations and people potentially affected; and most do not

address “multiplier effects”26 or variability and uncertainties in their methods. Further, the most

commonly used metric of impacts is change in Gross Domestic Product or Gross World Product,

although these are poor measures of the well-being of people and the world’s natural systems.

24

The benefits of policies to reduce climate change are not the same as the damages that could be caused by climate

changes without the policy. In particular, some amount of climate change will occur no matter how quickly policies

strive to reduce emissions; this would make benefits smaller than the future costs of climate change. In addition, there

may be co-benefits or secondary costs of policies that may increase or decrease benefits of a policy.

25

For example, climate change is expected to alter vegetation patterns, the transition of which would affect efforts to

sequester carbon in soils and vegetation. Or, it may reduce demand for heating, potentially reducing benefits of

improving heating efficiency.

26

“Multiplier effects” here refers to the secondary and follow-on impacts of climate changes, as computable general

equilibrium (CGE) models do for mitigation cost analyses.

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Moreover, the capability does not exist to assess all the nuanced and interacting ramifications of a

changing climate. For example, although adverse climate change in many developing countries

could exacerbate political instabilities and increase threats to U.S. security, calculating the

magnitude and timing of added security risks—and the value of lessening them—would be

guesswork. Furthermore, because many projections place the Earth’s future climate into a range

never experienced by human civilizations, observational evidence from the past is helpful but

inherently not analogous to what may evolve; much will remain unknown no matter how much is

invested in research. On the other hand, many flaws in current benefits analyses could be

overcome with more study and improved analysis, and explicit methods for taking uncertainties

into account (with value judgments) for more robust decision-making.

Global Costs of Climate Change

Almost all economists conclude that, while climate change in the near-term could have globally

aggregated net benefits, further climate change would tend to decrease benefits while damages

would increase. In net, they conclude that long-term climate change is likely to damage economic

growth worldwide and incur cumulative costs that could reach many trillions of dollars.

The Costs of Climate Change Are Not the Same as the Benefits of Mitigation

Most studies estimate the potential costs of climate change, not the benefits—the costs of climate change that could

be avoided by specific mitigation policies. However, mitigation policies are unlikely to avoid all future, GHG-induced

climate change or its impacts. Therefore, the benefits of mitigation policies (i.e., the avoided impact costs) are likely to

be less than the total costs of climate change impacts.

Benefits of Mitigation + Unavoided Damages = Total Costs of Climate Change

(This simplification ignores, however, that policies might be designed to garner benefits to other social objectives,

such as improving energy security or avoiding deaths from air pollution.) Thus, attention to this difference may be

warranted by people who wish to compare the costs and benefits of a proposed policy.

Nonetheless, most economists who have modeled both mitigation costs and its benefits conclude

that well designed policies could have modest costs and save trillions of dollars over the coming

century. Most economists would agree that the long-term costs of climate change merit some

degree of near-term and mandatory action to reduce GHGs. However, beyond those general

points, there is a wide range of views and controversies.

The most comprehensive and rigorous review of the benefits of mitigating climate change is the

“Stern Report,” commissioned by the Government of the United Kingdom and released in 2006.27

The Stern Report has been strongly criticized by some notable economists, due to differences of

views over methodological challenges, as well as to allegations of selectiveness of studies used.

Other equally reputable economists have indicated their acceptance of the methods and/or

provided analysis contending that the Stern estimates of possible climate change costs may be

27

Stern, Nicholas. The Economics of Climate Change. Stern Review Report. London: HM Treasury, October 30, 2006.

http://www.hm-treasury.gov.uk/independent_reviews/stern_review_economics_climate_change/

stern_review_report.cfm.

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low. In brief, the Stern Report underscores that climate change policy must involve value-laden

choices by public decision-makers.28 In support of this, the Stern Report laid out a hierarchy of

different valuation choices, leading to estimates of climate change damages ranging from 0 to

20% or more of global consumption “now and in the future.”

Potential Costs of Climate Change to the U.S. Economy

Several studies of the potential costs (or benefits) to the United States of projected GHG-induced

climate change have been conducted, though none is comprehensive and all suffer from the

general challenges of applying economic and ethical methods to the issue. A recent review of

economic studies of impacts in the United States by the University of Maryland’s Center for

Integrative Environmental Research stated the following “Five Key Lessons,” which reflect

commonly held views among climate impacts researchers:

•

Economic impacts of climate change will occur throughout the country.

•

Economic impacts will be unevenly distributed across regions and within the

economy and society.

•

Negative climate impacts will outweigh benefits for most sectors that provide

essential goods and services to society.

•

Climate change impacts will place immense strains on public sector budgets.

•

Secondary effects of climate impacts can include higher prices, reduced income,

and job losses. 29

The report cites a variety of regional studies that project costs of climate change impacts to

localities or sectors in the tens of millions to hundreds of billions of dollars through the 21st

Century. The report also concludes, “[t]here is, however, a lack of research that quantifies and

compares these impacts, and a deficiency in using what is known about climate impacts to guide

adaptation actions from the national level down to the local level. Thus, the full economic costs

will likely be much higher than what is reported currently.”

Few studies have attempted to aggregate the economic costs of climate change to the United

States across sectors in the absence of effective mitigation policies, and all of those studies

qualify their results by recognizing the uncertainty and methodological questions. One such study,

by economist Dale Jorgenson30 and others, which examined a wide range of possible projections

of climate change, though only market effects, concluded:

28

Examples of choices more appropriately addressed by policy makers than researchers include how to value impacts

on current versus future generations; whether to give weight to impacts on particular populations, such as low-income

populations or children; whether certain adverse impacts are not acceptable and might lead to maximum allowable

degrees of change; etc.

29

Ruth, Mathias, Dana Coehlo, and Daria Karetnikov. The US Economic Impacts of Climate Change and the Costs of

Inaction. Center for Integrative Environmental Research, University of Maryland, October 2007.

http://www.cier.umd.edu/climateadaptation/.

30

Jorgenson, Dale W, Richard J. Goettle, Brian H. Hurd, and Joel B. Smith. U.S. Market Consequences of Climate

Change. Prepared for the Pew Center on Global Climate Change. Arlington, VA, April 2004.

http://www.pewclimate.org/global-warming-in-depth/all_reports/marketconsequences.

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Based on the market sectors and range of impacts considered for this analysis, projected

climate change has the potential to impose considerable costs or produce temporary benefits

for the U.S. economy over the 21st century, depending on the extent to which pessimistic or

optimistic outcomes prevail. Under pessimistic assumptions, real U.S. GDP in the low

climate change scenario is 0.6 percent lower in 2100 relative to a baseline that assumes no

change in climate; in the high climate change scenario, the predicted reduction in real GDP is

1.9 percent [lower in 2100]. Under the additional “high and drier” climate scenario, however,

real GDP is reduced more dramatically—by as much as 3.0 percent by 2100 relative to

baseline conditions. Furthermore, under pessimistic assumptions negative impacts on GDP

grow progressively larger over time, regardless of the climate scenario. In contrast, under

optimistic assumptions real U.S. GDP by 2100 is 0.7 to 1.0 percent higher than baseline

conditions across the low, central and high climate scenarios, but these benefits eventually

diminish over time. Nevertheless, to the extent that responses in certain key sectors conform

to the optimistic scenarios, there is a distinct possibility that some degree of climate change

can provide modest overall benefits to the U.S. economy during the 21st century.

Many studies underscore a key point: the impacts of climate change on people and on

ecosystems, and the benefits or damages, will depend heavily on the ability to adapt by different

populations and systems, and the effectiveness of actions to adapt. Concerns about climate

change, consequently, often emphasize the vulnerabilities of populations with low financial and

technical resources, or that may be otherwise constrained in their adaptations (e.g., native cultures

that are dependent on, and value, a habitat that may be eliminated by climate change, as in some

Arctic populations).

“Co-Benefits” and Trade-offs of GHG Mitigation

Adding to the benefits of GHG mitigation would be many measures that would help to avoid

climate change and would serve other national goals, such as improving energy security, abating

the world food crisis, reducing pollution, and conserving critical natural resources and

biodiversity. For example, actions to suppress demand for petroleum would help suppress global

oil prices and total U.S. expenditures for energy. Such “co-benefits” of GHG mitigation would

boost the value of abating climate change.

Offsetting the benefits would also be some trade-offs with other national or local goals, although

many trade-offs could be minimized or eliminated through policy design that is mindful of the

relationships among issues. For example, incentives to reduce GHG emissions by increasing

biofuel use could raise food prices31 and reduce food security, or could enhance food security by

selectively encouraging feedstocks that do not compete for agricultural land and key

commodities, and by improving agricultural efficiencies.32

31

Food prices are influenced by a variety of factors; the influence of biofuels production on commodity and food prices

is summarized in, for example, Joseph Glauber, Statement of Joseph Glauber, Chief Economist, Before the Committee

on Energy and Natural Resources,United States Senate (Washington DC, 12 June 2008); or, Economic Report of the

President (Washington DC: Council of Economic Advisors, January 2009), p. 50, [www.nber.org/erp/2009_erp.pdf].

wds.worldbank.org/servlet/WDSContentServer/WDSP/IB/2008/07/28/000020439_20080728103002/

Rendered/PDF/WP4682.pdf].

See also CRS Report R40155, Selected Issues Related to an Expansion of the Renewable Fuel Standard (RFS), by

(name redacted) and (name redacted).

32

For options relating to biofuels production, see, for example, Nellemann et al., eds., The Environmental Food

Crisis—The Environment’s Role in Averting Future Food Crises (Norway: United Nations Environment Programme

(UNEP), 2009), http://www.grida.no/publications/rr/food-crisis/ebook.aspx.

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Importance of the Distribution of Losses (or Gains)

Experts agree that climate change, in the near term, will create both those who gain (e.g.,

agricultural producers in cool to moderate and wet climates) and those who will suffer (e.g.,

agricultural producers in hot and dry climates). Some people are likely to experience slow and

moderate changes, while others are likely to experience such radical changes in their climate that

their current way of life—and possibly their locales—becomes unsustainable. Some people will

have the resources to migrate and adapt successfully—even profit from new opportunities that

will emerge—while others could lose livelihoods or lives. The same would be true also with

policies to mitigate GHG emissions (e.g., the potential effects on coal producers).

Embodied in any debate over climate change and what to do about it are the potential inequities

of policies to mitigate or not to mitigate climate change. Despite these distributional hazards

being fundamental to the debate, they are among the least researched of all climate change issues.

Part Two: The International and Domestic Policy

Fields

The stage for upcoming policy deliberations is set by the existing frameworks internationally and

domestically. The developing countries now contribute the major, and most rapidly increasing,

share of GHG emissions globally.33 Effectively abating climate change would require GHG

reductions in all major countries. Additionally, some industries fear adverse trade impacts if their

competitors in other countries do not have similar requirements to reduce GHG emissions. In the

United States, these issues, along with concerns about U.S. leadership and sovereignty, figure into

the debate over long-term GHG concentration targets and near-term emission controls.

Legislative actions would be superimposed on existing federal programs and a patchwork of state

and local policies to reduce a part of U.S. GHG emissions. One legislative challenge would be to

create a coherent strategy from the current components.

Status of International Cooperation on Climate Change34

The United Nations Framework Convention on Climate Change

Internationally, 192 countries—including the United States—joined the 1992 United Nations

Framework Convention on Climate Change (UNFCCC) to stabilize “greenhouse gas

concentrations in the atmosphere at a level that would prevent dangerous anthropogenic

interference with the climate system” (Art. 2). Although science can help to identify the degree of

“interference” and implications of climate changes at different concentration levels or degrees of

temperature change, most scientists agree that the determination of “dangerous” is a political

decision, not one that can be objectively decided by scientists.

33

Calculated from estimates for 2005 in International Energy Agency, CO2 Emissions from Fuel Combustion 19712005, 2007, online database. Data extracted May 30, 2008.

34

See CRS Report RL33826, Climate Change: The Kyoto Protocol, Bali “Action Plan,” and International Actions, by

(name redacted).

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The Kyoto Protocol

Agreeing that mandatory GHG reductions would be necessary to avoid “dangerous anthropogenic

interference,” most countries in 1997 signed the Kyoto Protocol. It sets legally binding GHG

targets—an average 5% reduction below 1990 emissions levels during the period 2008-2012—for

38 industrialized countries. The Kyoto Protocol has been ratified by 175 countries, including 37

of the 38 industrialized countries.

The United States Rejected the Kyoto Protocol

The United States signed the Kyoto Protocol in 2007. However, President Bush in 2001

announced that the United States would not become a Party to the Kyoto Protocol.35 His principal

arguments against it were (1) uncertainty of the science; (2) potentially high cost of GHG

abatement programs; and (3) lack of GHG abatement commitments from developing countries.

President Bush announced a U.S. policy to reduce the “greenhouse gas intensity” (ratio of

emissions to economic output) of the U.S. economy by 18% from 2002 to 2012. This target

represented up to a four percentage point increase above previous trends.

“Common but Differentiated Responsibilities”

Both the UNFCCC and the Kyoto Protocol operate under the principal of “common but

differentiated responsibilities.” Effective efforts would need to be made by all large emitting

nations in order to stabilize global GHG concentrations. Nations’ views diverge concerning the

Kyoto Protocol and “post-Kyoto” steps (post-2012): industrialized nations fear harm to their

economic competitiveness if developing countries do not also limit emissions; developing

nations, a growing source of emissions, typically argue that industrialized countries have emitted

most GHGs historically and can better afford to reduce emissions first and deeper. They argue

that low-income nations must give first priority to alleviating poverty. The UNFCCC embodies

the principle of “common but differentiated responsibilities” to reflect the agreement that each

nation must contribute to addressing climate change, but that its priorities and the magnitude of

its efforts should differ according to national circumstances. The differences of views concerning

appropriate common responsibilities and differentiation are at the core of the international

negotiations.

The Bali Action Plan

To negotiate the next round of international commitments, Parties to the UNFCCC agreed to the

“Bali Action Plan” in December 2007. The Bali Action Plan established an Ad Hoc Working

Group on Long-term Cooperative Action under the UNFCCC to complete and present its work to

the 15th meeting of the Parties, in November-December 2009. The first session of the Ad Hoc

Working Group met in April 2008. In parallel to the UNFCCC process, President Bush

announced in May 2007 that the United States would convene a series of meetings of major

economies (MEM) to develop a post-2012 framework to address climate change. To the “MEM”

process, President Bush proposed a multilateral “clean technology fund” totaling $3 billion to

stimulate international investments in clean energy and adaptations to climate change. His

35

Neither President Clinton nor President Bush sent the Kyoto Protocol to the Senate for ratification.

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FY2009 budget requests a first U.S. payment of $400 million to this fund. Japan has proposed a

similar multilateral fund of $10 billion.

Current Domestic Policy on Climate Change

Goal

On April 16, 2008, President George W. Bush announced a new national goal for climate

policy—to halt increases in U.S. emissions of GHGs by 2025.36 Emissions would begin to decline

thereafter “so long as technology continues to advance.”37 According to the President, the United

States would achieve this goal by regulatory measures and market incentives to encourage use of

clean technologies. President Bush said that the United States would be willing to include this

plan in a future international agreement as long as all other major emitting economies also

include their plans in the agreement. Some stakeholders have criticized the new Bush policy for

proposing any cap on future emissions, while others have criticized it as too little, too late.

Federal Policies

Current federal climate change policies provide incentives, but few requirements, to reduce GHG

emissions. For example, a number of tax incentives are in place to encourage purchase of more

efficient vehicles and to make efficiency improvements to buildings. Other incentives induce

agricultural producers to enhance soil carbon. A suite of federal programs provides information,

technical assistance and nominal awards to businesses, universities and other consumers to

quantify and reduce their GHG emissions; such programs generally are intended to encourage

emission reductions that are already economical but that do not occur because of market

inefficiencies. Some GHG reductions are also achieved by existing regulations governing the

energy efficiency of vehicles and appliances, methane emissions from landfills, and other

controls. Again, these regulations have been put in place for reasons other than abating climate

change. Large programs are devoted to developing new technologies that would be necessary to

reduce GHG emissions below current levels. Many experts contend that voluntary efforts (such as

the U.S. Climate Leaders Program), research on technologies, and existing regulatory and tax

incentives cannot achieve the GHG reductions necessary to avoid “dangerous” climate change.

The United States and the European Union have proposed, for the Doha Round of the World

Trade Organization (WTO) negotiations, a New Environmental Goods and Services Agreement

(EGSA) to eliminate tariff and non-tariff barriers to environmental technologies and services. The

proposal aims particularly at lowering the cost and increasing access to “clean energy”

technologies.38

36

This is not the first quantitative GHG goal set for U.S. climate change policy: on April 21, 1993, President William J.

Clinton “announce[d] our nation’s commitment to reducing our emissions of greenhouse gases to their 1990 levels by

the year 2000,” consistent with the Article 4 aim of the UNFCCC. The challenge in meeting that aim with voluntary

measures only led to agreement on mandatory GHG reduction obligations in the Kyoto Protocol.

37

White House. Fact Sheet: Taking Additional Action to Confront Climate Change. Press Release, April 16, 2008.

http://www.whitehouse.gov/news/releases/2008/04/print/20080416-7.html.

38

U.S. Mission to the European Union. “U.S., EU Announce New Climate Initiatives for WTO.”

http://useu.usmission.gov/Dossiers/Environment/Nov3007_USTR_Environment.asp.

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Funding39

Of the $6.4 billion in U.S. federal funding in FY2008 for climate change activities, almost all is

for scientific and technological research and development. In addition, tax incentives that could

help to reduce GHG emissions are forecast to reduce federal revenues by about $1.5 billion in

FY2008. Funding for regulatory, voluntary and public education programs is a few percent of the

total.

Legislative Actions

The Congress faces increasing pressure from the public to address the risks of climate change;

avoid creating a patchwork of state and local requirements; provide certainty for investors in U.S.

systems; and position the United States for competitiveness in the growing world markets for

“clean” energy. In the 110th Congress, Members have introduced numerous bills to address

various aspects of climate change.40 These bills cover a wide spectrum, ranging from climate

change research to GHG emissions cap-and-trade programs or emissions taxes. Additional bills

focus on GHG reporting or registration. Several bills would authorize planning and carrying out

of adaptations to expected climate change in specific sectors, nation-wide or internationally.

Annual appropriations for climate change programs directly affect the federal level of effort for

authorized activities.

As of the date of this report, the 110th Congress has enacted two broad pieces of legislation—an

omnibus energy bill (P.L. 110-140) and a comprehensive appropriations act (P.L. 110-161)—that

include climate change provisions. Both statutes increase climate change research efforts, and the

energy act requires improvement in vehicle fuel economies, as well as other provisions that

would reduce (or sometimes increase) GHG emissions. P.L. 110-161 directs the Environmental

Protection Agency (EPA) to develop regulations that establish a mandatory GHG reporting

program that applies “above appropriate thresholds in all sectors of the economy.” In addition, in

December 2007, the Senate Committee on Environment and Public Works approved a bill, S.

2191 (now S. 3036)—the “Lieberman-Warner” bill, that would require “economy-wide” GHG

reductions. This bill is scheduled to go to the Senate for consideration in June 2008.

Regional, State, and Local GHG Policies41

In the absence of a federal regulatory framework to address U.S. GHG emission reductions, a

majority of states have established formal GHG mitigation policies, including targets for future

reductions. California, Hawaii, and New Jersey have passed laws establishing mandatory,

economy-wide GHG emission limits, while a number of additional states have set controls on

CO2 emissions from particular sources. In several regions, including the Northeast, the Midwest

and the West, states are working together to create regional schemes to cap GHG emissions and

allow trading of emissions permits across borders. The increasingly complicated mosaic of state,

39

See CRS Report RL33817, Climate Change: Federal Program Funding and Tax Incentives, by (name redacted).

40

See CRS Report RL34067, Climate Change Legislation in the 110th Congress, by (name redacted) and (name red

acted).

41

See CRS Report RL33812, Climate Change: Action by States to Address Greenhouse Gas Emissions, by (name redact

ed).

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local, and regional GHG initiatives may place growing pressure on the federal government to

establish a coherent national regulatory strategy to address GHG emissions.

Climate Change Litigation

A proliferation over the past five years of litigation relating to climate change may also press the

federal government toward actions to reduce GHG emissions. For example, the Supreme Court

ruled in 2007 that the EPA must consider regulating CO2 and other GHGs emitted from motor

vehicles as pollutants under the Clean Air Act.42 Further litigation has been pursued, to challenge

the Executive Branch to action, using the Endangered Species Act, the Energy Policy and

Conservation Act and the Outer Continental Shelf Lands Act. A few international-law claims have

been filed against the United States as well.43 However,

[w]hether these new paths will yield results, only time will tell. It is clear, however, that if

there is to be a government response to climate change at all, a solution from the political

branches is more likely to be comprehensive and fully reflective of societal priorities than the

typically narrowly targeted results of litigation.44

Part Three: The Policy Tool Box

With growing consensus on climate change science and pressures from interest groups, many

legislators are deliberating whether and how to address climate change. Some may prefer to

continue to employ the existing set of research and voluntary programs. Available for others who

are considering additional actions is an assortment of policy tools that they see as stimulating

further reductions of GHG emissions and reducing risks to the economy, specific populations, and

natural systems. Part Three of this report identifies a variety of policy tools potentially affecting

these objectives:

•

regulatory, including market-based, tools to reduce GHGs;

•

distribution of potential revenues from GHG programs;

•

non-regulatory tools that help markets work more efficiently;

•

tools to stimulate technological change;

•

options to ease the economic transition to a lower GHG economy;

•

instruments to encourage international actions; and

•

tools to stimulate adaptation to climate change.

The following sections summarize some potentially applicable instruments in each of these

categories that have been proposed or used in the past. Many of these tools are complementary,

and proponents often contend that they would produce results more efficiently when carefully

matched than any one alone.

42

Massachusetts v. EPA, 127 S. Ct. 1438 (2007).

See CRS Report RL32764, Climate Change Litigation: A Survey, by (name redacted).

44

Ibid., p.35.

43

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Regulatory and Market Tools to Reduce Greenhouse Gases

Most experts agree that the most economically efficient way to reduce GHG emissions

substantially is to put a price on emissions that reflects the costs (or risks) of those emissions to

others. Putting a price on GHG emissions can be done with traditional source-by-source

regulation, and/or with “market mechanisms.”

Source-by-Source Regulations

From the earliest decades of air pollution controls, emission reductions have been achieved by

setting emission performance standards on each source of pollution, or requiring that sources use

a particular type of technology, such as the “best available control technology”; practice has

successfully included “technology-forcing” regulation, as well, that sets future performance

standards well beyond contemporaneously achievable levels. Regulatory controls have proven to

be effective through decades of experience, though studies have demonstrated that the compliance

costs might have been reduced if strategies had given priority to cost-effectiveness and flexibility.

Even when regulators have been allowed by law to consider costs in setting emission regulations,

they have had additional factors to consider and often have had weak information about the costs

of technology for each individual source. Also, regulations can be difficult to adjust as

circumstances change. Although in some circumstances source-by-source regulation may be most

effective and efficient, 45 it often cannot achieve, by itself, a desired emission reduction target at

the least possible cost.

Market Mechanisms

Regulatory approaches that utilize aspects of commodity markets can achieve, in some cases,

similar emission reductions but at lower overall cost. Bills introduced in the 110th Congress have

proposed such “market mechanisms” to reduce GHG emissions because, for some sources, they

can increase the efficiency of source-by-source regulation by allowing the least costly reductions

first. Market mechanisms begin with regulations to reduce emissions, but then may allow

flexibility in who makes the emission reduction, when the reductions are made, and where the

emission reductions occur (outside of the regulated sources, or even internationally).

Two principal types of market mechanisms pertinent to GHG reductions are GHG or carbon

taxes, or cap-and-trade systems. The key contrast between these two mechanisms is that

•

GHG taxes would provide certainty about the prices paid by sources, but

uncertainty concerning how much GHGs would be reduced;

•

conversely, cap-and-trade systems provide certainty in how much GHGs would

be reduced, but not regarding the prices paid by sources.

Both emission fees and cap-and-trade systems potentially generate revenues—potentially in the

billions of dollars annually. Issues regarding what to do with revenues will be introduced

following brief discussion of some potentially contentious design issues.

45

In some instances, performance standards can be very efficient, for example, when transaction costs are high

compared to the incremental cost of control.

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GHG Fees or Carbon Taxes

Fees would be charged to a source of emissions according to its total emissions. Theoretically, a

source would reduce its emissions down to the level where it is no longer cheaper to make the

reductions (per ton) than to pay the tax (per ton). There could be many variations on this basic

model, including charging fees only on emissions above rates designated by source types. Aside

from possible tax exemptions, emission fees would not allow flexibility in who or where GHG

reductions would occur. A system might be designed to allow flexibility in when GHG reductions

are made, though the principal flexibility would be the source’s decision whether to make the

reductions or pay the taxes. Many economists believe that emission fees or taxes would be the

most economically efficient way to reduce emissions, though this might depend on microeconomic factors, and it would not guarantee an overall level of effectiveness for the program.

Some people object to paying “taxes” in general, even if it is to correct an acknowledged

problem.

“Cap and Trade”

In a cap-and-trade program, the regulator sets an overall cap on emissions, and must allocate

responsibility for achieving the cap to individual sources, frequently termed “allowances” to emit.

In cap-and-trade programs, the trade component allows entities to sell their unneeded emission

“allowances,” while emission sources that emit more than their allowances may comply by

reducing their emissions and/or buying additional allowances.46 Cap-and-trade programs allow

flexibility in who makes the required emission reductions. Within cap-and-trade systems are two

additional types of flexibility:

•

International credits or offsets: Flexibility in where reductions occur—in the

United States or internationally—can also minimize costs, although some

questions arise about enforceability, loss of program effectiveness, and financial

flows. Allowing international credits or offsets, to the degree that GHGs could be

reduced reliably at lower cost in other countries, could help reduce costs of

complying with U.S. GHG requirements.

•

Banking and borrowing: When flexibility could allow entities to save or “bank”

unneeded allowances until they need them, or to “borrow” against their future

allocations of allowances (with a charge for borrowing). Banking and borrowing

could apply to source-by-source regulation as well as to cap-and-trade programs.

Design Choices in Cap-and-Trade Programs

Although there are numerous questions to resolve in designing a cap-and-trade program,47 such as

the level at which to set the cap, which sources to cover under the cap, whether to allow offsets

from non-covered sources and other countries, etc., this section discusses two: how to allocate the

46

More detailed descriptions of how cap and trade programs may work are discussed in a later section on program

design, and in several CRS reports, including CRS Report RL33799, Climate Change: Design Approaches for a

Greenhouse Gas Reduction Program, by (name redacted), and CRS Report RL33846,

Greenhouse Gas Reduction: Capand-Trade Bills in the 110th Congress, by (name redacted), (name redacted), and (name redacted).

47

Ibid.

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GHG reduction requirements, and whether to set a ceiling or floor on the prices a source must pay

for any allowances it wishes to purchase.

Allocating the GHG Reduction Requirements

Policy makers would have to decide who would be responsible for reducing GHG emissions—

this determines who pays for the reductions, not who actually makes the reductions. In a cap-andtrade system, allowances can be

•

given away (e.g., “grandfathered” to existing GHG sources, or given to nonsource entities),

•

sold at a fixed price,

•

auctioned, or

•

a combination of these techniques.

Allowances are a valuable commodity (because they can be sold). How this valuable commodity

is allocated could potentially transfer billions of dollars of wealth across different groups. This

transfer of wealth (from entities who need to buy allowances, to entities that sell them) could be

many times greater than the economic cost of the GHG reductions. How to allocate allowances is

therefore an important component—and among the most controversial—in the GHG reduction

debate. Giving allowances to particular groups may be a tempting way to increase the

acceptability of a GHG control program, or to improve the “fairness” of the program, but it could

distort incentives and reduce the efficiency of the program. One way (among others) to minimize

the transfer of wealth in a GHG control program would be to sell allowances rather than to give

them away. Sales, including auctions, would increase the efficiency of an overall GHG reduction.

Selling the allowances at a fixed price becomes very much like an emission fee or tax program.

Many proposals would give away some allowances to both sources of emissions and other entities

(e.g., states, other sectors) and would auction some allowances.

“Safety Valves” and Allowance Price Floors

GHG allowances under a cap-and-trade program become a market commodity; the prices of most

commodities rise and fall—sometimes with great volatility—as daily, seasonal or annual

conditions vary. Variance would be expected with GHG allowance prices.

Prices could rise above anticipated levels if reducing GHGs turns out to be more difficult than

projected, or if speculators bid up prices, or under other conditions. Some people concerned about

the costs of GHG reduction programs advocate setting a ceiling on the maximum price a source

might have to pay for allowances it may need to comply; some have termed this a “safety valve”

on prices. If prices were to exceed a designated level for some period of time, either the

regulatory authority could release additional allowances into the market through an auction, or

sales at a fixed fee. While this would limit the overall cost of the program, it would also limit the

overall GHG reductions (although these could be “borrowed” from future years), and it would

reduce incentives for technological innovation: The profits that can be reaped when prices spike

is part of the calculation that stimulates some investors to finance technological research.

Other stakeholders argue that, to stimulate technological advance, a floor should be set on the

prices for allowances in the market (i.e., the regulator set a “reserve price” for allowances sold at

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auction, or would buy allowances in the market until the prices rise to the minimum acceptable

level). While constraining how little the GHG program may cost, a price floor assures investors

there is a minimum value for the services their technologies could provide.

Distributing the Revenues from Taxes or Sales

If emissions are taxed, or allowances are sold to sources at flat fees or by auction, public revenues

could be generated—as much as hundreds of billions of dollars per year (depending on the size of

the tax or the quantity of reductions required). A key policy issue associated with taxes, sales or

auctions is what to do with the revenues. Revenues can be used to

•

offset reductions of other taxes, sometimes called “revenue recycling” (e.g., labor

taxes);

•

rebate to sources to help defray compliance costs of covered sources (e.g.,

according to their production levels);

•

fund programs (or provisions) that could reduce transition costs, such as worker

retraining and relocation programs, market facilitation programs, technology

development programs, tax credits, loan guarantees, etc.;

•

provide payments to address distributional concerns (e.g., tax credits to lowincome consumers); or

•

fund programs that may have little to do with reducing GHG emissions but that

garner wider support for the legislation.

As discussed in a later section, how any revenues are used may help to minimize the overall costs

of the GHG reductions, or, conversely, may lead to higher costs.

Market Facilitation Tools

Even when market mechanisms are used to help control emissions, markets do not work

perfectly; complementary, typically non-regulatory, policies may help to achieve reductions at the

lowest possible costs. Public or targeted information programs can help prepare people for the

changes a GHG control policy may demand, and gain their support for it.

Additionally, technical assistance programs—like several existing federal voluntary programs,

such as the Climate Leaders or Energy Star programs48—can help consumers and businesses to

make efficient choices. Technical assistance programs may provide, for example, calculation

tools, training, and access to information. Programs may work with equipment suppliers to

commercialize products that are more efficient or emit fewer GHGs, as has occurred with, for

example, Energy Star home electronics initiatives, or the Mobile Air Conditioning Climate

Protection Partnership. Most experts agree that such programs work best when targeted to address

specific decision-makers or imperfections in the market, and that the GHG reductions they could

yield by themselves are limited.

48

A number of federal voluntary programs help businesses, other institutions and consumer to identify how they

contribute to GHG emissions and to identify and carry out changes that can lead to GHG reductions and frequently

save money. For more information, see http://yosemite.epa.gov/gw/StatePolicyActions.nsf/webpages/

VoluntaryPartnershipPrograms.html.

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Perceived risks can sometimes make consumers and investors reticent to make changes or invest

in new technologies. Risk-sharing policy tools can include loan guarantees, insurance, or tax

incentives. Public information and education campaigns are additional tools that can support a

policy’s acceptability and effectiveness.

Tools to Stimulate Technological Change

Achieving deep GHG reductions from projected levels—necessary to avoid most projected

climate change—would require extraordinary changes in how energy is used and supplied over

time. The cost of reducing GHG emissions would depend critically on development and

deployment of improved technologies that can reduce emissions at lower costs than current

technologies. While public policies clearly have led to major technological advances in other

fields (e.g., developing nuclear energy, putting a man on the moon), the link between policy tools

and the technological advance that could be expected is unpredictable.

Policy tools can act on the demand for new technologies, or on the supply. Two types of policy

tools act primarily to stimulate demand for new technologies:

•

“Technology-forcing” regulations49 have effectively stimulated demand for better

(and more cost-effective) technologies in the past. “... [T]echnology-forcing

policies respond to the reality that the world is not static and that policy itself can

create and shape the options society faces in meeting its needs.”50 However,

economists prefer price incentives to stimulate technological change, because it

decentralizes decision-making to consumers and suppliers, and is arguably more

cost-effective.

•

Tax incentives can reduce the price to purchasers of certain technologies. The

Energy Policy Act of 2005 (P.L. 109-58 ), for example, extended numerous tax

credits to individuals and businesses to make investments in energy efficiency or

renewable energy generation that meet certain criteria, in order to accelerate

technology deployment.

Other policy tools primarily act on the supply of technologies—increasing incentives for

technology suppliers to conduct research and development (R&D) and to commercialize more

advanced technologies:

•

Subsidies to research and develop new or improved technologies are a common

tool of federal policy, including current approaches to mitigating climate change.

Federal appropriations of billions of dollars have been enacted in recent years to

stimulate more efficient energy technologies; renewable, nuclear, and “clean

coal” technologies; and approaches like alternatives to gasoline or diesel fuel for

vehicles. These subsidies can take the form of tax credits for R&D, cost-sharing

grants or contracts, direct investments, loan guarantees and others.

49

“Where a regulator mandates a standard that cannot be met with existing technology,” according to Gerard, David,

and Lester Lave. “Experiments in Technology Forcing: Comparing the Regulatory Processes of US Automobile Safety

and Emissions Regulations.” International Journal of Technology, Policy and Management 7 (2007): 1-14.

50

Leone, Robert. “Technology-Forcing Public Policies and the Automobile.” In Essays in Transportation Economics

and Policy. Edited by J. Gomez-Ibanez, W. Tye, and C. Winston. Washington, DC: Brookings Institution 1999, pp.

291-323.

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Climate Change: Current Issues and Policy Tools

•

Technology awards or prizes are sometimes offered to innovators that develop

advanced technologies that meet specified criteria.

•

Government procurement policies can drive technological development forward,

by setting challenging standards for performance and guaranteeing purchase of

that technology at a particular (attractive) price, or by purchasing a less-emitting

technology even if it is not the lowest cost alternative. Both types of procurement

policies have been used by the federal government to advance technologies that

emit fewer GHGs than more conventional technologies.

•

“Manhattan Project”-like federal research has been proposed by some experts,

who argue that a focused cadre of researchers, with sufficient resources and

allowed to pursue high-risk, high-payoff projects could facilitate technological

“breakthroughs” that could facilitate radical change in energy systems.

Some policy tools that may affect the advance of technologies could be indirect. For example,

incentives to ensure a sufficient supply from universities of well trained scientists and engineers

in GHG mitigation-related fields could be a component of promoting technological advance.

Unintended Consequences for Technology Incentives

Some policy choices to address one problem may have ancillary effects on technology incentives.

For example, if a GHG cap-and-trade program were to set a “safety valve” to limit maximum

costs—by setting a ceiling on the maximum price of GHG allowances—it would tend to

discourage investors who might take technology development risks in order to capture the profits

of high prices or of temporary price-spikes that often occur in markets. Price floors, on the other

hand, may help reduce the risks to technology investors by making certain the minimum value the

investment may have.

Options to Ease the Economic Transition

A major component of costs to mitigate GHG emissions results because the U.S. economy has

optimized its infrastructure to depend on fossil fuels, particularly coal, and on private, petroleumdependent vehicles for transportation. This has been efficient (disregarding existing subsidies),

without factoring in the environmental, energy security and other “external” costs. Several policy

mechanisms can help to ease the transition of the current economy to one optimized around lowGHG emissions:

•

timing the total required GHG reductions to coincide with normal retirements of

equipment and infrastructure and when new investments may be made;51

•

trading, banking and borrowing of allowances allow sources to manage the

timing of their reductions at least cost;

51

However, some experts suggest that much capital can be maintained to last for decades longer than its nominal

“lifetime” and that the benefits of timing regulations to coincide with capital turnover may frequently be over-stated.

See, for example, Lempert, Robert J., Stephen W. Popper, Susan A. Resetar, and Stuart L. Hart. Capital Cycles and the

Timing of Climate Change. Arlington, VA: Prepared for the Pew Center on Global Climate Change, October 2002.

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Climate Change: Current Issues and Policy Tools

•

market facilitation tools, described above, can help sources make optimal

decisions, including information campaigns that help sources anticipate the

regulatory regime;

•

investment in appropriate infrastructure (important also for state, local and

private entities) that enables deployment of emerging technologies; and

•

regulatory and permitting regimes that are adequately prepared for new

technologies in new locations (e.g., in permitting carbon capture and storage

technologies, or resolving “solar rights” issues).

In addition, the private sector is concerned about the possible international competitiveness and

trade impacts of GHG reductions in the United States. Some policy tools that could be applied,

although some could encounter potential challenges under the World Trade Organization (WTO)

rules, include

•

border tax adjustments that would raise the prices of imports from countries

without GHG controls comparable to those of the United States;

•

“international reserve” allowances that importers of certain goods must purchase

(raising the cost of imports) if the country of origin does not apply GHG controls

comparable to those of the United States;

•

giving, over some period, allowances or revenues from sales of allowances to

affected industries in order to facilitate adjustment;

•

in the process of crafting domestic policies, negotiating with potentially affected

WTO Members to seeks ways to avoid imposing restrictive import measures;

•

working within the WTO to change or clarify rules to permit the imposition of

import restrictions by countries adopting trade-vulnerable GHG control

requirements; and

•

working multilaterally to have GHG emission controls applied equitably to

sources internationally (see discussion below) and to avoid WTO challenges.

The design of competitiveness-oriented policy tools would require caution to avoid challenge

under WTO as unfair trade practices.

International Policy Tools

The effectiveness of U.S. policies to address climate change will depend on the collaboration of

almost all other countries, especially the largest emitters. Some of the large emitters, such as

Japan and nations of the European Union, already have committed to reducing their GHG

emissions below year 1990 levels and have proposed further reductions beyond the current Kyoto

Protocol (discussed in a later section). However, the United States, China and other large

developing country emitters have not committed to quantified GHG reductions, and the position

of Russia beyond 2012 remains a question. The United States can use a number of policy tools in

order to encourage effective, global GHG reductions:

•

leadership and relationship-building;

•

strategic policy leverage (including quid pro quo);

•

capacity building and other technical assistance;

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•

financial assistance;

•

agreement on standards for international investment; and

•

contributions of research and technological developments.

There are additional options, and a multitude of variants in designing each of these policy tools.

Tools to Stimulate Adaptation to Climate Change

While most of this section, and this report, emphasizes options to mitigate GHG emissions and

projected climate change, a growing set of legislative proposals aims to promote understanding of

climate change impacts, and to stimulate effective adaptation to climate change. Included in the

policy toolbox to promote efficient adaptation to climate change are, to name a few:

•

research to improve characterization of future climate change, 52 its variability,

and its potential implications for different sectors and ecosystems;

•

public information, both broad and targeted to specific risks, including access to

robust characterization of future climate conditions and associated risks;

•

programs to develop practical tools to assist decision-makers to understand the

implications of climate change for their areas of operation (e.g., water

management, infrastructure engineering, disease vector prediction, etc.);

•

financial or regulatory incentives to reduce risks (e.g., to discourage construction

in vulnerable flood plains; to encourage insurers to include climate change risks

in their premium schedules; etc.);

•

improved emergency planning to reduce risks and respond to extreme weather

events (e.g., droughts, tornadoes, etc.); and

•

acquisition of key assets, such as easements in coastal zones or lands along

wildlife migratory routes, that may be valuable for long-term adaptation.

Policy tools to encourage private and public sector adaptations, like the research to support them,

are relatively undeveloped compared to work on GHG mitigation.

Choices Ahead for Policy Makers

With the current flurry of activity to address GHG emissions at local, state, and international

levels, as well as the introduction of numerous GHG reduction bills in the 110th Congress, it

seems likely that Members of Congress will have to decide whether the time is appropriate to

legislate a climate strategy, and what forms legislation should take. In considering the

alternatives, policy makers may wish to answer for themselves such questions as

52

Current scientific uncertainty is very wide not just on human-induced climate change, but also on underlying natural

variability. What humans and ecosystems will experience, and may need to adapt to, will be the combination of both

influences on climate.

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•

whether the risks of human-induced climate change are sufficiently certain to call

for policy actions to mitigate the causes and/or adapt to perceived inevitable

change;

•

how a domestic policy package can be designed that balances the risks of climate

change with costs that are accepted as reasonable and fairly distributed;

•

how domestic policy would interact with international negotiations to avoid

unacceptable climate risks while distributing the effort equitably among countries

and sectors; and

•

when and how to promote appropriate adaptation by private and public decisionmakers to the uncertain climate ahead.

Further Information

Reports for Members of Congress, providing more detailed information on topics introduced in

this report, can be found on the CRS website, on the Climate Change Issues in Focus pages, or by

calling 707-5700.

Author Contact Information

(name redacted)

Specialist in Energy and Environmental Policy

[redacted]@crs.loc.g

ov, 7-....

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