Climate Change: Trends in Greenhouse Gas Emissions and Emissions
Intensity in the United States and Other High-Emitting Nations
(28-OCT-03, GAO-04-146R).
In February 2002, the President reaffirmed a previous U.S.
commitment to stabilize atmospheric concentrations of carbon
dioxide and other greenhouse gases at a level designed to prevent
dangerous human interference with the earth's climate. At the
same time, he announced a Global Climate Change Initiative to
reduce the rate of increase of greenhouse gas emissions in the
United States between 2002 and 2012. Specifically, he established
the goal of reducing the "emissions intensity" of the U.S.
economy by 18 percent, a reduction 4 percentage points greater
than would be expected absent any new policy. Congress asked us
to describe how U.S. emissions and emissions intensity compare to
the world's other highest emitters. Specifically, this report
focuses on (1) how greenhouse gas emissions and the emissions
intensity of the United States and the nine nations with the
next-highest emissions changed from 1980 to 2000, (2) how such
emissions and the emissions intensities of the same nations are
expected to change between 2001 and 2025, and (3) how meeting the
administration's goal of reducing emissions intensity by 18
percent would affect cumulative U.S. emissions between 2002 and
2012.
-------------------------Indexing Terms-------------------------
REPORTNUM: GAO-04-146R
ACCNO: A08813
TITLE: Climate Change: Trends in Greenhouse Gas Emissions and
Emissions Intensity in the United States and Other High-Emitting
Nations
DATE: 10/28/2003
SUBJECT: Air pollution control
Comparative analysis
Foreign governments
Projections
Greenhouse gasses
Canada
China
France
Germany
Global Climate Change Initiative
India
Italy
Japan
South Korea
United Kingdom
United States
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GAO-04-146R
United States General Accounting Office Washington, DC 20548
October 28, 2003
The Honorable Ernest F. Hollings
Ranking Member
Committee on Commerce, Science, and Transportation United States Senate
The Honorable John F. Kerry
Ranking Member
Subcommittee on Oceans, Fisheries, and Coast Guard Committee on Commerce,
Science, and Transportation United States Senate
Subject: Climate Change: Trends in Greenhouse Gas Emissions and Emissions
Intensity in the United States and Other High-Emitting Nations
In February 2002, the President reaffirmed a previous U.S. commitment to
stabilize atmospheric concentrations of carbon dioxide and other
greenhouse gases at a level designed to prevent dangerous human
interference with the earth's climate. At the same time, he announced a
Global Climate Change Initiative to reduce the rate of increase of
greenhouse gas emissions in the United States between 2002 and 2012.
Specifically, he established the goal of reducing the "emissions
intensity" of the U.S. economy by 18 percent, a reduction 4 percentage
points greater than would be expected absent any new policy.
Emissions intensity is a ratio calculated by dividing emissions in a given
year by economic output for that year. For example, in 2000, U.S.
greenhouse gas emissions were 1,909 million metric tons of carbon
equivalent,1 and U.S. economic output was $9,216 billion;2 dividing these
numbers yields an emissions intensity of 207 tons of emissions per million
dollars of economic output. Changes in emissions intensity depend on the
relative rate of change in emissions and economic output. For example, if
emissions and economic output increase (or decrease) at the same rate,
intensity remains constant. However, if emissions increase faster than
economic
1To allow for comparisons among greenhouse gases, which differ in terms of
their effects on the atmosphere and their expected lifetimes, emissions
are typically measured in million metric tons of carbon equivalent, which
we refer to as million metric tons.
2Economic output (gross domestic product, or GDP) is expressed in billions
of 1996 dollars, as reported in the Economic Report of the President,
2002.
GAO-04-146R Greenhouse Gas Emissions Intensity
output, intensity increases. Conversely, if economic output rises faster
than emissions, intensity decreases.
You asked us to describe how U.S. emissions and emissions intensity
compare to the world's other highest emitters. Specifically, as agreed
with your offices, this report focuses on (1) how greenhouse gas emissions
and the emissions intensity of the United States and the nine nations with
the next-highest emissions changed from 1980 to 2000, (2) how such
emissions and the emissions intensities of the same nations are expected
to change between 2001 and 2025, and (3) how meeting the administration's
goal of reducing emissions intensity by 18 percent would affect cumulative
U.S. emissions between 2002 and 2012.
To accomplish these objectives, we analyzed data from the Energy
Information Administration (EIA), an independent statistical and
analytical agency within the U.S. Department of Energy. After the United
States, the next nine nations (excluding Russia3) with the highest 2001
emissions, in declining order, are China, Japan, India, Germany, Canada,
the United Kingdom, Italy, South Korea, and France. With the United
States, these nations accounted for 59 percent of the world's
energy-related carbon emissions in 2001 and are projected to account for
the same percentage in 2025. For the first two objectives, we used data on
emissions of energy-related carbon dioxide (generally, emissions from the
consumption of fossil fuels) because we did not find data on the other
greenhouse gas emissions for these high-emitting nations. (Energy-related
carbon dioxide accounts for an estimated 85 percent of world greenhouse
gas emissions, according to the International Energy Agency.4) For the
third objective, we used data on U.S. emissions of all greenhouse gases.
We also analyzed the administration's February 2002 Global Climate Change
Initiative and supporting documentation.
Results in Brief
Between 1980 and 2000, energy-related carbon dioxide emissions increased
in the United States and six of the other nine highest-emitting nations.
Emissions increased 22.5 percent in the United States, while the largest
increase occurred in South Korea (231.4 percent). Emissions decreased in
the United Kingdom (10.1 percent), France (19.9 percent), and Germany
(22.3 percent). During the same period, emissions intensities fell in the
United States (34.7 percent) and the other nations reviewed except India.
The decrease was the smallest in Italy (19.6 percent) and the greatest in
China (68.9 percent). In India, emissions intensity increased slightly but
was essentially stable.
Between 2001 and 2025, energy-related carbon dioxide emissions are
expected to increase in all 10 nations. U.S. emissions are projected to
rise 43.5 percent, not
3Although Russia was the world's third-largest emitter of energy-related
carbon dioxide emissions in 2001, we did not include Russia in our study
because EIA did not project emissions intensity for Russia for 2025.
4The International Energy Agency is the energy forum for the 26 member
nations of the Organization for Economic Cooperation and Development.
Page 2 GAO-04-416R Greenhouse Gas Emissions Intensity
counting any reductions from the administration's initiative. The smallest
increase is expected in Germany (15.2 percent), and the largest increase
is expected in China (121.6 percent). During the same period, emissions
intensities are expected to decrease in all 10 nations. In the United
States, the expected decrease is 30.1 percent. Decreases in intensities
are expected to be smallest in Japan (20.8 percent) and largest in China
(47.6 percent).
If the administration's goal of reducing U.S. emissions intensity by 18
percent between 2002 and 2012 is met, cumulative emissions for that
11-year period would be about 500 million metric tons of carbon equivalent
lower than the 23,162 million metric tons that would otherwise be
expected, according to an EIA projection. Specifically, achieving the
administration's goal would limit emissions to no more than 22,662 million
metric tons-2 percent below the level that would otherwise be expected
over the period.
In commenting on a draft of this report, a senior EIA official concurred
without further comment, and a senior staff economist at the Council of
Economic Advisers, part of the Executive Office of the President, provided
technical comments, which we incorporated where appropriate.
Background
Carbon dioxide and certain other gases trap some of the sun's heat in the
earth's atmosphere and prevent it from returning to space. The trapped
heat warms the earth's climate, much like the process that occurs in a
greenhouse. Hence, the gases that cause this effect are often referred to
as greenhouse gases. The most prevalent of these gases is carbon dioxide,
which results from the combustion of coal and other fossil fuels in power
plants, the burning of gasoline in vehicles, and other sources. In recent
decades, concentrations of these gases have built up in the atmosphere,
giving rise to concerns that continuing increases might interfere with the
planet's climate, for example, by increasing temperatures or changing
precipitation patterns.
In 1992, the United States ratified the United Nations Framework
Convention on Climate Change, which was intended to stabilize the buildup
of greenhouse gases in the earth's atmosphere, but did not impose specific
goals or timetables for limiting emissions. In 1997 the United States
participated in drafting the Kyoto Protocol, an international agreement to
specifically limit greenhouse gas emissions, and in 1998 it signed the
protocol. However, the previous administration did not submit the protocol
to the Senate for advice and consent, which are necessary for
ratification. In March 2001, the President announced that he opposed the
protocol.
Nearly a year later, in February 2002, the President announced his Global
Climate Change Initiative, which focuses on reducing emissions intensity
compared to what would otherwise be expected, but not necessarily on
reducing the level of emissions. EIA projects that, in the absence of new
policies, U.S. greenhouse gas emissions intensity will decrease from 183
metric tons of emissions per million dollars of GDP in 2002 to 158 metric
tons in 2012, a decrease of 14 percent. The administration's goal is to
reduce emissions intensity to 151 metric tons per million dollars of GDP-a
Page 3 GAO-04-416R Greenhouse Gas Emissions Intensity
further reduction of 4 percentage points, bringing the total reduction to
18 percent by 2012.
According to EIA, reductions in emissions intensity can have various
causes. For example, in the last half-century the U.S. energy supply has
come to rely less on fuels with a high carbon content as nuclear energy,
hydropower, and natural gas have been increasingly substituted for coal
and oil in power generation. The use of renewable energy sources, such as
ethanol, has also increased in the United States. In nations such as China
and India, lower emissions intensities result primarily from rapid
economic growth, rather than from a switch to less carbon-intensive fuels.
Emissions Increased, While Intensities Decreased, in Most of the 10
Nations between 1980 and 2000
Energy-related carbon emissions increased in the United States and six of
the other nine highest emitters between 1980 and 2000. In the United
States, emissions increased 22.5 percent. The increases were relatively
small in Italy (17.5 percent) and Japan (18.8 percent) and relatively
large in India (203.7 percent) and South Korea (231.4 percent). Emissions
decreased in the United Kingdom (10.1 percent), France (19.9 percent), and
Germany (22.3 percent). (See table 1.)
Table 1: Emissions in 10 Nations, 1980 and 2000 (ranked by 2000 emissions
levels)
Emissions (million metric
tons) Percent change
Average annual
Nation 1980 2000 Cumulative rate
United States 1,288 1,578 22.5 1.0
China 394 780 98 3.4
Japan 261 310 18.8 0.9
India 82 249 203.7 5.6
Germany 291 226 -22.3 -1.3
Canada 125 158 26.4 1.2
United Kingdom 168 151 -10.1 -0.5
Italy 103 121 17.5 0.8
South Korea 35 116 231.4 6.0
France 136 109 -19.9 -1.1
Sources: EIA (data); GAO (calculations).
Emissions intensity decreased 34.7 percent in the United States and also
decreased in eight of the other nine nations between 1980 and 2000. The
decreases were the smallest in Italy (19.6 percent) and South Korea (20.8
percent) and the largest in France (47.2 percent) and China (68.9
percent). In contrast, intensity increased 1.3 percent in India. (See
table 2.)
Page 4 GAO-04-416R Greenhouse Gas Emissions Intensity
Table 2: Emissions Intensities in 10 Nations, 1980 and 2000 (ranked by
2000 emissions levels)
Emissions intensity (metric tons
of carbon equivalent per million
dollars of economic output) Percent change
Average annual
Nation 1980 2000 Cumulative rate
United States 269 176 -34.7 -2.1
China 2,407 749 -68.9 -5.8
Japan 79 55 -30.5 -1.8
India 514 520 1.3 0.1
Germanya 108 84 -22.0 -2.8
Canada 308 226 -26.7 -1.5
United Kingdom 210 116 -44.9 -3.0
Italy 125 100 -19.6 -1.1
South Korea 236 187 -20.8 -1.2
France 116 61 -47.2 -3.2
Sources: EIA (data); GAO (calculations).
aIntensity data are for 1991 (the first year for which an intensity figure
is available for all the territory comprising unified Germany) and 2000;
the percentage changes are calculated accordingly.
Emissions Are Projected to Increase and Intensities to Decrease in All 10
Nations between 2001 and 2025
Energy-related carbon dioxide emissions levels of the United States and
the nine other high-emitting nations are projected to increase through
2025, while their emissions intensities are expected to decrease over the
same period, according to EIA.5 U.S. emissions are projected to increase
43.5 percent.6 Smaller increases are expected in Germany (15.2 percent)
and the United Kingdom (19 percent). Larger increases are expected in
India (102.4 percent) and China (121.6 percent). (See table 3.)
5EIA cautions that its projections present plausible paths or trends for
the future based on current laws and regulations; do not anticipate
volatile social, political, or economic events; and are not intended as
precise predictions of future events. In its most recent International
Energy Outlook, EIA reported on the accuracy of its past projections; see
the Scope and Methodology section for additional details.
6This projection for the United States does not include the
administration's initiative.
Page 5 GAO-04-416R Greenhouse Gas Emissions Intensity
Table 3: Projected Emissions in 10 Nations, 2001 and 2025 (ranked by 2025
level of emissions)
Emissions (million metric
tons) Percent change
Average annual
Nation 2001 2025 Cumulative rate
United States 1,559 2,237 43.5 1.5
China 832 1,844 121.6 3.3
India 250 506 102.4 2.9
Japan 316 382 20.9 0.8
Germany 223 257 15.2 0.6
Canada 155 206 32.9 1.2
South Korea 121 206 70.2 2.2
United Kingdom 153 182 19 0.7
Italy 121 146 20.7 0.8
France 108 135 25 0.9
Sources: EIA (data); GAO (calculations).
During the same time period, emissions intensities are projected to
decrease in all 10 nations. The decrease in the United States is projected
to be 30.1 percent. The smallest decreases are expected in Japan (20.8
percent) and France (29.4 percent), and the largest decreases are expected
in India (40.6 percent) and China (47.6 percent). (See table 4.)
Table 4: Projected Emissions Intensities in 10 Nations, 2001 and 2025
(ranked by 2025 level of emissions)
Emissions intensities (metric tons
of carbon equivalent per million
dollars of economic output Percent change
Average annual
Nation 2001 2025 Cumulative rate
United States 166 116 -30.1 -1.5
China 693 363 -47.6 -2.7
India 480 285 -40.6 -2.1
Japan 72 57 -20.8 -1.0
Germany 98 67 -31.6 -1.5
Canada 209 146 -30.1 -1.5
South Korea 217 137 -36.9 -1.9
United 104 73 -29.8 -1.5
Kingdom
Italy 96 67 -30.2 -1.5
France 68 48 -29.4 -1.4
Sources: EIA (data); GAO (calculations).
Administration's Initiative Would Reduce Cumulative U.S. Emissions 2
Percent below the Otherwise Expected Level
If the administration's goal is met, cumulative emissions for 2002 through
2012 would be about 500 million metric tons lower than otherwise expected.
EIA projected that, in the absence of any policy change, cumulative U.S.
emissions from 2002 through 2012 would be 23,162 million metric tons. The
administration projected that the initiative would reduce that total to no
more than 22,662 million metric tons. The
Page 6 GAO-04-416R Greenhouse Gas Emissions Intensity
reduction in emissions attributed to the initiative is expected to
increase each year through 2012, reaching 106 million metric tons in that
year, which would represent a 5 percent decrease from the level otherwise
expected. Cumulatively, for 2002 through 2012, the initiative is projected
to reduce emissions by 500 million metric tons, or 2 percent below the
otherwise expected level.
Observations
Emissions increased in 7 out of the 10 highest-emitting nations from 1980
through 2000 and are projected to increase in all 10 through 2025.
Emissions intensity decreased in all but one of the nations from 1980
through 2000 and is projected to decrease in all 10 highest-emitting
nations through 2025.
Agency Comments
We provided a draft of this report for review and comment to the Secretary
of Energy and to the Chairman of the Council of Economic Advisers, a part
of the Executive Office of the President. The Director of EIA's Office of
Integrated Analysis and Forecasting concurred with the report without
further comment. A Senior Staff Economist at the Council of Economic
Advisers provided technical comments, which we incorporated where
appropriate.
Scope and Methodology
To answer our objectives, we analyzed EIA data and the administration's
February 2002 Global Climate Change Initiative and supporting
documentation. For our analysis of emissions from 1980 through 2000 and
from 2001 through 2025, we used data on energy-related carbon dioxide
emissions (generally, emissions from the consumption of fossil fuels).7
For our analysis of emissions intensity from 1980 through 2000, we used
intensity data calculated using 1995 U.S. dollars and carbon dioxide
emissions from the consumption and flaring of fossil fuels. For the
analysis of emissions intensity from 2001 through 2025, we used intensity
data calculated using 1997 U.S. dollars and carbon dioxide emissions. For
the discussion of the initiative, we used Environmental Protection Agency
data for all greenhouse gas emissions.
We did not independently assess the reliability of EIA data nor the
validity of EIA models used in this report. In its most recent
International Energy Outlook, EIA reported on the accuracy of certain of
its projections of energy consumption and other measures. For example, it
noted that its 1997 projections of 2000 energy consumption were accurate
for North America (which includes Canada and the United States), 4 percent
too high for Western Europe (which includes France, Germany, Italy, and
the United Kingdom), and 11 percent too high for developing nations in
Asia (which includes China and India), a region affected by a severe
recession in the late 1990s.8 We performed our work between April and
October 2003
7These emissions data do not include carbon dioxide emitted from natural
gas flaring.
8See EIA's International Energy Outlook 2003, DOE/EIA-0484 (2003).
Page 7 GAO-04-416R Greenhouse Gas Emissions Intensity
in accordance with generally accepted government auditing standards,
except as noted.
As arranged with your offices, unless you publicly announce the contents
of this report earlier, we plan no further distribution until 10 days from
the report date. At that time, we will send copies to the appropriate
congressional committees; the Secretary of Energy; and the Chairman,
Council of Economic Advisers. In addition, the report will be available at
no charge on the GAO Web site at http//:www.gao.gov.
Should you or your staff need further information, please contact me or
David Marwick at (202) 512-3841. Anne K. Johnson and Kevin Tarmann made
key contributions to this report. John Delicath and Cynthia Norris also
made important contributions.
John B. Stephenson Director, Natural Resources
and Environment
(360316)
Page 8 GAO-04-416R Greenhouse Gas Emissions Intensity
*** End of document. ***