a

GAO

United States General Accounting Office

Report to Congressional Requesters

December 2003 CLIMATE CHANGE

Selected Nations’ 

Reports on 

Greenhouse Gas 

Emissions Varied in 

Their Adherence to 

Standards

GAO-04-98
In their most recent reviews, expert teams found that the United Kingdom’s 

2000 and 2002 reports on greenhouse gas emissions and the United States’s 

2000 report were largely complete, although the teams noted minor findings, 

such as the lack of information on quality assurance methods, which the 

nations were encouraged, but not required, to include in their submissions. 

In contrast, they found that Germany’s 2001 and Japan’s 2000 reports lacked 

critical elements, such as the required documentation that was essential to 

understanding them. Preliminary checks found that all four nations’ 2003 

reports were largely complete. 

Secretariat staff have not assessed inventories from China and India because 

these nations have not submitted them. According to Secretariat records, 

China and India plan to submit inventories in February 2004 and November 

2003, respectively. Secretariat staff assessed Mexico’s most recent 

inventory, but they reported few details about it because their policy is to 

consolidate the findings of all the developing nations’ inventories submitted 

during a year.

To improve the inventories, the parties are changing the reporting standards 

and review process. For example, starting in 2004, developed nations must 

present their inventory reports in a standardized format to facilitate review, 

and developing nations must report data for more years and gases than 

before. Also, in 2003, the parties began conducting more rigorous reviews of 

developed nations’ inventories, but no such changes for developing nations 

are planned. 

Carbon Dioxide Emissions for the Seven Nations in GAO’s Study, Actual and Projected 

In 1992, the United States and other 

parties, including both developed 

and developing nations, agreed to 

try to limit dangerous human 

interference with the climate by 

participating in the United Nations 

Framework Convention on Climate 

Change. The parties agreed, among 

other things, to report on their 

emissions of carbon dioxide and 

five other gases whose buildup in 

the atmosphere is believed to affect 

the climate. The parties developed 

standards for these reports and 

processes for periodically 

evaluating the reports. Expert 

teams selected by the parties 

review the developed nations’ 

reports; staff of the Framework 

Convention’s administrative arm 

(the Secretariat) assess developing 

nations’ reports. GAO agreed to 

describe the results of the most 

recent reviews and assessments of 

reports from selected economically 

developed and developing nations, 

as well as the parties’ plans to 

improve the reports. 

For the developed nations, GAO 

agreed to study four geographically 

dispersed nations with high levels 

of emissions—Germany, Japan, the 

United Kingdom, and the United 

States. For the developing nations, 

GAO studied China, India, and 

Mexico, which also have high 

emissions levels and are 

geographically dispersed. These 

nations are not representative of 

others; therefore, GAO’s findings 

cannot be generalized. 

www.gao.gov/cgi-bin/getrpt?GAO-04-98.

To view the full report, including the scope 

and methodology, click on the link above. 

For more information, contact John 

Stephenson, 202-512-3841 or 

stephensonj@gao.gov. 

Highlights of GAO-04-98, a report to the 

Chairmen, Committee on Energy and 

Commerce and its Subcommittees on 

Energy and Air Quality and Oversight and 

Investigations, House of Representatives 

December 2003

CLIMATE CHANGE 

Selected Nations' Reports on Greenhouse 

Gas Emissions Varied in Their Adherence 

to Standards 
Page i GAO-04-98 Greenhouse Gas Emissions Reports

Contents

Letter 1

Results in Brief 4

Background 6

Recent Reviews Found That U.K. and U.S. Inventories Were Largely 

Complete, but German and Japanese Inventories Lacked Critical 

Elements 14

Little Nation-Specific Inventory Information Is Available for the 

Three Developing Nations 15

The Four Developed Nations Reported Generally High Confidence 

in Their Latest Emissions Data, but Future Assessments of 

Confidence Must Be More Precise 17

The Parties Are Taking Steps to Improve the Quality of Emissions 

Data 21

Scope and Methodology 23

Agency Comments 24

Appendixes

Appendix I: Results of Expert Reviews of the Four Developed Nations’ 

Inventories 26

Appendix II: GAO Contacts and Staff Acknowledgments 29

GAO Contacts 29

Staff Acknowledgments 29

Tables Table 1: Comparative Statistics of the Seven Nations in Our Study 9

Table 2: Four Developed Nations’ Ratings of Confidence in Their 

Data for Total Emissions in 2001 19

Table 3: Results of the Most Recent Expert Reviews of the Four 

Developed Nations’ Inventories 27

Figures Figure 1: Carbon Dioxide Emissions by Developed and Developing 

Nations and Nations with Economies in Transition, 1970 

through 2025, Actual and Projected 7

Figure 2: Carbon Dioxide Emissions for the Seven Nations in Our 

Study, Actual and Projected 8
Contents

Page ii GAO-04-98 Greenhouse Gas Emissions Reports

Abbreviations

EIA Energy Information Administration

EPA Environmental Protection Agency

IPCC Intergovernmental Panel on Climate Change

This is a work of the U.S. government and is not subject to copyright protection in the 

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Page 1 GAO-04-98 Greenhouse Gas Emissions Reports

United States General Accounting Office

Washington, D.C. 20548

A

December 23, 2003 Letr

The Honorable W.J. “Billy” Tauzin

Chairman, Committee on Energy and Commerce

House of Representatives

The Honorable Joe Barton

Chairman, Subcommittee on Energy and Air Quality

Committee on Energy and Commerce

House of Representatives

The Honorable James Greenwood

Chairman, Subcommittee on Oversight and Investigations

Committee on Energy and Commerce

House of Representatives

The Congress recently debated the need to limit U.S. emissions of the socalled “greenhouse gases”—whose buildup in the atmosphere is widely 

believed to adversely affect the climate. This debate dates back to at least 

1992, when the United States and most of the other nations of the world 

took steps toward ensuring that worldwide progress in reducing 

greenhouse gas emissions could eventually be measured. At that time, the 

nations negotiated the United Nations Framework Convention on Climate 

Change (hereafter called the Framework Convention) with the aim of 

stabilizing atmospheric concentrations of carbon dioxide and five other 

greenhouse gases.1

 The nations also agreed to periodically report on their 

greenhouse gas emissions.2

1

The five other gases are methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, 

and sulfur dioxide.

2

In 1997, the United States and other parties to the Framework Convention participated in 

drafting the Kyoto Protocol, an international agreement to specifically limit emissions of the 

six greenhouse gases, and in 1998 the United States signed the protocol. However, President 

Clinton did not submit the protocol to the Senate for advice and consent, which are 

necessary for ratification. In March 2001, President Bush announced that he opposed the 

protocol. 
Page 2 GAO-04-98 Greenhouse Gas Emissions Reports

As of November 2003, 188 parties had ratified the Framework Convention, 

including the United States.3

 Of this total, 40 parties—39 nations and the 

European Union as a whole—are listed in Annex I of the convention. The 

39 Annex I nations include the economically developed nations of the 

world as well as nations whose economies are in transition, including the 

Russian Federation, the Baltic states, and several central and eastern 

European nations. The Annex I nations have agreed to report annually on 

their emissions levels. The annual reports, called inventories, generally 

reflect estimated—rather than directly measured—data. The remaining 148 

nations that are party to the Framework Convention but are not included in 

Annex I—“non-Annex I nations”—are generally classified as economically 

developing nations. These nations also agreed to report on their emissions, 

but in less detail and less frequently than the Annex I nations. 

Recognizing that good-quality data on all nations’ greenhouse gas 

emissions are critical to determining whether the Framework Convention 

is successful at stabilizing greenhouse gas emissions worldwide, the parties 

to the convention are working in several ways to ensure the quality of the 

emissions data that nations report. First, with technical assistance from the 

Intergovernmental Panel on Climate Change (IPCC),4

 the parties developed 

extensive procedures for all nations to follow when estimating and 

reporting their greenhouse gas emissions and removals (removals offset 

emissions—for example, forests absorb carbon dioxide, removing it from 

the air). In addition, the developed Annex I nations agreed to provide funds 

to help the non-Annex I nations develop their inventories. Finally, the 

parties agreed that nations’ estimates of their emissions, and the 

documentation that supports these estimates, would undergo one of two 

main types of review: one for Annex I nations and another for non-Annex I 

nations. Annex I nations’ inventories periodically undergo individual 

reviews performed by teams of experts assembled from the party nations. 

The expert reviews are extensive, examining all aspects of each inventory 

and its preparation to determine whether the inventory complied with the 

estimating and reporting procedures. The Framework Convention’s 

3

We use the term “ratified” to indicate that nations have ratified, accepted, approved, or 

acceded to the Framework Convention. The convention entered into force after it was 

ratified by 50 nations.

4

Established by the World Meteorological Organization and the United Nations Environment 

Program in 1988, the IPCC supports the parties by providing scientific, technical, and 

socioeconomic advice through periodic assessments and special publications, such as the 

guidelines it developed on estimating emissions and removals.
Page 3 GAO-04-98 Greenhouse Gas Emissions Reports

administrative arm, the Secretariat, publishes a report on the findings of 

each nation’s individual expert review. Non-Annex I nations’ inventories are 

assessed by Secretariat staff, who examine all such inventories submitted 

during the year. The assessment is less extensive and evaluative than the 

review of Annex I nations’ submissions. It focuses on identifying problems 

that the developing nations have had with preparing and reporting their 

inventories and ways to improve them. The Secretariat issues one report 

each year discussing its findings on the non-Annex I nations’ inventories in 

summary format, with few nation-specific details. 

We agreed with your offices to (1) describe the results of the most recent 

expert reviews of the greenhouse gas inventories submitted by four 

economically developed nations—Germany, Japan, the United Kingdom, 

and the United States; (2) describe the results of any assessments of the 

inventories of three developing nations—China, India, and Mexico; (3) 

determine the extent to which the developed nations have confidence in 

the quality of their inventory data, and describe any changes that the 

parties to the Framework Convention have made to requirements for 

assessing data confidence in the future; and (4) describe any steps that the 

parties to the Framework Convention are taking as a group to improve the 

quality of future inventories, including when such improvements might be 

in place.

Also as agreed with your offices, in examining these issues, we did not 

independently review the nations’ inventories to assess their quality. 

Instead, we examined the guidance developed for the nations and the 

requirements they are to meet in preparing and reporting their greenhouse 

gas inventories and believe the guidance provides reasonable parameters 

for ensuring good-quality inventory data. We also examined the 

methodology for the reviews of developed nations’ inventories and believe 

it provides reasonable help to reviewers in evaluating the quality of 

inventories. We relied on the findings of the reviews as reported by the 

Secretariat. Regarding the Annex I nations, we agreed to study the two 

European Union nations and the two non-European Union nations with the 

highest levels of emissions that are developed nations, according to the 

most recent data available to the United Nations (2001). Although some 

nations that are considered Annex I nations have economies in transition 

and emit significant levels of greenhouse gases, as agreed, we did not 

include them in our study. Regarding the non-Annex I nations—developing 

nations—we agreed to study China, India, and Mexico because of their high 

levels of greenhouse gas emissions and geographic dispersion. These seven 

nations are not necessarily representative of other parties to the 
Page 4 GAO-04-98 Greenhouse Gas Emissions Reports

Framework Convention; accordingly, our findings are not generalizable to 

the other parties. Although we spoke with U.S. officials who are 

responsible for assembling and managing the U.S. inventory, we did not 

speak with comparable officials in the other six nations. It is our policy to 

contact foreign government officials through the U.S. Department of State, 

and we asked the department to facilitate that contact; however, the 

department did not arrange for those contacts during our review. State 

Department officials asserted that issues of reporting and review under the 

Framework Convention have been particularly sensitive for the developing 

nations; also, foreign governments might not readily grasp the different 

roles of the General Accounting Office and the State Department. As a 

result, according to State Department officials, some governments might 

view a request of this nature from the United States as intrusive, raising 

suspicions about the underlying purpose of such a study. 

Results in Brief The most recent expert reviews of the greenhouse gas inventories 

submitted by Germany, Japan, the United Kingdom, and the United States 

found that the U.K. and U.S. submissions were largely complete, while 

Germany’s and Japan’s submissions lacked certain critical elements. At the 

time of our study, the most recent expert reviews were for inventories 

submitted by Japan, the United Kingdom, and the United States in 2000; by 

Germany in 2001; and by the United Kingdom in 2002. The reviews of the 

U.K. and U.S. inventories found they contained nearly all of the required 

information and noted only relatively minor problems, such as not 

providing information on the quality assurance procedures used. 

Accordingly, the experts’ suggestions for improving those submissions 

were not substantial; for example, the expert review report for the 2000 

U.K. submission suggested that the United Kingdom archive all of the 

documentation supporting its inventory in one location or on the Web. In 

contrast, the reviews of Germany’s and Japan’s inventories found that both 

were missing some important elements. For example, both submissions 

lacked the required report explaining how the emissions estimates were 

developed. The experts suggested fundamental improvements for future 

inventories, such as submitting all of the required information. The 

Secretariat’s preliminary examination of all four nations’ 2003 submissions 

found that they were largely complete and contained national inventory 

reports.

Neither China nor India has submitted an inventory to the Secretariat; 

Mexico submitted an inventory as recently as 2001, which the Secretariat 

assessed. According to the Secretariat, China and India are preparing their 
Page 5 GAO-04-98 Greenhouse Gas Emissions Reports

initial inventories, which, under the Framework Convention, are due within 

3 years of when the convention entered into force for that nation or when 

the financial assistance provided by the developed nations to help with 

reporting becomes available. According to the Secretariat, China’s 

inventory is due by November 2004 and India’s by July 2004. Regarding the 

Secretariat’s assessment of Mexico’s 2001 submission, little information 

that could be directly tied to Mexico was released. Instead, the Secretariat 

consolidated the results with those of the 51 other non-Annex I nations that 

it examined at the same time, as is its usual practice for the assessments. 

The four developed nations reported generally high confidence in the 

emissions data presented in their most recent submissions; however, future 

assessments of confidence in these data must be quantified to produce 

more useful information. For the 2003 and previous submissions, 

developed nations were required to assess as high, medium, or low their 

confidence in their inventory data for each major emission source and 

removal. The developed nations could use either qualitative or quantitative 

methods for making those assessments, and no criteria existed for 

determining which of the three categories was the most appropriate. In 

their 2003 submissions, all four developed nations reported that they had 

high confidence in at least 75 percent of their total emissions data, largely 

because most emissions are carbon dioxide, which is relatively easy to 

estimate with a high degree of accuracy. Effective next year, the developed 

nations are required to assess their confidence in their data using 

quantitative methods and to report numerical ratings instead of reporting 

by the three categories (high, medium, or low). The parties consider using 

quantitative methods to be the better practice because the resulting 

numerical ratings give a more precise assessment of nations’ confidence in 

their data and make it easier for the nations to set priorities when deciding 

how to improve the accuracy of the inventories.

To improve the quality of data on greenhouse gas emissions, the parties to 

the Framework Convention are refining their requirements for nations’ 

inventories and bolstering their review processes, with the changes to take 

effect over the next few years. Changes to the inventory requirements 

affect both Annex I and non-Annex I nations. For example, in addition to 

the new requirement for performing a quantified assessment of data 

confidence, Annex I nations will be required to structure the 

documentation that explains the inventories according to a standardized 

format beginning with their 2004 submissions. For non-Annex I nations, the 

revised requirements are intended to encourage more of the nations to 

submit inventories as well as to improve the quality of the inventories. For 
Page 6 GAO-04-98 Greenhouse Gas Emissions Reports

example, as of 2003, non-Annex I nations that have not yet submitted their 

first inventories must submit data for either 1990 or 1994 in their first 

submissions, and all non-Annex I nations must include data for 2000 when 

they submit their second inventories. This is in contrast to the requirement 

that Annex I nations annually report data for all years, from 1990 to the 

present. In addition, the parties plan to bolster the expert review process 

for Annex I nations. For example, until this year, only a portion of the 39 

Annex I nations underwent an expert review each year; however, beginning 

with the 2003 submissions, each of the 39 nations will be subject to an 

annual expert review. The changes to the review process are intended to 

standardize it and to ensure that reviews are conducted effectively and 

consistently. According to the Secretariat, the parties have no plans to 

change the assessment process for non-Annex I nations’ inventories, but 

the new reporting guidance for non-Annex I nations is designed to facilitate 

any assessment process changes that the parties might institute in the 

future.

The Environmental Protection Agency (EPA), which is responsible for 

preparing the U.S. submission, provided clarifying comments on a draft of 

this report, which we incorporated as appropriate. We also requested 

comments from the State Department and the Framework Convention 

Secretariat, but none were provided.

Background Scientists have discovered that changes in the earth’s climate are induced 

by the increasing concentrations of certain gases in the earth’s 

atmosphere—some naturally occurring, others human-induced—that have 

the potential to significantly alter the planet’s heat and radiation balance. 

These so-called “greenhouse gases” trap some of the sun’s energy and 

prevent it from returning to space. The trapped energy warms the earth’s 

climate, much like glass in a greenhouse. Over the past century, humans 

have contributed to the greenhouse effect, particularly by burning fossil 

fuels, which increased atmospheric carbon dioxide and other greenhouse 

gases. The effects of a warmer climate could have important consequences 

for human health and welfare by, among other things, altering weather 

patterns, changing crop yields, and leading to the flooding of coastal areas.

According to the Department of Energy’s Energy Information 

Administration (EIA), in 2001, the most recent year for which data are 

available, the United States and other developed nations accounted for just 

under half (47 percent) of the world’s emissions of carbon dioxide—the 

most prevalent greenhouse gas. The other emissions came from 
Page 7 GAO-04-98 Greenhouse Gas Emissions Reports

economically developing nations, including China, India, and Mexico (40 

percent), and from nations with economies in transition (13 percent) in 

Europe and the Former Soviet Union. EIA projects that, over the next 2 

decades, carbon dioxide emissions from each of the three nation groups 

will increase; however, carbon dioxide emissions from developing nations 

will increase most dramatically, surpassing those of developed nations by 

2015, as shown in figure 1.

Figure 1: Carbon Dioxide Emissions by Developed and Developing Nations and 

Nations with Economies in Transition, 1970 through 2025, Actual and Projected

Note: The Energy Information Administration includes data on Croatia’s and Slovenia’s emissions with 

those of the developed nations, rather than with emissions data from the other nations with economies 

in transition.

Source: GAO analysis of Energy Information Administration data.

Developed nations

Developing nations

Nations with economies in transition

Actual Projected

Million metric tons

0

1,000

2,000

3,000

4,000

5,000

1970

Year

1975 1985 1995 2005 2015 2020 2025 1980 1990 2000 2010
Page 8 GAO-04-98 Greenhouse Gas Emissions Reports

More specifically, figure 2 shows actual and projected carbon dioxide 

emissions for the seven nations in our study. Growth in emissions between 

2001 and 2025 is projected to range from 29 million metric tons for the 

United Kingdom to 1,012 for China.

Figure 2: Carbon Dioxide Emissions for the Seven Nations in Our Study, Actual and 

Projected

The seven nations in our study also differ greatly in terms of their 

population and per capita income (an indicator of economic development). 

For example, population ranged from about 60 million in the United 

Kingdom to nearly 1.3 billion in China, and per capita income ranged from 

$2,540 in India to $36,300 in the United States. (See table 1.) 
Page 9 GAO-04-98 Greenhouse Gas Emissions Reports

Table 1: Comparative Statistics of the Seven Nations in Our Study

Source: Central Intelligence Agency, The World Fact Book (2002).

Notes: 

Some figures have been rounded.

Estimated per capita income is based on purchasing power parity rates. Purchasing power parity is 

based on the assumption that a unit of currency, such as a dollar, should be able to buy the same 

bundle of goods in all countries.

Nation

Estimated population,

2002 (millions)

Per capita income,

2001 or 2002

Economically developed nations

Germany 83.3 $26,600 (2002)

Japan 127.0 28,000 (2002)

United Kingdom 60.0 25,300 (2002)

United States 281.0 36,300 (2001)

Economically developing nations

China 1,284.3 4,600 (2002)

India 1,045.8 2,540 (2002)

Mexico 103.4 9,000 (2001)
Page 10 GAO-04-98 Greenhouse Gas Emissions Reports

Under the Framework Convention, the United States and the other parties 

generally agreed to implement policies and measures aimed at returning 

“individually or jointly to their 1990 levels these anthropogenic [humancaused] emissions” of greenhouse gases not covered by another treaty, the 

Montreal Protocol.5 The six primary gases covered by the Framework 

Convention are carbon dioxide, nitrous oxide, methane, and three 

synthetic gases—sulfur hexafluoride, hydrofluorocarbons, and 

perfluorocarbons. Emissions of these gases are generally not measured 

because doing so would be too costly; consequently, they must be 

estimated.6

 In this regard, the IPCC, at the parties’ request, developed 

detailed guidance on methodologies for nations to use when estimating 

their emissions and revised that guidance twice, most recently in 1999. 

Both developed and developing nations are required to follow this 

guidance—Revised 1996 IPCC Guidelines for National Greenhouse Gas 

Inventories—when preparing their inventories. In addition, in 2000, the 

IPCC published—also at the parties’ request—its Good Practice Guidance 

and Uncertainty Management in National Greenhouse Gas Inventories, 

which contains information on prioritizing tasks to arrive at the best 

possible estimates using finite resources as well as advice on establishing 

quality assurance programs, among other things. The nations have been 

encouraged, but not required, to follow the good practice guidance.

5

The Montreal Protocol, ratified by the United States in 1988, aims to reduce the use of 

substances that deplete stratospheric ozone. Among these substances are 

chlorofluorocarbons, which are also potent greenhouse gases.

6

According to EPA officials, because of the way carbon dioxide emissions are estimated, the 

results are as accurate as they would be if they were measured.
Page 11 GAO-04-98 Greenhouse Gas Emissions Reports

The parties to the Framework Convention also agreed to report 

periodically to the Secretariat on their levels of greenhouse gas emissions. 

For Annex I nations, those reports are extensive. Annually, each Annex I 

nation is required to submit inventory data—in a common reporting format 

the parties themselves agreed to—as well as a national inventory report 

that explains how the data in the common reporting format were derived. 

The common reporting format calls for data for each of the six emissions 

sectors—energy, industrial processes, solvent and other product use, 

agriculture, land-use change and forestry, and waste—as well as for the 

data on the major sources that contribute to emissions from each sector. 

The inventory data are to reflect a nation’s most recent reporting year as 

well as all previous years back to the base year, which is 1990.7

 For each 

year, the common reporting format calls for 42 tables containing over 8,100 

items that are sector-specific numbers; data summarized across sectors; 

and other information, such as trends from the base year to the current 

reporting year, recalculations of prior years’ data, and reasons certain 

emissions were not estimated. The parties require that data be submitted 

in the common reporting format to facilitate comparison across nations 

and to make it easier to review the data. Because an inventory contains 

data from the base year to the most recent reporting year, each year’s 

submission is larger than the last. The 2003 reporting format called for 

approximately 98,000 items of inventory data and other information from 

1990 through 2001. 

The national inventory report, the second component of the submission, 

should be detailed and complete enough to enable reviewers to understand 

and evaluate the inventory. The report should include, among other things, 

descriptions of the methods used to estimate the data, the rationale for 

selecting the methods used, and information about the complexity of 

methods and the resulting precision of the estimates; information on 

quality assurance procedures used; discussion of any recalculations 

affecting previously submitted inventory data; and information on 

improvements planned for future inventories. 

Each year, when Secretariat staff receive Annex I nations’ submissions, 

they perform an initial check to determine whether the submissions are 

complete and then synthesize the information to facilitate comparison 

across nations. Teams of expert reviewers—comprising members chosen 

7

Five Annex I nations with economies in transition—Bulgaria, Hungary, Poland, Romania, 

and Slovenia—are allowed to use other years as baselines.
Page 12 GAO-04-98 Greenhouse Gas Emissions Reports

by the parties for their sector expertise as well as to achieve broad 

geographic representation—also use this synthesized information to 

identify issues requiring clarification during their reviews of individual 

submissions. 

From 2000 through 2002, the parties tested the usefulness of three methods 

of conducting expert reviews on selected submissions from Annex I 

nations. The first type of review, called a desk review, consists of about 10 

experts spending about 4 weeks in their respective nations reviewing 

information on the same three nations’ inventories. For this type of review, 

the experts communicate with each other and the nation being reviewed 

via the Internet and telephone. The second type of review, called a 

centralized review, involves about 10 experts spending about a week at the 

Secretariat’s headquarters in Bonn, Germany, jointly reviewing between 

four and six nations’ inventories. The third review type, called an incountry review, consists of a team of about 5 experts spending a week in 

the nation whose inventory is being reviewed, jointly examining the 

nation’s inventory and supporting information. The Secretariat chose 

inventories of different levels of completeness to undergo desk and 

centralized reviews; only nations that volunteered for an in-country review 

received one.

During the 3-year test period, the experts examined the data and 

supporting information the nations used to prepare the inventories via all 

three types of reviews. For example, the experts determined whether a 

nation calculated its emissions estimates using formulas from published 

data sources or formulas specified by the parties. The experts also verified 

the information provided in response to questions raised in previous 

reviews. Finally, the experts summarized the inventories' strengths and 

weaknesses; made recommendations for improvement, if warranted; and 

presented their findings in reports that were both published and posted on 

the Internet. 

For Annex I nations’ submissions to be reviewed by the experts, the 

submissions must meet two criteria. Since 2000, the experts have reviewed 

only submissions that presented their data in the common reporting 

format, and, beginning with the 2003 submissions, the experts will review 

only submissions that include the national inventory report. According to 

the parties to the Framework Convention, the goal of the expert reviews is 

to identify areas in the inventories needing improvement; for this reason, 

the experts’ reports do not rate the overall quality of the submissions, and 

the reports do not identify some findings as being more important than 
Page 13 GAO-04-98 Greenhouse Gas Emissions Reports

others. According to the Secretariat, since 1998, Annex I nations’ 

submissions have steadily and substantially improved in their timeliness 

and completeness, and the expert review process has contributed to the 

improved quality of recent submissions. 

Non-Annex I nations’ requirements for format and frequency of reporting 

differ from those for Annex I nations. Although all parties to the 

Framework Convention are to develop their inventories using the revised 

1996 IPCC guidelines and submit the inventories to the Secretariat, nonAnnex I nations’ inventories are not stand-alone documents. Rather, a nonAnnex I nation’s inventory is a component of its national communication, 

which is a report it must submit to the Secretariat that discusses all of the 

steps the nation is taking or plans to take to implement the Framework 

Convention.8

 In addition, non-Annex I nations are not required to use the 

common reporting format or to submit a national inventory report. 

Moreover, non-Annex I nations are not required to submit an inventory 

each year but may instead negotiate the frequency of their submissions. To 

date, most non-Annex I nations negotiated a deadline for only one 

inventory.9

 To help the non-Annex I nations develop and report their 

inventories, the developed nations of Annex I provide financial assistance 

that is disbursed through the convention’s financial mechanism, the Global 

Environment Facility. The facility, which funds various types of 

environmental projects in developing nations,10 disburses the funds, 

including those to assist non-Annex I nations with their emissions 

reporting, through implementing agencies, such as the United Nations 

Development Program. The implementing agencies, in turn, disburse the 

funds to the nations on a schedule and according to terms negotiated by the 

agency and each nation. 

8

Annex I nations also submit national communications discussing their efforts to implement 

the Framework Convention in addition to submitting stand-alone inventories, but the format 

and frequency of the national communications are different for Annex I and non-Annex I 

nations.

9

According to the EPA official who managed the 2003 U.S. inventory, the parties to the 

Framework Convention plan to discuss increasing the frequency of non-Annex I nations’ 

inventory reporting during the next conference of the parties in December 2003.

10In addition to funding climate change projects, the Global Environment Facility also funds 

projects related to biodiversity, international waters, land degradation, ozone depletion, and 

persistent organic pollutants.
Page 14 GAO-04-98 Greenhouse Gas Emissions Reports

The inventory reviews and the extent to which the results are reported also 

differ for Annex I and non-Annex I nations. Reviews of Annex I nations’ 

submissions focus on compliance with reporting standards, and the results 

are made publicly available in considerable detail. In contrast, because 

non-Annex I nations are generally in the early stages of developing their 

inventories and have limited resources to do so, assessments of their 

submissions, and the resulting reports, focus largely on providing a forum 

for the non-Annex I nations to exchange information on common reporting 

problems and best practices. Consequently, while the Secretariat makes 

reports on the results of non-Annex I assessments publicly available, it 

does so in summary format and provides only a few nation-specific details 

in tables that accompany the aggregated reports. 

Recent Reviews Found 

That U.K. and U.S. 

Inventories Were 

Largely Complete, but 

German and Japanese 

Inventories Lacked 

Critical Elements

The most recent expert reviews of inventories submitted by the four 

developed nations found that the U.K. and U.S. inventories contained most 

of the required elements, but the German and Japanese inventories were 

missing certain critical elements. Experts reviewed inventories variously 

submitted from 2000 through 2002 by each of the four developed nations in 

our study. The inventories submitted by Japan and Germany in 2000 and 

2001, respectively, each received a centralized review. Two U.K. inventories 

were reviewed: the one submitted in 2000 received an in-country review, 

and the one submitted in 2002 received a desk review. The inventory that 

the United States submitted in 2000 received both an in-country review and 

a desk review. Although the experts planned to conduct reviews of all 

Annex I nations’ inventories submitted in 2003, no results were available at 

the time of our study.

The reviews of the submissions of the United Kingdom and the United 

States found they were largely complete and noted only relatively minor 

problems. For example, the reviews of the two nations’ 2000 submissions 

noted that neither submission included information on quality assurance 

procedures. Although the good practice guidance calls for including such 

information in the national inventory report, the nations were encouraged, 

but not required, to follow the good practice guidance for the 2000 

submissions. Nonetheless, the experts included the lack of quality 

assurance documentation as a finding of the reviews. Because the 

problems noted were relatively minor, the suggestions for improving future 

submissions constituted refinements rather than recommendations for 

large-scale changes. For example, the experts’ report on the 2000 U.K. 

submission suggested archiving the documentation supporting the national 

inventory report in one location or on the Web. Similarly, the report on the 
Page 15 GAO-04-98 Greenhouse Gas Emissions Reports

desk review of the 2000 U.S. submission suggested that more details on the 

methods and factors used to estimate emissions for the land-use change 

and forestry sector would allow more complete assessment of that sector’s 

data.

In contrast, the reviews of the German and Japanese submissions found 

them to be missing some critical components, and the experts’ reports 

made suggestions for improvement that were fundamental in nature. For 

example, the review of Germany’s 2001 submission found it contained only 

summary-level and trend data; it did not include any of the sector-specific 

data tables or recalculations of prior years’ data called for by the common 

reporting format. Furthermore, the national inventory report was missing, 

so the reviewers could not determine whether problems noted in previous 

inventories had been addressed. Although the review of the Japanese 2000 

submission found most of the data required by the common reporting 

format was included, like the German submission, this one lacked the 

national inventory report. As a result of these shortcomings, the experts 

suggested that Germany submit a complete set of data for all of the 

required years and sectors and that both nations submit the national 

inventory report. Additional details on the findings of the six expert 

reviews are contained in appendix I.

Although none of the four Annex I nations’ latest submissions—for 2003—

had undergone an expert review as of November 2003, Secretariat staff had 

performed initial completeness checks on each of them. They found that all 

four nations’ submissions contained most of the required data as well as 

the required national inventory reports. 

Little Nation-Specific 

Inventory Information 

Is Available for the 

Three Developing 

Nations

The Secretariat has not assessed any inventories from China and India 

because, as of November 2003, neither nation had submitted one. The 

Secretariat assessed Mexico’s 2001 submission, but the Secretariat’s 

practice is to issue one report on the findings of its assessments of all the 

inventories submitted during the year, with few nation-specific details. 

Therefore, the Secretariat made public little information about the results 

of its assessments that could be directly tied to Mexico.

According to the Secretariat, China and India are preparing their initial 

inventories, to be submitted as part of their first national communications. 

Under article 12, paragraph 5, of the Framework Convention, non-Annex I 

nations’ first inventories are due to the Secretariat “within three years of 

the entry into force of the Framework Convention or of the availability of 
Page 16 GAO-04-98 Greenhouse Gas Emissions Reports

financial resources” from the developed nations in Annex I. According to 

the Secretariat, funding was approved for China in May 2000 and for India 

in December 1999, and the first disbursements of funds took place in 

November 2001 for China and in July 2001 for India. According to the 

Secretariat, the due dates for their first greenhouse gas inventories are no 

later than November 2004 for China and July 2004 for India. 

Mexico submitted inventories in 1997 and 2001. Although 106 developing 

nations had submitted their initial inventories as of November 2003, 

Mexico is the only nation to have submitted more than one. Secretariat 

staff assessed Mexico’s 2001 inventory, along with those of 51 other nonAnnex I nations that submitted inventories that year. In keeping with its 

practice of reporting on its assessments of non-Annex I nations’ inventories 

as a group, the report for 2001 contained only limited details that could be 

linked specifically to Mexico’s inventory. In particular, the Secretariat 

reported that Mexico had improved its estimates of emissions from the 

energy, agriculture, and land-use change and forestry sectors. It also 

reported that Mexico could further improve its inventory by establishing 

systematic procedures for preparing the inventory annually and by 

including estimates for the solvent-use sector. Otherwise, the Secretariat 

reported only generally on the results of the assessments of submissions of

the 52 non-Annex I nations’ inventories.

Mexico’s 2001 submission contained estimates for 1994, 1996, and 1998. 

According to an EPA official who is knowledgeable about Mexico’s 

inventory, the 2001 Mexico inventory is of reasonably high quality, 

especially considering the limited resources Mexico has dedicated to 

developing it. According to its submission, Mexico followed the IPCC 

estimating guidelines and good practice guidance in preparing the 

inventory. The EPA official further commented that Mexico’s 2001 

submission is among the best of those of the developing nations, and in 

some cases—for example, in presentation of its carbon dioxide emissions 

data—is equal to those of some developed nations. On the other hand, 

according to that official, Mexico did not (1) comply with the IPCC 

estimating guidelines in developing the land-use change and forestry sector 

data, (2) adequately estimate data for the three synthetic gases, or (3) 

provide adequate documentation explaining the inventory. Furthermore, 

Mexico developed its two inventories independent of each other, without 

establishing a process that would systematically make documentation and 

data additions and revisions as needed. Consequently, in the opinion of the 

EPA official, it was difficult for Mexico to build upon its previous efforts 

when preparing its second inventory.
Page 17 GAO-04-98 Greenhouse Gas Emissions Reports

The Four Developed 

Nations Reported 

Generally High 

Confidence in Their 

Latest Emissions Data, 

but Future 

Assessments of 

Confidence Must Be 

More Precise

As required for the 2003 submissions, the four developed nations 

categorized their confidence in their emissions data as either high, medium, 

or low. All four nations reported their confidence in the data as generally 

high. To improve the usefulness of nations’ assessments of data confidence, 

however, beginning with the 2004 submissions, developed nations must 

quantify their confidence assessments. 
Page 18 GAO-04-98 Greenhouse Gas Emissions Reports

The Four Developed 

Nations Rated Their 

Confidence in Their Most 

Recent Emissions Data as 

Generally High

As previously explained, the parties to the Framework Convention have 

constructed an extensive system of estimating and reporting requirements, 

buttressed by periodic reviews, to help nations produce inventory data that 

are of high quality. The parties do not attempt, on the basis of the reviews 

or any other means, to assign a grade or otherwise rate any nation’s success 

in producing high-quality data. However, as one means of helping 

developed nations identify areas where their data can be strengthened, the 

parties require each nation to assess its confidence in the accuracy of its 

own data. Specifically, the nations are required annually to analyze the 

quality of the data they report (called an uncertainty analysis) for each gas 

and for each major source of emissions and removals in each of the six 

sectors. To do this, the nations have been encouraged, but not required, to 

use the quantitative methods of uncertainty analysis included in the IPCC 

good practice guidance. Alternatively, they could rely on qualitative means 

to determine their confidence in these data. In either case, they have been 

required to report whether they had high, medium, or low confidence in 

each estimate of emissions of each of the six gases by each major source of 

those emissions. The nations have not been required to report on their 

confidence in the accuracy of the inventory data as a whole. The parties did 

not provide further criteria for nations to use when determining which of 

the three categories was most appropriate.11 

11According to EPA officials, the confidence a nation has in the accuracy of its inventory 

depends on the predominant sources of its emissions, as well as on the completeness of the 

inventory and the quality of the methods it uses to estimate emissions. For example, a 

nation such as New Zealand, whose greenhouse gas emissions’ sources are predominantly 

in the agriculture and land-use change and forestry sectors, may have lower confidence in 

the accuracy of its inventory data as a whole than a nation such as the United States, whose 

emissions originate predominantly from the energy sector, even though both nations might 

be using state-of-the-art estimation methods. This is because emissions estimates from the 

agriculture and land-use change and forestry sectors are inherently less accurate than those 

originating from fossil fuels that produce energy.
Page 19 GAO-04-98 Greenhouse Gas Emissions Reports

As required, all four developed nations reported high, medium, or low 

ratings of confidence in their estimates for their 2001 emissions by source. 

To determine the confidence each nation had in its inventory data as a 

whole, we calculated the proportion of each nation’s data that 

corresponded to each of the three rating categories. According to our 

calculations, all four nations rated their confidence in their inventory data 

as a whole as generally high, with the high-confidence ratings ranging from 

about 75 percent for the United States to about 96 percent for Japan. The 

high-confidence ratings occurred largely because the lion’s share of each 

nation’s total emissions is carbon dioxide from fuel combustion, which can 

be estimated with a relatively high level of confidence. Table 2 shows each 

nation’s ratings for total emissions by gigagrams of carbon dioxide 

equivalent, which is the unit of measurement used by the parties to the 

Framework Convention to allow comparisons among greenhouse gases, 

which differ in their effects on the atmosphere and expected lifetimes.

Table 2: Four Developed Nations’ Ratings of Confidence in Their Data for Total Emissions in 2001

Source: GAO analysis of data from the four nations’ 2003 submissions to the Framework Convention Secretariat.

Notes: 

Percentages do not total to 100 because of rounding.

In compiling this table, to fully report the nations’ ratings for the six gases, we added the amount of 

removals to the amount of gross emissions; consequently, the data in the table do not match the net 

emissions reported by the nations.

a

Percentage is less than .005 and rounds to 0.

Although the national inventory reports contained some information about 

the nations’ confidence in their data, none of the nations explained the 

criteria they used to determine the high-, medium-, and low-confidence 

ratings they reported.

Gigagrams of carbon dioxide equivalent

Developed nations’ ratings of confidence for total emissions

Nation

Amount 

rated high

Percentage 

rated high

Amount 

rated 

medium 

Percentage 

rated medium

Amount 

rated low

Percentage 

rated low

Amount 

not rated

Percentage 

not rated

Germany 948,175 93.1 59,054 5.8 7,982 0.8 3,817 0.4

Japan 1,244,048 95.7 20,056 1.5 35,326 2.7 15 0a

United 

Kingdom 561,274 82.9 53,907 8.0 62,036 9.2 12 0a

United 

States 5,670,596 72.9 1,462,157 18.8 567,775 7.3 73,816 1.0
Page 20 GAO-04-98 Greenhouse Gas Emissions Reports

Developed Nations Must 

Use Quantitative Methods to 

Assess Their Confidence in 

Their Data in 2004

In November 2002, the parties decided to require developed nations to use 

the quantitative methods in the IPCC good practice guidance to develop 

estimates of data uncertainty beginning with the 2004 submissions. Instead 

of designating high, medium, or low ratings of confidence, under the new 

requirements, developed nations must quantify their uncertainty in their 

emissions estimates for each gas by each major source using 95 percent 

confidence levels. In addition, they must combine the source uncertainty 

estimates into a quantified uncertainty estimate for the inventory as a 

whole and estimate the uncertainty in the trend between the base year and 

the most recent year. 

The IPCC good practice guidance provides detailed instructions for nations 

to follow to produce the quantitative estimates of data uncertainty. The 

guidance also describes two methods for combining quantitative 

uncertainty estimates—one consisting of relatively simple statistical 

calculations that result in a numerical uncertainty estimate, and the other 

using computer simulation to calculate the estimates. The computer 

simulation is a more sophisticated method and should result in more 

accurate estimates; however, according to the EPA official responsible for 

compiling the U.S. inventory, the computer simulation also is more costly 

than the simpler method. Because of this, the good practice guidance states 

that the nations must use the simpler of the two methods to produce their 

combined uncertainty estimates; in addition, they are encouraged to use 

the more sophisticated method when sufficient resources and expertise are 

available. 

For example, in its 2003 inventory submission, the United Kingdom used 

both methods from the good practice guidance to quantitatively estimate 

its confidence in its 2001 emissions data as a whole. Using the simpler 

method, the United Kingdom reported an uncertainty value of 17 percent 

for its inventory data as a whole; that is, the United Kingdom was 95 

percent confident that total emissions were between 17 percent less and 17 

percent more than the total of about 660,452 gigagrams of carbon dioxide 

equivalent it estimated for the year. In contrast, using the more 

sophisticated method, the United Kingdom reported an uncertainty value 

of 13 percent, indicating it was 95 percent confident that total emissions 

were between 13 percent less and 13 percent more than the year’s total 

estimate.

According to the EPA official responsible for compiling the 2003 U.S. 

inventory, the high, medium, and low categorizations reflect the early days 

of developing inventories, before the IPCC had developed its good practice 
Page 21 GAO-04-98 Greenhouse Gas Emissions Reports

guidance on quantitative methods. Prior to the guidance, the parties 

recognized that nations would vary in their ability to perform quantitative 

uncertainty analysis. The parties instituted the three-part categorization in 

an effort to obtain information that was comparable across nations that 

were using different methods for assessing data uncertainty. The parties 

have moved to the quantitative methods because the three-part 

categorization approach yielded limited information about data 

uncertainty. For example, a nation could have uncertainty estimates of 35 

percent and 60 percent but could have categorized both estimates as 

medium. The quantitative estimates provide information about the 

uncertainty of the various components of the inventory, thereby helping 

nations identify areas in which improvements would have the greatest 

effect on the accuracy of the inventory as a whole. In addition, the 

quantified estimates make the uncertainty analyses more consistent and 

understandable across nations. According to the Secretariat, the quantified 

uncertainty analysis also better enables expert reviewers to determine if 

nations are targeting their improvements in the appropriate areas.

The Parties Are Taking 

Steps to Improve the 

Quality of Emissions 

Data

To improve the quality of data on greenhouse gas emissions, the parties to 

the Framework Convention are refining their requirements for both Annex 

I and non-Annex I nations. In addition, they are bolstering the review 

processes for Annex I nations. The changes are to begin to take effect over 

the next few years. The parties currently have no plans to change the way 

that non-Annex I nations’ inventories are assessed. 

Changes in Requirements 

for Annex I and Non-Annex 

I Nations Take Effect over 

the Next Few Years

The parties have revised their requirements for both Annex I and nonAnnex I nations, with the changes taking effect over the next few years. 

The revisions fall mainly into two areas: procedures for estimating 

emissions and procedures for reporting those estimates. 

The parties have revised both the estimating and reporting requirements 

for Annex I nations. Regarding estimating, for example, beginning with the 

2004 submissions, Annex I nations will be required to use both the 1996 

IPCC estimating guidelines and the 2000 IPCC good practice guidance. 

Previously, Annex I nations were required to use only the 1996 estimating 

guidance and were encouraged, but not required, to use the good practice 

guidance. Regarding reporting, the parties have specified in greater detail 

than before the information that should be included in Annex I nations’ 

national inventory reports and in the data tables in the common reporting 
Page 22 GAO-04-98 Greenhouse Gas Emissions Reports

format. For example, nations should include explanations of how they 

recalculated their previous years’ data and, as previously discussed, the 

methods they used to quantify their confidence in the data in their national 

inventory reports. In their reports, nations should document that they 

prepared their estimates in accordance with the IPCC good practice 

guidance or explain why they did not; for example, an explanation is 

required if they used a more sophisticated methodology than that specified 

in the guidance. The nations should also cross-reference the information in 

the national inventory report to explain the estimates reported in the data 

tables. Furthermore, Annex I nations must submit their national inventory 

reports following a specified format designed to facilitate review of the 

inventories. 

The parties also revised the reporting requirements for non-Annex I nations 

that submit inventories in 2003 or later. Non-Annex I nations that had not 

submitted an inventory prior to 2003 must include data in their initial 

inventories for either 1990 or 1994 to establish an inventory baseline. Those 

submitting their second inventories should provide data for 2000 as well. 

This is in contrast to the requirement that Annex I nations submit data for 

all years, from 1990 to the present. Similarly, the parties specified that nonAnnex I nations should report data for carbon dioxide, methane, and 

nitrous oxide and encouraged reporting of the other three gases—

hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride. In 

contrast, Annex I nations are required to report data for all six gases. 

According to the manager of the 2003 U.S. inventory, the estimating and 

reporting requirements for non-Annex I nations are less demanding to 

encourage those nations to report because those nations generally have 

fewer resources available for reporting.

In addition, the parties have requested that the IPCC continue to improve 

its guidance on estimating. Currently, the good practice guidance does not 

address estimating emissions and removals for the land-use change and 

forestry sector. According to the EPA official who managed the 2003 U.S. 

inventory, the IPCC deferred guidance on estimating emissions and 

removals because it was developing a special report on them, which was 

subsequently published in 2000. On the basis of that report, the IPCC began 

drafting new good practice guidance for estimating emissions and removals 

for the land-use change and forestry sector, which is due to be completed in 

late 2003. As part of this effort, the IPCC is also refining the data tables for 

the land-use change and forestry sector. In addition, according to the same 

EPA official, the IPCC is merging the 1996 guidelines with its good practice 

guidance and expects to complete the effort by 2007. 
Page 23 GAO-04-98 Greenhouse Gas Emissions Reports

The Parties Are Bolstering 

the Review Process for 

Annex I Nations, but Not for 

Other Nations

The parties are strengthening the expert review process for Annex I 

nations’ submissions by conducting more reviews and standardizing the 

review processes. Beginning with the 2003 submissions, each of the 39 

Annex I nations will undergo one of the three types of expert reviews each 

year: an in-country review once every 5 years and either a desk review or a 

centralized review in each of the intervening years. This requirement 

contrasts with the practices of the past 3 years, when the experts 

performed from 8 to 21 expert reviews in a year. Furthermore, to 

standardize the reviews, the parties have spelled out, in greater detail than 

before, the elements that are to be examined during reviews and have 

developed a standardized format for reporting the results of the reviews. In 

addition, according to EPA inventory managers, in another effort to make 

the expert reviews more uniform, the Secretariat is developing a handbook 

and a training program for the expert reviewers and has specified the 

composition and responsibilities of the teams of expert reviewers. 

According to the Secretariat, the parties have no plans to change the 

assessment process for non-Annex I nations’ inventories, but the new 

reporting guidance for non-Annex I nations would facilitate changes to the 

assessment process, should the parties decide to institute them.

Scope and 

Methodology

To examine the results of the most recent expert reviews of the greenhouse 

gas inventories submitted by the four economically developed nations 

included in our study—Germany, Japan, the United Kingdom, and the 

United States—we reviewed and analyzed the Secretariat’s status reports 

showing the results of its initial reviews (called stage 1 reviews by the 

Secretariat) of the most recently submitted inventories (2003). We also 

reviewed the reports on the parties’ most recent expert reviews (called indepth reviews by the Secretariat) of the four nations’ inventories (2000 for 

Japan, 2000 and 2002 for the United Kingdom, 2000 for the United States, 

and 2001 for Germany) and related documentation on reporting 

requirements and review processes issued by the Secretariat. We 

interviewed officials at EPA who manage the U.S. greenhouse gas inventory 

and serve as inventory experts for the parties, as well as officials from the 

State Department’s Bureau of Oceans and International Environmental and 

Scientific Affairs who are responsible for policy issues related to the 

Framework Convention. In addition, we reviewed and analyzed the limited 

information provided to us by the Secretariat in response to questions we 

posed.
Page 24 GAO-04-98 Greenhouse Gas Emissions Reports

To describe the results of any assessments of inventories of the three 

developing nations included in our study—China, India, and Mexico—we 

reviewed and analyzed the Secretariat’s reports on its assessments of 

inventories submitted by non-Annex I nations, including the latest 

inventory submitted by Mexico (2001); related documentation on nonAnnex I nation reporting requirements and assessment processes; and 

other Secretariat information documenting which non-Annex I nations 

have submitted inventories. We also interviewed the officials at EPA and 

the Department of Energy who are most familiar with the three nations’ 

efforts to compile and report their inventories, as well as the cognizant 

officials from the State Department. 

To determine the extent to which the developed nations have confidence in 

their data, we analyzed the confidence information each nation provided in 

its 2003 submission. To describe any changes in assessing confidence in the 

data that are to take effect in the future, we examined documentation from 

the Secretariat and the relevant sections of the four developed nations’ 

2003 submissions.

To describe the steps the parties are taking to improve the quality of future 

inventory data and determine when those improvements might be in place, 

we reviewed and analyzed documentation of the parties’ new estimating, 

reporting, and review requirements; interviewed cognizant EPA officials; 

and reviewed and analyzed the limited information on this issue submitted 

to us by the Secretariat in response to questions we posed. 

We performed our work between November 2002 and November 2003 in 

accordance with generally accepted government auditing standards.

Agency Comments We provided a draft of this report to the Secretary of State, the 

Administrator of EPA, and the Framework Convention Secretariat for 

review and comment. EPA provided clarifying comments, which we 

incorporated where appropriate. We did not receive comments from the 

State Department or the Framework Convention Secretariat.

As arranged with your offices, we plan no further distribution of this report 

until 30 days after the date of this letter, unless you publicly announce its 

contents earlier. At that time, we will send copies of this report to 

interested congressional committees; the Chairmen and Ranking Minority 
Page 25 GAO-04-98 Greenhouse Gas Emissions Reports

Members, Senate Committee on Appropriations, House Committee on 

Appropriations, Senate Committee on Governmental Affairs, and House 

Committee on Government Reform; the EPA Administrator; and the 

Secretary of State. We will make copies available upon request to other 

interested parties. This report will also be available at no cost on GAO’s 

Web site at http://www.gao.gov.

If you or your staffs have any questions about this report, please call me at 

(202) 512-3841. I can also be reached at stephensonj@gao.gov. Key 

contributors to this report are listed in appendix II.

John B. Stephenson

Director, Natural Resources 

and Environment
Page 26 GAO-04-98 Greenhouse Gas Emissions Reports

Appendix I

Results of Expert Reviews of the Four Apendxies

Developed Nations’ Inventories ApendxiI

The six expert review reports we examined did not follow identical 

formats; however, they generally highlighted the experts’ findings and 

suggestions for improvement in a summary section at the beginning of each 

report. The experts noted instances of noncompliance with the reporting 

requirements. In addition, the experts noted some instances in which the 

nations did not comply with the Good Practice Guidance and Uncertainty 

Management in National Greenhouse Gas Inventories, even though 

following the good practice guidance was not a requirement at the time that 

the inventories were submitted. The summary-level findings and 

suggestions for each of the six expert reviews we examined are listed in 

table 3. 
Appendix I

Results of Expert Reviews of the Four 

Developed Nations’ Inventories

Page 27 GAO-04-98 Greenhouse Gas Emissions Reports

Table 3: Results of the Most Recent Expert Reviews of the Four Developed Nations’ Inventories

Expert review Findings Suggestions for improvement

Centralized review of 

Germany’s inventory 

submitted in 2001

Inventory did not conform to Secretariat’s guidelines; 

specifically, it did not include the following: 

• sector-specific data,

• a national inventory report,

• required information on major sources of emissions,

• recalculated data for previous years or explanation of 

recalculations,

• quantitative uncertainty estimates nor a qualitative 

discussion of reasons for uncertainty,

• procedures on quality assurance, 

• inventory in specified software format,

• information on how the nation develops and manages its 

inventory, and 

• information on ongoing efforts to improve the quality of 

its inventory.

Inventory was submitted after the deadline.

Inventory did not include information on any 

improvements made in response to problems identified 

with previous inventories.

Submit national inventory report with a brief 

explanation of methodologies and 

underlying assumptions that were used to 

compile the inventory.

Compile a complete emissions inventory for 

all of the required years and sectors.

Centralized review of Japan’s

inventory submitted in 2000

Inventory did not conform to Secretariat’s guidelines; 

specifically, it did not include the following:

• a national inventory report and

• recalculated data for previous years.

 

Inventory did not contain information needed to determine 

completeness of sources of emissions for the industrial 

processes sector.

Improve documentation.

Submit a national inventory report to explain 

methods used to estimate emissions. 

Improve the consistency of the data and 

information provided. 

In-country review of the United 

Kingdom’s inventory 

submitted in 2000

Inventory did not completely conform to Secretariat’s 

guidelines; specifically, the United Kingdom did not

• provide the national inventory report on time;

• apply the Secretariat’s good practice guidance;

• provide required details for the waste and the land-use 

change and forestry sectors;

• include required calculations and disaggregated activity 

data for the sectors;

• explain rationale for assumptions used for emission 

estimates;

• use consistent assumptions and methods to report timeseries information for sources of emissions in the 

industrial processes sector;

• include information on quality assurance procedures; 

and

• include required information on sources of and methods 

for estimating hydrofluorocarbons, perfluorocarbons, 

and sulfur hexafluoride. 

Archive documentation supporting the 

national inventory report in one location or 

on the Web.

Publish findings from research on improving 

estimates.

Perform quality assurance procedures for 

emissions data from industry. 

Report emissions and removals separately.
Appendix I

Results of Expert Reviews of the Four 

Developed Nations’ Inventories

Page 28 GAO-04-98 Greenhouse Gas Emissions Reports

Source: GAO analysis of expert reviews.

Desk review of the United 

Kingdom’s inventory 

submitted in 2002

No findings were noted. Attempt to include estimates for data 

categories not yet included.

Provide more specific information in the 

national inventory report on how the 

consistency of emissions data over time was 

achieved.

Desk review of the United 

States’s inventory submitted in 

2000

The information included in the data tables was somewhat 

inconsistent with the information included in the national 

inventory report.

The data tables did not include recalculations; however, 

the national inventory report included information on 

revised methodologies and updated data that were used 

for recalculations.

The inventory did not include information on the quality 

assurance procedures that were used.

 

The inventory did not include information on the quality of 

estimates in the data tables.

For more complete and transparent 

reporting in the land-use change and 

forestry sector,

• include a description of methods used for 

estimating carbon dioxide removals in 

forest soils and landfills;

• provide more explanation on factors used 

to estimate carbon dioxide removals in the 

forest floor, understory vegetation, and 

harvested wood products; and 

• include data on emissions and removals 

from abandonment of managed lands and 

nonforest organic mineral soils.

In-country review of the United 

States’s inventory submitted in 

2000

The information included in the data tables was somewhat 

inconsistent with the information included in the national 

inventory report.

The data were estimated using complex methods and 

models that required data at a more detailed level than 

was provided.

Although the national inventory report contained some 

information on quantitative and qualitative indications of 

uncertainties for emissions sources, the estimates were 

not complete.

The national inventory report provided no specific 

information on verification and quality assurance 

procedures. 

Apply quality assurance procedures to all 

sectors.

(Continued From Previous Page)

Expert review Findings Suggestions for improvement
Page 29 GAO-04-98 Greenhouse Gas Emissions Reports

Appendix II

GAO Contacts and Staff Acknowledgments ApendxiI

GAO Contacts John B. Stephenson, (202) 512-3841

David Marwick, (202) 512-6775

Staff 

Acknowledgments

In addition to the individuals named above, Simin Ho and Karla Springer 

made key contributions to this report. Nancy Crothers, Sandra Edwards, 

Barbara Johnson, Karen Keegan, Andria Key, Charlotte Moore, Chris 

Moriarity, Katherine Raheb, and Anne Rhodes-Kline also made important 

contributions.

(360277)
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Web site: www.gao.gov/fraudnet/fraudnet.htm

E-mail: fraudnet@gao.gov

Automated answering system: (800) 424-5454 or (202) 512-7470

Public Affairs Jeff Nelligan, Managing Director, NelliganJ@gao.gov (202) 512-4800

U.S. General Accounting Office, 441 G Street NW, Room 7149 

Washington, D.C. 20548
United States

General Accounting Office

Washington, D.C. 20548-0001

Official Business

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