INTRODUCTION TO THE
REFERENCE MANUALThis Reference Manual is one of three volumes of the Revised 1996 IPCC Guidelines for
National GHG Inventories. It provides a compendium of information on the various humanactivities which cause greenhouse gas emissions or removals to occur. It builds on work
carried out in preparation of:• OECD Report: Estimation of Greenhouse Gas Emissions and Sinks, Final Report From theOECD Experts Meeting, 18-21 February 1991, (OECD, 1991).
• Proceedings of an International IPCC Workshop on Methane and Nitrous Oxide, Amersfoort,NL, 3-5 February 1993 (van Amstel, 1993).
• 1995 IPCC Guidelines.
In preparing this document, the IPCC/OECD/IEA has also received valuable technicalinput from a number of international workshops and IPCC Expert Group Meetings. The
overall purpose of these workshops was to provide a forum for experts to discuss ways
to improve the methodologies and reporting procedures and to ensure widespreadparticipation in the development process. Many of the recommendations received havebeen incorporated into this revised Reference Manual.
In general, the basic approach to estimating national emissions is similar across thevarious gases and human activities which are sources or sinks. Fundamentally, emissions
are a product of activity data and emission factors. In reality, these calculations are often
more complicated than this would indicate, with several steps being involved in thecalculation of each of the general terms - activity data and emission factors. But it is useful
to keep this general structure in mind as it provides an organising framework for all of
the calculations and a means of evaluation and comparison.
The Reference Manual frequently provides a number of different possible methodologies
or variations for calculating a given emission. In most cases these represent calculations of
the same form but the differences are in the level of detail at which the original
calculations are carried out. Wherever possible the methodology provides a "tiered"structure of calculations which describes and connects the various levels of detail at which
national experts can work depending on the importance of the source category,
availability of data, and other capabilities. All national experts are encouraged to work at
the most detailed level which is possible and appropriate for their situation. The tieredstructure ensures that estimates calculated at a very detailed level can be aggregated up
to a common minimum level of detail for comparison with all other reporting countries.

Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories:

Reference Manual

INTRODUCTION.1

INTRODUCTION

The methodologies for the estimation of the emissions and removals of GHGs, which arepresented and discussed in the Guidelines, are grouped by the main activity sectors,(chapters of this volume) namely, Energy, Industrial Processes, Solvent and Other Product Use,Agriculture, Land Use Change and Forestry, and Waste. In general, the source/sink activities
are unique to their sector but there are cases, e.g., biomass burning, which occur inseveral sectors and are described in the chapters on Land-Use Change and Forestry, Energyand Agriculture.
The chapters are divided by subject areas and correspond to the same subject chapters inthe Workbook. This document should be used by national experts as a reference tool toaccompany the Workbook and the Reporting Instructions when constructing and reporting
national inventories of GHG emissions and removals.

References
OECD (1991), Estimation of Greenhouse Gas Emissions and Sinks, Final Report from theOECD Experts Meeting, 18-21 February 1991. The Organisation for Economic
Co-operation and Development, Paris, France, revised August 1991.
van Amstel, A.R. (ed.) (1993), Proceedings of an International IPCC Workshop on Methane
and Nitrous Oxide: Methods in National Emissions Inventories and Options for Control,
Amersfoort, NL. 3-5 February 1993. RIVM Report No. 481507003, Bilthoven,
The Netherlands, July.
IPCC/OECD/IEA (1995), IPCC Guidelines for National Greenhouse Gas Inventories,
IPCC/OECD/IEA Inventory Programme, Paris, FranceINTRODUCTION.2

Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories: Reference Manual