The GHG Protocol Corporate Accounting and Reporting Standard helps companies and other organizations to identify, calculate, and report GHG emissions. It is designed to set the standard for accurate, complete, consistent, relevant and transparent accounting and reporting of GHG emissions.

As a signatory to the United Nations Framework Convention on Climate Change, Canada is obliged to submit an inventory of its greenhouse gas (GHG) emissions on an annual basis. This document provides an overview of Canada's GHG inventory for the period 1990-2003. It describes trends in GHG emissions and removals in the following sectors: electricity & petroleum industries; transportation; mining & manufacturing industries; solvent & other product use; the residential, commercial, & institutional sector; agriculture; land use, land-use change, & forestry; and waste management. The document also includes a summary of provincial & territorial GHG emissions by sector.

This report represents Canada's official greenhouse gas inventory submission to the United Nations Framework Convention on Climate Change. It also contains, where possible, relevant supplementary information (including a summary of appropriate methodologies, definitions, emission estimates and emission factors that were used in developing the national & provincial estimates) and an analysis of recent trends in emissions and removals. The inventory is arranged by source sector: energy (fuel combustion, fugitive emissions), industrial processes (minerals, chemicals, metals, other), solvent & other product use, agriculture, land use change & forestry, and waste (disposal on land, waste water handling, incineration, composting). Appendices include an emission summary, detailed methodologies, and data tables.

Urbanization drastically alters the ecosystems structure and functions, disrupts cycling of C and other elements along with water. It alters the energy balance and influences climate at local, regional and global scales. In 2008, urban population exceeded the rural population. In 2050, 70% of the world population will live in urban centers. The number of megacities (10 million inhabitants) increased from three in 1975 to 19 in 2007, and is projected to be 27 in 2025. Rapid urbanization is altering the ecosystem C budget. Yet, urban ecosystems have a large C sink capacity in soils and biota. Judicious planning and effective management can enhance C pool in urban ecosystems, and off-set some of the anthropogenic emissions. Principal components with regards to C sequestration include home lawns and turfs, urban forests, green roofs, park and recreational/sports facilities and urban agriculture.

Of the emissions of carbon dioxide, methane, nitrous oxide and chlorofluorocarbons released to the environment in Canada in 1990 by source, sector, province and fuel type. The report also describes the methods used to develop the emission estimates and their limitations. Sources for the estimates include published reports and scientific papers, mass balance, engineering calculations and engineering judgement.

This report begins with an overview of climate change and Canada's commitments under the Framework Convention on Climate Change, then reviews national characteristics affecting greenhouse gas emissions, the national greenhouse gas inventory, and policies & measures under the National Action Program on Climate Change. This is followed by chapters covering: a national projection of greenhouse gas emissions to 2020; possible impacts of climate change on Canada, including implications for water resources, health, agriculture, and forestry, as well as Canadian initiatives regarding adaptation to climate change; financial assistance & technology transfer activities related to climate change, including international initiatives; research & monitoring activities related to climate change; and education, training, & public awareness initiatives. Appendices include summaries of federal & provincial/territorial policies & measures affecting greenhouse gas emissions, by sector.