Last reviewed on June 6, 2017

1990 to 2004 Inventory Data and Documentation

Illustration of a document archive with drawers for each greenhouse gas
GHG inventory archive


This is the first edition of California's GHG inventory published by the ARB in November 2007. The 1990-2004 GHG inventory provided the 1990 emission level which became the 2020 GHG limit pursuant to the California Global Warming Solutions Act (AB 32). Since the first inventory edition, ARB has annually updated the GHG inventory with current year data and improved methodology. The current year inventory can be found in this page.

The original 1990-2004 inventory was based on the global warming potential (GWP) values in the Intergovernmental Panel on Climate Change (IPCC) Second Assessment Report (SAR). IPCC periodically updates GWP values with improved scientific understanding of the intensity of infrared absorption by each GHG and how long the GHG remain in the atmosphere. For each annual update of the inventory since 2014, ARB has been using the GWP values from the IPCC Fourth Assessment Report (AR4) consistent with current international and national GHG inventory practices. The original 1990-2014 inventory has been converted from SAR to AR4 GWPs (but has not been recalculated based on the updated methodology and data sources employed by more recent inventory editions). This webpage presents the inventory based on AR4 GWPs and continues to make available the original inventory in SAR GWPs for archival purposes.

The GHG emissions and sinks are categorized in two ways:

  1. Process-oriented categories; follows the IPCC categorization to ensure consistency and comparability with international inventories.
  2. Economic sectors; enables comparison with other ARB emission inventories, which are similarly categorized.

1990-2004 Inventory Data

Query the 1990 inventory (AR4 GWPs)

bullet Query the 1990 inventory by economic sector and/or by activity. This interactive query tool allows you to select a subset of the inventory in a table, view it or download it to your computer, find out how each of the emissions values was estimated, and plot the data. The query outputs are shown in AR4 GWPs. More details on the query tool's help page.

Download the entire 1990-2004 inventory (AR4 GWPs)

Download a Summary of the 1990-2004 Inventory (AR4 GWPs)

Download the entire 1990-2004 inventory (SAR GWPs)

Download a Summary of the 1990-2004 Inventory (SAR GWPs)


Go To Detailed Documentation Index (SAR GWPs)

bullet Interactive documentation index by IPCC category