|
|
Regional CAP Inventory Emissions Lookup Tool
Introduction
The Air District developed the regional CAP Emissions Inventory Lookup Tool to provide an interactive way to explore the Bay Area’s Criteria Air Pollutant (CAP) emissions inventory from 1990 through 2040. The tool allows users to:
- View regional emissions: Explore total emissions by pollutant and sector for any year from 1990 through 2040.
- Explore sector and subsector emissions: See a more detailed breakdown of emissions by pollutant, sector, and subsector.
- Explore emissions over time: View time series showing how emissions from individual subsectors change over time and their contribution to overall sector emissions.
All emissions displayed in the tool are reported in units of tons per year (tpy). Emissions from biogenic (natural) sources are estimated in the inventory but not included in the visual display tool.
Regional CAP Emissions Inventory Lookup Tool
How To Use
The steps below provide instructions for using the emissions lookup tool to explore the Bay Area’s regional CAP emissions inventory:
- Select a pollutant from the horizontal menu under ‘Step 1. Select a Pollutant’.
- Next, select a year between 1990 to 2040 under ‘Step 2. Select Year’.
- The pie charts will automatically update to display the annual Bay Area emissions based on the selection in Steps 1 and 2.
- The ‘Emissions by Sector’ displays the distribution of emissions across the five major sectors. The ‘Emissions by Sub Sector’ shows the distribution of emissions across individual subsectors, from largest to smallest contributor. Subsector emissions can be viewed by hovering over any portion of the chart or shown in tabular format by right clicking anywhere on the chart and then clicking the ‘Show as a table’ option.
- To view how emissions change over time, select ‘Go to Sector timeseries’ or ‘Go to Sub Sector timeseries’ icons.
- Please note that selections made in Steps 1 and 2 on the main page do not carry over to the time series charts. Users will select pollutant under ‘Step 1: Select a Pollutant’ and the year in ‘Step 2: Select Year’ to display the desired emissions trends. Hover over the vertical bars to view the annual emissions represented by that sector or subsector. Alternately, right-click within the chart and select ‘Show as a table’ to display the emissions time series in tabular format.
- Use the ‘back’ arrow or ‘Back to report’ button on the top-left corner of the screen to return to the main page. Select ‘Reset’ button to clear the current selection.
Caveats
Users should consider the following limitations and uncertainties when interpreting the data presented in this tool. A more detailed discussion of the limitations and improvements to this inventory is available in the online summary report, Bay Area Emissions Inventory Summary Report. The Air District plans to release an updated regional CAP emissions inventory with a new base year in 2027 and will incorporate more recent activity data, methodologies, and other improvements.
- The current regional CAP emissions inventory uses a base year that reflects emission reductions from regulations that have been adopted and were in effect at that time. Rules and regulations adopted prior to publication are incorporated into future year projections.
- Projected emissions beyond the base year rely on business-as-usual scenarios and are not adjusted to include impacts from recommended policies or local ordinances.
- The base year emissions estimates were developed using the latest activity data and methodologies, available at the time of publication.
Last Updated: 14/10/2026