State and Local Climate and Energy Program From Inventory to Action: Putting Greenhouse Gas Inventories to Work What are the uses of inventory results? Developing an inventory is typically the first step toward setting a state or local emissions goal, but inventory results have a variety of other important uses. In some ways, having an inventory is like having a GPS unit in your car: it shows you where you are, how to get to where you want to go, and how far along the path you've progressed. States and localities use greenhouse gas inventories to do the following: • Identify sources of emissions, their current magnitude, and their rate of growth. An inventory can reveal which sources require priority attention and which are too small to effectively matter. • Establish a foundation for projecting future emissions. • Provide a basis for emissions goals and a benchmark for progress toward achieving them. • Evaluate the effects of proposed emissions reduction policy options. Note that emissions inventories involve a process of continuous improvement: as methodologies are refined and more reliable or comprehensive sources of data are developed, states and localities can improve the accuracy of their inventories and projections. Key steps and issues in setting emissions goals Some of the choices and decisions below will be determined in part by inventory results; in all cases the results of inventories (and projections based on them) will factor into the decision-making process. • Scope: States and localities need to decide whether they will set goals for all six basic greenhouse gases or a subset of them (such as carbon dioxide, methane, and nitrous oxide). Goals may be set for the entire economy of a jurisdiction, a subset of the economy, or particular sectors. • Time frame: Emissions goals may be short-term (e.g., two to five years out), mid-term (e.g., 20-30 years), or long-term (e.g., 40-50 years). The goals' time frame will influence the range of actions and policy options used to achieve them. A state or locality may set a long-term goal but also have short- term targets that serve as incremental steps toward that goal. This approach may allow you to test and demonstrate the viability of a range of policy options for reducing emissions while working toward longer- term goals. ------- 1 fill N Vi California GHG Inventory Forecast Last updated: June 26, 2008 600 500 S 400 300 = 200 100 1990 Base year: The choice of a base year from which to compare emission reduction goals is very important, although this may be limited by data availability. Ideally the base year should be "typical," in the sense that emissions during that year were not influenced by unusual conditions such as extremely high or low economic growth, abnormal weather, or other outliers. Criteria: States and localities have a range of criteria to choose from in setting their emissions goals. A goal may be based on a scientific recommendation, such as aiming to reduce emissions by 80 percent below 1990 levels by 2050 in order to stabilize atmospheric concentrations at levels that avoid dangerous impacts. Alternatively, goals and baseline years may be established to be consistent with existing targets, such as those of the U.S. Council of Mayors' Climate Protection Agreement or another established international, national, or regional agreement. Goals also may be designed to be pragmatic, based on technical and economic feasibility; this is often the case for short-term goals. EPA, state governments, and a variety of organizations can provide support for efforts to set emissions goals and develop policies to achieve them. For more information, please visit the following EPA resources online: Climate Change: State and Local Governments http://www.epa.gov/climatechange/wycd/stateandlocalgov/index.html Climate Change: State and Local Tools and Resources http://www.epa.gov/climatechange/wycd/stateandlocalgov/tools resources.html Clean Energy: Local Best Practices http://www.epa.gov/cleanenergv/energy-programs/state-and-local/local-best-practices.html Clean Energy: State Best Practices http://www.epa.gov/cleanenergv/energy-programs/state-and-local/state-best-practices.html Clean Energy: State and Local Tools and Resources http://www.epa.gov/cleanenergv/energy-programs/state-and-local/tools.html 2002-2004 average 2020 Transportation Electric Power Commercial and Residential Industrial Recycling and Waste High GWP Agriculture Forestry California projected business-as-usual emissions (see graph) from its inventory to assess what reductions would be needed to meet 1990 emissions levels by 2020. Source: Draft California 2020 Greenhouse Gas Emissions Forecast, 2008. EPA-430-F-09-002 February 2009 ------- |