Oregon has pioneered a new and more comprehensive approach to assessing greenhouse gas emissions in order to better identify opportunities for, and track progress toward, reducing the state’s contribution to global greenhouse gas emissions. This new approach addresses gaps in traditional methods of state emissions accounting to help inform policy decisions. In 2007, Oregon’s Legislature adopted greenhouse gas reduction goals: to arrest growth and begin to reduce emissions by 2010, and to reach a 10 percent reduction below 1990 levels by 2020 and a 75 percent reduction from 1990 levels by 2050. To assess whether the state had met this first goal, Oregon agencies (Environmental Quality, Energy and Transportation) collaborated to prepare a comprehensive and multi-faceted inventory of emissions that expands upon traditional approaches to include worldwide emissions associated with Oregonians’ consumption, and a broad estimate of emissions associated with travel by Oregonians and freight serving Oregon’s economy.
Results to Date:
Key findings from Oregon’s greenhouse gas inventory report, Oregon’s Greenhouse Gas Emissions Through 2010: In-Boundary, Consumption-Based and Expanded Transportation Sector Inventories, include:
- Though emissions from the transportation sector remain the largest source of in-state emissions, the residential/commercial sector has become a nearly equal part of the traditional inventory.
- More than half of the emissions in the consumption-based inventory occur in other states and countries in order to make goods and services that Oregon imports for consumption.
- Freight and air travel are a growing part of Oregonians’ transportation emissions, as emissions from these travel segment have increased while emissions from passenger vehicles have recently begun to decline.
The recently published inventory of Oregon’s greenhouse gas emissions represents the next step in the evolution of greenhouse gas accounting in Oregon by including two important changes to inventories performed in previous years.
First, the accuracy of the traditional inventory of emissions within Oregon was improved by transitioning from an entirely “top down” modeling estimate to a primarily “bottom up” aggregation of data reported by the emission sources themselves. These reported emissions are derived from actual fuel volumes and electricity supplied in Oregon reported by the state’s fuel suppliers and electric utilities, and emissions calculated by the state’s largest industrial emitters.
Second, the report evaluates emissions through three different lenses: 1) the aforementioned inventory of emissions from in-state sources and electricity usage, 2) worldwide emissions associated with satisfying Oregonians’ consumption, and 3) an expanded examination of emissions from the transportation sector. To our knowledge, Oregon is the first state to include in its emissions inventory an estimate of global emissions resulting from local consumption, and to publish a greenhouse gas inventory report using more than one accounting approach. This innovation is important because no single inventory tells the full story of how Oregon contributes to global greenhouse gas emissions, and none is necessarily the “right” method for all contexts.
Ultimately, greenhouse gas inventories are intended to inform actions to reduce our contribution to greenhouse gas emissions. All three inventories help identify emission reduction opportunities for Oregon residents, businesses, government agencies, and policymakers. Multiple perspectives provide a more comprehensive understanding of how Oregon contributes to emissions, which gives us a broader range of ideas for how we can reduce these emissions.
Including out-of-state emissions alongside emissions from in-state sources has helped address criticism that state environmental policies may unfairly penalize in-state businesses by counting their emissions while ignoring the impacts of foreign competition. The greater breadth of sources and activities evaluated by the multiple inventories has been used to inform a variety of recent state climate planning, including the Oregon Global Warming Commission’s Interim Roadmap to 2020, the Governor’s 10 year Energy Action Plan, the Oregon Transportation Commission’s Statewide Transportation Strategy, and the Oregon Environmental Quality Commission’s Materials Management 2050 Vision and Framework for Action.
Air Quality Administrator
Oregon Department of Environmental Quality
(503) 229-5397 (office)
(503) 572-7195 (mobile)
 The report is available online here: http://www.oregon.gov/DEQ/AQ/Pages/Greenhouse-Gas-Inventory-Report.aspx