The Office of Sustainability & Environment tracks and measures Seattle’s greenhouse gas emissions on a regular basis. Called greenhouse gas inventories, these reports identify the source and amount of greenhouse gas production across the city of Seattle. These inventories are critical tools that inform our planning and monitor progress made toward our climate protection goals.
Seattle measures “core” greenhouse gas emissions in our inventories. Core emissions are those that the City can most directly affect – Transportation, Building Energy and Waste. Seattle’s latest greenhouse gas inventory shows total emissions decreased in building energy and waste but they increased in road transportation.
Emissions from road transportation increased 9% since 1990, or 193,000 metric tons CO2, primarily due to Seattle’s increasing population and economic activity and the associated increase in overall vehicle travel. The good news is that vehicle emissions per person declined by 11%, as residents drive cleaner cars fewer miles. In fact, Seattle’s per person core emissions have been about half the national average and a third lower than the average King County resident outside Seattle.
It is important to remember that between 1990 and 2012, Seattle’s population and jobs grew 23% and 14% respectively, even while our overall emissions fell. The 2012 GHG inventory demonstrates that cities can grow in population and economic activity while still reducing emissions.