A brief history of carbon emissions from the Northwest power system

The Pacific Northwest power system emits carbon but it is difficult to identify long-term trends or short-term events because of high year-to-year variation related to hydropower. However, it is possible to normalize CO2 emissions, essentially estimating what emissions would have been each year if runoff had been average. The method is relevant for identifying trends as well as setting CO2 emissions targets and verifying their achievement.1