SACRAMENTO - The Air Resources Board today released the California Greenhouse Gas Emissions Inventory for 2012. The annual inventory lists the total amount of greenhouse gases emitted from all sectors of California’s economy, compiled using regional, state and national databases.

The inventory revealed some notable trends. The state’s gross domestic product grew by 5 percent from 2009 to 2012 while the carbon intensity, the amount of carbon pollution related to the state’s overall economy, has fallen steadily over the same time period.

“The latest inventory clearly demonstrates that under AB 32 California is getting more economic development every year for each ton of greenhouse gases emitted overall,” said Air Resources Board Chairman Mary D. Nichols. “That’s good news for California and the message is clear: We need to stay the course we’re on to continue to grow California’s lower carbon economy.”  

After rising during the mid-2000s, the state’s greenhouse gas inventory fell in 2008 as a result of the recession. It has leveled off during the past four years while the economy recovered. The 2012 inventory of 459 million metric tons is about 2 percent higher than 2011 due to increased natural gas electricity generation in-state to compensate for the closure of the San Onofre Nuclear Generating Station and, because of a dry winter, to make up for the drop in hydro-powered generation.

The one-year rise in in-state generation also resulted in a 1 percent uptick to 12.1 tons per person. The long-term trend, however, is clear with a drop of 12 percent — almost 2 tons of GHG emissions per person — over the past decade. Although California ranks second in the nation in terms of total GHG emissions (after Texas) only five states (all in the northeast) have lower per capita GHG emissions.

California’s cap-and-trade program will ensure that emissions in future years will continually decline, even alongside stronger economic growth and potentially drier hydrological conditions, and in the event of any additional unforeseen circumstances. The declining cap also sets the state on a course to achieve the goal of AB 32 — reaching the 1990 level of greenhouse gases by 2020 and then maintaining it.  
Emissions from the transportation sector — still California’s largest single source of greenhouse gases, contributing 36 percent of total emissions — declined modestly compared to 2011, although it did so while the economy grew.

The long-term direction of transportation-related GHG emissions is another clear trend, with a 12 percent drop over the past seven years. Part of this decrease is due to larger numbers of new fuel-efficient vehicles on California roads. The hybrid vehicle market share increased in 2012 to 7.4 percent from the 2011 level of 5.4 percent, and the Toyota Prius — with a combined mpg of 50 — was the best-selling car in California in 2012.

The industrial sector emissions stayed relatively flat with some increases reflecting a recovering economy. Cement sector emissions grew 13 percent in 2012 as the state’s eight cement plants ramped up production.

This year’s inventory included six separate greenhouse gases (carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), sulfur hexafluoride (SF6), hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs)) and used the global warming potentials for each as outlined in the 4th Assessment Report of the Intergovernmental Panel on Climate Change.

Verified facility-specific emissions for 2013 filed under the Mandatory Greenhouse Gas Emissions Reporting program will be released this fall.

AB 32 requires overall reduction of greenhouse gases to the 1990 level by 2020. The primary AB 32 programs are cap-and-trade, the Low Carbon Fuel Standard, the Renewable Portfolio Standard and the Advanced Clean Cars program. Reductions also result from numerous energy efficiency and conservation programs.

To see the 2012 California Greenhouse Gas Inventory, click here. 

To see California’s AB 32 greenhouse gas reduction programs, click here.