Note: Gross greenhouse gas emissions (GHG) includes fossil fuel CO2, with electric imports and international fuels (carbon dioxide equivalents) and noncarbon GHG emissions (in CO2 equivalents). Noncarbon GHG emissions are made up of Agriculture (CH4 and N2O), Soils, ODS substitutes, Semi-conductor manufacture (PFCs), Electric Utilities (SF6). Cement, Other Industrial Processes, Solid Waste Management, Landfill Gas, and Wastewater, Methane from oil and gas systems, Methane and N2O from Fossil Fuel Combustion.
Data Source: California Air Resources Board, California Greenhouse Gas Inventory - by Economic Sector and Activity
Analysis by CEC Economics
Highlights
- After meeting the Assembly Bill 32 2020 target in 2016, total greenhouse gas emissions1 were 360.4 MMTCO2e in 2023, which is 17.6% (-77.0 MMTCO2e) below the 1990 levels of 437 MMTCO2e.2 Total GHG emissions decreased by 3.0% (-11.2 MMTCO2e) from 2022 to 2023. The year-over-year percentage decrease from 2022 to 2023 is greater than that from 2021 to 2022 (-2.4%). More importantly, GHG emissions in 2023 were also 2.4% lower than during the economic shutdown due to the COVID-19 pandemic in 2020, showing that California continues to reduce emissions even after the economy reopened and regular activity resumed.
- The largest decrease in GHG emissions from 2022 to 2023 came from the transportation sector, where emissions fell by 4.6% (-6.6 MMTCO2e), followed by the electric power sector, which fell by 4.2% (-2.5 MMTCO2e). Emissions from the industrial sector fell by 3.7% (-3.0 MMTCO2e) from 2022 to 2023. Within the electric power sector, emissions from imports decreased by 9.3% (-1.6 MMTCO2e) and emissions from in-state generation fell by 2.1% (-0.9 MMTCO2e). Emissions from the agriculture sector fell by 2.9% (-0.9 MMTCO2e) from 2022 to 2023.
1 The GHG inventory was developed in accordance with the Intergovernmental Panel on Climate Change (IPCC) Guidelines for National GHG Inventories, the internationally recognized standard for developing national GHG inventories. There exist other categories besides included emissions: excluded emissions, carbon dioxide from biogenic materials, emissions and removals from forest lands and wood products, and other emissions. Excluded emissions are discussed elsewhere in this chapter.
2 California Air Resources Board. AB 32 Global Warming Solutions Act of 2006. September 28, 2018. Accessed September 30, 2024. Available at: https://ww2.arb.ca.gov/resources/fact-sheets/ab-32-global-warming-solutions-act-2006
Challenges
- Emission reductions in commercial and residential buildings have been a mixed bag. Compared to 2022, GHG emissions in the commercial sector were 0.4 MMTCO2e lower (-1.5%), while they were 2.2 MMTCO2e higher (+6.8%) in the residential sector in 2023. These are also the only sectors where GHG emissions were higher in 2023 than in 2016 when California met the AB 32 goal of reducing GHG emissions to 1990 levels by 2020. The use of substitutes for ozone-depleting substances (SODs) in refrigeration and air conditioning activities single-handedly accounts for the commercial sector’s increase in emissions. The use of SODs also contributed to the increase in emissions from the residential sector, but this sector also saw an increase in emissions from heating fuel use (primarily natural gas) due to the colder winter in 2023 compared to 2022.
- California’s emissions are more than 98.0 MMTCO2e (or 37.3%) above the Senate Bill 32 target of 40% below 1990 level by 2030. When California achieved the AB 32 in 2016, to meet the SB 32 target by 2030, the state needed to decrease its emissions by 11.1 MMTCO2e per year.3 However, at the midway point, the state had managed to reduce emissions by 7.8 MMTCO2e per year between 2016 and 2023. This means to meet the SB 32 target by 2030, the state will need to double its current pace to reach 14.0 MMTCO2e per year from 2023 to 2030.
3 Legislative information on Senate Bill 32 (Pavley, 2016) can be found here: https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201520160SB32