Progress Report: California on track to reach 2020 GHG target of 427 MMTCO2e

Another year has passed and California’s greenhouse gas emissions continue to fall. For purposes of this discussion, representative data covers years 2000 to 2015, inclusive.

Source: California Environmental Protection Agency Air Resources Board

“California’s GHG emissions have followed a declining trend since 2007,” the California Environmental Protection Agency Air Resources Board (ARB) emphasized in the Overview section of “California Greenhouse Gas Emissions for 2000 to 2015 – Trends of Emissions and Other Indicators,” an adjunct or supplement to its “2017 Edition California GHG Emission Inventory” document. “In 2015, emissions from routine emitting activities statewide were 1.5 million metric tons of CO2 equivalent (MMTCO2e) lower than 2014 levels, representing an overall decrease of 10% since peak levels in 2004. During the 2000 to 2015 period, per capita GHG emissions in California have continued to drop from a peak in 2001 of 14.0 tonnes per person to 11.3 tonnes per person in 2015, a 19% decrease. Overall trends in the inventory also demonstrate that the carbon intensity of California’s economy (the amount of carbon pollution per million dollars of gross domestic product (GDP)) is declining, representing a 33% decline since the 2001 peak, while the state’s GDP has grown 37% during this period.”

It’s all looking pretty promising.

2020 is only two years away. The state needs to lower GHGs to 427 million metric tons of carbon dioxide equivalent emissions by that time. In 2015, the state was at a level of 440.4 MMTCO2e. That means an additional 3.04 percent or about a 3 percent reduction.

However, there is one area that is troubling – transportation. Between 2013 and 2015, it appears that passenger vehicles are having the greatest influence on the rising transportation-sector-based emissions.

As reported by ARB, this time in the “New Report Shows California is Reducing Greenhouse Gas Emissions as Economy Continues to Grow,” Jun. 7, 2017 news release,” the agency observed: “Increased fuel consumption in 2015 resulted in a 3 percent increase in emissions from the transportation sector, which is the state’s largest source of greenhouse gases with 37 percent of statewide emissions.”

Referring again to the “Trends of Emissions and Other Indicators” document, the ARB adds: “Emissions from transportation sources were relatively constant through 2007, declined through 2013, then increased by 4.6 MMTCO2e (or 3%) from 2014 to 2015. On-road GHGs account for 99% of that increase. A combination of factors influences on-road transportation emissions. Regulations and improved fuel efficiency of the state’s vehicle fleet drive down emissions over time, but population growth, lower fuel prices, and improved economic conditions and higher employment rate are potential factors that may increase fuel use.

“Consistent with the IPCC Guidelines for National GHG Inventories and the annual GHG inventories submitted by the U.S. and other nations to the United Nations Framework Convention on Climate Change (UNFCCC), the biofuel components of fuel combustion CO2 emissions are classified as ‘biogenic CO2’ and are tracked separately as informational items from the rest of the emissions in the inventory (that are classified as ‘included’ emissions). The continuously increasing market penetration of biodiesel and renewable diesel was able to offset the increase in on-road heavy-duty diesel use. As a result, the on-road heavy-duty diesel category showed an overall decrease in ‘included’ emissions …. However, the percent of ethanol in gasoline blend dropped slightly in 2015 and did not offset the relative larger increase in gasoline fuel consumption ….”

Furthermore and as far as trend lines go, the electric power sector saw marked improvement while the industrial, agricultural, commercial and residential and recycling and waste sectors, all effectively remained unchanged. The high global warming potential (high GWP) gases category which accounts for 4 percent of all California GHG emissions, on the other hand, has seen steady growth from as far back as 2003.

“Emissions from the electricity sector continue to decline due to growing zero-GHG energy generation sources,” ARB in the “Trends of Emissions and Other Indicators” document continued. “Emissions from the remaining sectors have remained relatively constant, although emissions from high-GWP gases have continued to climb as they replace ozone depleting substances (ODS) banned under the Montreal Protocol.”

The prospect of California reaching its 427 million metric tons of carbon dioxide equivalent emissions 2020 GHG target which, incidentally, is what California emissions output in year 1990 was, looks pretty good.

That said, the goal beyond 2020 is to reduce said emissions an additional 40 percent a decade later and double that by mid-century.

2 thoughts on “Progress Report: California on track to reach 2020 GHG target of 427 MMTCO2e

  1. Thanks for your excellent summary here. I hope you will write a retrospective summary at the end of this year when Governor Brown’s term comes to an end re his impact (and his synergy with Art Rosenfeld) and the continuing impact of his appointees over his four terms as Governor.

    Data update.

    427 MMTCO2e was the old target for 2020 (i.e., returning to 1990 levels by 2020) before the IPCC came out with the new GWPs methodology from the IPCC Fourth Assessment. The new target number announced by the ARB is 431 MMTCO2e. Here are the sources.

    431 million metric tons CO2e by 2020. 2020 target set by AB 32 that California must achieve by the year 2020. “Global Warming Emissions. Then: 476.5 million tons CO2e* (2006, the year AB 32 was signed into law). Now: 441.5 million tons CO2e (2014). (Target: 431 million tons CO2e by 2020). Change: – 7.3%. * CO2e = carbon dioxide equivalent. Source: California Air Resources Board. California Greenhouse Gas Emission Inventory.” (UCS 2016, Adrienne Alvord, UCS director, California & Western States, “Ten Years After: Looking Back on California’s Global Warming Solutions Act (AB 32),”, Union of Concerned Scientists, Cambridge, Massachusetts, August 3, 2016)

    427 million metric tonnes of carbon dioxide equivalent (MMTCO2e). 2020/1990 level limited has been updated and increased from 427 MMTCO2e to 431 MMTCO2e by the ARB. “Original 2020 Limit. ARB staff constructed a 1990-2004 greenhouse gas emission inventory to determine the 1990 emission level and 2020 limit of 427 million metric tonnes of carbon dioxide equivalent (MMTCO2e), using IPCC second assessment report global warming potentials. The Board approved the 2020 limit on December 6, 2007. All materials related to board adoption of the original 2020 limit can be found in the 1990 archive page. Updates to the 2020 Limit. Calculation of the original 1990 limit approved in 2007 was revised using the scientifically updated IPCC 2007 fourth assessment report (AR4) global warming potentials, to 431 MMTCO2e. Thus the 2020 GHG emissions limit established in response to AB 32 is now slightly higher than the 427 MMTCO2e in the initial Scoping Plan. (ARB 2014, “California 1990 Greenhouse Gas Emissions Level and 2020 Limit,”, California Air Resources Board, Sacramento, California, May 13, 2014)

    It doesn’t materially change the conclusions or direction of anything in your excellent writeup. But it is slightly more accurate.

  2. I stand corrected.

    That said, many, many thanks for providing the added enlightenment. Much, much appreciated.

Leave a Comment