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Transportation's 7% Emissions Gap: Explained

By: Bill Higgins on Jul 01, 2020
Green shaded urban graphic with buildings and travel modes; with bold equation 25%-18%=7% (?).  Other words: scoping plan, GHG Targets, SB 375, RTP/SCS, SB 32, Appendix C

The purpose of this article is to explain that there is a seven percent gap between the emission reductions called for by the Air Resources Board (ARB) in its Scoping Plan and the actual reduction targets (also set by ARB) under SB 375. This gap matters because it means that additional state actions are needed to achieve the state’s climate goals. To date, most of the scrutiny about whether emissions targets in the “SB 375 category” (our phase) are being met have focused on the effectiveness of regional strategies. Fair enough. But very little discussion has been focused on what other strategies are being implemented to address the seven percent gap.  

We acknowledge we have a perspective here. Thus, we have relied on ARB documents to explain how and why this gap exists in order to remain as neutral as possible. 

What are the SB 375 Targets?

In 2018, ARB updated the SB 375 Regional Targets, which require the state’s 18 Metropolitan Planning Organizations (MPOs) to incorporate GHG reduction strategies within their Regional Transportation Plan (RTP). The framework to address the GHG reductions is called a Sustainable Communities Strategy (SCS). Each MPO received a target from ARB ranging from 13 to 19 percent “per capita,” meaning that the RTP must include a SCS that would reduce average emissions per person by the assigned percentage. As a result, all of the currently adopted SCSs would achieve, in aggregate, a nearly 18 percent reduction in statewide per capita on-road light-duty transportation-related GHG emissions (“SB 375 Category”).  [SeeScoping Plan-Identified VMT and State Climate Goals, page 3].

How Do the SB 375 Targets Fit Within the Scoping Plan? 

The Scoping Plan describes how the state can achieve the statewide GHG reduction goal set by SB 32 across all sectors. The statutory goal requires the state to achieve a 40 percent reduction in statewide emissions by 2030 (from the total emitted in 2020). In addition, the Scoping Plan also lays the groundwork for how the state can achieve the further objective achieving an 80 percent reduction by 2050. [SeeExecutive Orders S-03-05 (Schwarzenegger) and B-30-15 (Brown)].  

One important emission source is "the SB 375 category" for car and light truck travel. Here, the Scoping Plan seeks to reduce emissions by 25 percent. [See Scoping Plan, page 75.] This figure derives from an assumption that the state must realize a 15 percent reduction in vehicle miles traveled (VMT) by 2050 (based on the Executive Order goal) in yet another ARB plan called the Mobile Source Strategy. [See Mobile Source Strategy, page 36-37; and model details on page 166]. 

If you were reading closely you may have caught that these metrics do not align. SB 375 seeks to achieve per capita GHG emission reductions by the year 2035 using 2005 as a base year. Alternatively, the Scoping Plan/Mobile Source Strategy assumes that VMT will be reduced by the years 2030 and 2050, but uses 1990 as a base year. Making matters even more complicated, only the 40 percent by 2030 goal is in statute; the 80 percent reduction by 2050 figure is from an executive order.

After a lot of math, ARB reconciled the differing authorities, metrics, and target years. It calculated that a statewide “SB 375 category” target of 25 percent approximated a 7.5 percent reduction in VMT, which was the progress needed by 2035 to be on track for the 2050 VMT goal. [See Scoping Plan, page 75; see also:ARB SB 375 Workshop Presentation, slide 19]. 

Ergo, the Seven Percent Gap  

There is a seven percent gap between the 25 percent reduction (based on the 2050 VMT goal) in the Scoping Plan and the 18 percent per capita GHG reduction targets set under SB 375. ARB acknowledges that although the SB 375 targets "make significant progress,” they do not “provide all of the reductions that will be needed.” [See Scoping Plan, page 75].  As a result, additional per capita GHG emissions reductions are needed to meet the State’s climate goals. [See Scoping Plan-Identified VMT and State Climate Goals, page 4].

Why Weren’t the SB 375 Targets Set at 25 Percent?

The answer is that MPOs do not have all the authority they need to achieve the called-for reductions. ARB explored setting the SB 375 targets high enough to attain the state climate goals, but concluded that they could not be achieved given the current level of resources available to MPOs. [See Scoping Plan-Identified VMT and State Climate Goals, page 3]. For example, “other factors” like gas prices and employment, significantly affect personal travel behavior and SB 375 implementation. The constant change in such external factors require policymakers to “think through what tools and practices will allow each region to meet its goals.” [See SB 150 Report, page 24].

As a result:

"Structural changes and additional work by all levels of government are still needed to implement regional strategies. Staff and elected officials of local, regional, and state government have critical authorities and roles to contribute ... But as a whole, all actors responding rationally to the incentives, political forces, and policy restrictions in front of them have not been able to enact the magnitude of change needed ...The current structure of policies and lack of incentives will continue to produce and exacerbate the insufficient results unless shared responsibility, changes in authority or mandates and incentives, and strong, deliberate, collaborative action is taken to change them. CARB finds that this disconnect impedes progress on attaining the SB 375 targets and their co-benefits.” 

[See SB 150 Report, page 56].  

In other words, achieving the full reductions in the “SB 375 category” requires cooperation at all levels of government: local, regional and state:  

  • While no single agency or level of government alone bears the responsibility for this work; there is an important opportunity to partner across many agencies on taking collaborative action toward better results. [See SB 150 Report, page 4]. 

  • More discussion among a broad suite of stakeholders from transportation, the building community, financial institutions, housing advocates, environmental organizations, and community groups are needed to develop the needed set of strategies to achieve necessary VMT reductions. [See Scoping Plan, page 75].

  • California – at the state, regional, and local levels – has not yet gone far enough in making the systemic and structural changes to how we build and invest in communities that are needed to meet state climate goals. To meet the potential of SB 375 will require state, regional, and local agency staff and elected officials to make more significant changes across multiple systems that address the interconnected relationship of land use, housing, economic and workforce development, transportation investments, and travel choices. [See SB 150 Report, page 6].

Is There a Plan to Address the Seven Percent Gap? 

No.  Although Table 17 of the Scoping Plan provides a list of statewide strategies, ARB has yet to produce a comprehensive plan to assure that the state achieves reductions beyond the 18 percent assigned to regional agencies. One of the most recent actions that the state has taken from this table is to add the SB 743 VMT analysis into the CEQA Guidelines. This new rule will likely affect land use economics in a way that will yield GHG reductions. [See our SB 743 Resource Center]. But it would be aggressive to think it would cover all, or even most, of the seven percent gap.

Table 17 of the Scoping Plan also lists three additional strategies: 

  • Pricing.  Policies to support low-GHG transportation (e.g., road user, parking pricing, transit discounts)  

  • Performance Measures.  The state will harmonize performance with emission reductions and increase the competitiveness of transit and active transportation modes vial guideline documents, funding programs, and project selection.

  • ZEV Goals.  The operation of 1.5 million zero and hybrid light duty electric vehicles on California roads by 2025; and 4.2 million by 2030.  (Note: this goal would reduce GHG emissions, but not necessarily lead to VMT reductions; thus it’s an uneasy fit for this framework).

[See Scoping Plan, page 103]. Of these, ZEV policy and implementing pricing measures fall clearly outside the authority of MPOs. Harmonizing performance with emission reductions in state grant programs also falls within state authority, although many MPOs apply similar metrics to their selection criteria to increase competitiveness of different project types. 

And finally, there is Appendix C. The Scoping Plan states that “the gap between what SB 375 can provide and what is needed to meet the State’s 2030 and 2050 goals needs to be addressed through additional VMT reduction measures such as those mentioned in Appendix C.” [See Scoping Plan, page 79; emphasis added]. Appendix C lists about 30 high-level policy concepts that the state should “explore.” Many of these policies (like pricing and greater land use controls) will require a heavy political lift. The document is just nine pages and it lacks a fiscal analysis and discussion of how the policies should be prioritized. As a result, it is difficult to conclude that the policies in Appendix C are part of an integrated plan to achieve the Scoping Plan’s 25 percent reduction in emissions from light vehicle travel.   

What’s Our Point? 

Better understanding. We have engaged in many conversations when we raise the seven percent gap only to get confused looks. We are sympathetic: it's difficult to sort through all the ARB documents to draw a distinction between the reductions in the SB 375 targets and the Scoping Plan. There is also a lot of room for misinterpretation, which is why we relied so heavily on ARB’s documents. Our hope is that in distilling all this information in one place it will help build common ground among stakeholders. Hopefully it helped. 

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