California Air Resources Board

CARB is responsible for developing a plan to detail how the State will achieve its GHG emissions reduction targets mandated by law.  CARB’s updated 2017 Scoping Plan reflects the new statewide GHG emissions reduction goals called for in SB 32 of 40 percent below 1990 emissions levels by 2030.  In the transportation sector, GHG emissions reducing measures include low carbon fuels, cleaner vehicles, and strategies to promote sustainable communities and improved transportation choices that result in curbing the growth in vehicle miles traveled (VMT).  Under SB 375, the development and implementation of SCSs, which link transportation, land use, housing, and climate policy at the regional level, are designed to reduce per capita GHG emissions.  This is partially accomplished through reductions in per capita VMT. 

In 2018, CARB adopted more aggressive SB 375 targets as one measure to support progress toward the 2017 Scoping Plan goals, which aim to get SCSs that plan to achieve, in aggregate, a 19 percent reduction in statewide per capita GHG emissions reductions relative to 2005 by 2035 from passenger vehicles.  However, additional state and local actions are needed to achieve the transportation system reductions necessary to meet our climate goals, which is approximately 25 percent reduction in statewide per capita GHG emissions by 2035 relative to 2005.

The 2017 Scoping Plan Update includes a discussion of the relationship between local government actions and achievement of the State’s long-term GHG emissions reduction goals, and non-binding recommendations to support local governments in their efforts to reduce GHG emissions.  The 2017 Scoping Plan Update also identifies that slower growth in VMT from more efficient land use development patterns would promote achievement of the State’s climate goals.

The following document includes technical information on what level of statewide VMT reduction would promote achievement of statewide GHG emissions reduction targets and the 2017 Scoping Plan goals.  The document describes the relationship between those GHG emissions reductions goals and the level of per capita VMT and GHG emissions reduction anticipated in existing SCSs.  The analysis in this document may serve multiple uses, including providing non-binding technical information that acts as an optional aide to local governments and lead agencies when evaluating an individual project’s transportation-related GHG impacts and whether they are consistent with statewide 2030 and 2050 GHG emissions reduction goals in response to Senate Bill 743 (Chapter 386, Stats 2013).

Supporting Calculations for 2017 Scoping Plan-Identified VMT Reductions