2025 Mobile Source Strategy

The State of California has many air quality, climate, and community risk reduction goals to achieve over the next twenty-five years. CARB staff has been developing the 2025 Mobile Source Strategy with a plan to build on the integrated planning approach used in development of the 2016 and 2020 Mobile Source Strategies to identify the level of transition to cleaner mobile source technologies needed to achieve all of California’s air quality and climate targets. Mobile sources and the fossil fuels that power them continue to contribute a majority of emissions of diesel particulate matter as well as smog- and particulate‑forming pollutants such as oxides of nitrogen (NO_x), and the largest portion of greenhouse gas emissions in California.

In recognition of the value of the 2016 Mobile Source Strategy in relation to the State’s ongoing air quality, climate, and community risk reduction challenges, and the ever-evolving vehicle market, the California Legislature passed Senate Bill (SB) 44, signed by Governor Newsom into law on September 20, 2019. SB 44 acknowledges the ongoing need to evaluate opportunities for mobile source emissions reductions and requires CARB to update the 2016 Strategy by 2021, and every 5 years thereafter.

Update - March 2025

CARB is pausing development of the Mobile Source Strategy and reconsidering the approach. In light of the recent staffing cuts, and because there are several areas of work on transportation already happening, we are exploring approaches to avoid duplicative work.