POREC Dataset

Process-Based On-Road Emissions for California (POREC): Data will be released soon.

On-road vehicle emissions significantly impact urban air quality and human health. While exhaust emissions decrease due to electrification and regulations, brake and tire wear (BTW) emissions are becoming a primary source of traffic-related pollution. However, most gridded inventories fail to isolate BTW processes.

To bridge this gap, we developed POREC (Process-Based On-Road Emissions for California), a high-resolution ($1\text{ km} \times 1\text{ km}$, hourly) gridded dataset. Created by coupling EMFAC and ESTA models, POREC maps eight distinct emission processes—spanning exhaust, evaporative, and non-exhaust (brake and tire wear) sources—using seven spatial surrogate categories and detailed chemical speciation. Validated against FIVE, POREC provides the first 1 km process-based mapping of vehicle emissions in California to advance fine-scale air quality modeling and health impact assessments.