The Challenge
Transportation agencies and air quality professionals need reliable tools to evaluate how roadway emissions affect pollutant concentrations in nearby communities. CALINE4, the California Line Source Model version 4, has been used around the world for near-road air pollution modeling, but evolving assessment requirements and computing environments created a need for a more accessible and versatile version of the model.
Users needed a tool that could simplify near-road modeling while expanding assessments beyond carbon monoxide to address additional pollutants of concern, including particulate matter and nitrogen dioxide.
Our Solution
Spheros Environmental, together with researchers at the University of California, Davis, developed CL4, a user-friendly version of CALINE4 designed to streamline near-road pollutant modeling.
Building on the original CALINE4 model, which was developed for the California Department of Transportation (Caltrans), the team updated CL4 to make it easier for users to conduct particulate matter and nitrogen dioxide assessments in addition to the carbon monoxide analyses supported by the original model.
Spheros software developers incorporated onscreen programming tips to simplify the modeling process, improved compatibility across a wide range of desktop and laptop computing environments, and created an easy-to-use interface that enables users to rapidly assess multiple pollutant scenarios.
Air Quality Modeling and Software Development Consultant
Results +What makes this unique
CL4 makes established near-road air quality modeling capabilities more accessible and efficient for transportation and air quality professionals. The updated tool expands the types of pollutants users can readily assess while providing a more intuitive interface and greater compatibility with modern computing environments.
The project is distinguished by Spheros’ long-standing connection to the underlying science. The original CALINE4 model was developed by a Sonoma Technology scientist during his career with Caltrans, and the subsequent development of CL4 combined that deep technical knowledge with contemporary software expertise.
By integrating air quality science, transportation emissions modeling, and user-focused software development, CL4 provides a practical tool for evaluating near-road pollutant concentrations and supporting transportation-related air quality assessments.
A review of the development and application of the CALINE3 and 4 models
Project Experts
