Integrating a Comprehensive Modal Emissions Model into ATMIS Transportation Modeling Frameworks

Intelligent Transportation Systems (ITS) have generated considerable enthusiasm in the transportation community as a potential means to improve roadway safety, reduce congestion, enhance the mobility of people and goods, and reduce energy consumption and vehicle emissions. In order to estimate these potential benefits, new and improved analytical techniques and simulation models are being developed for ITS. In terms of environmental effects, the University of California, Riverside, College of Engineering-Center for Environmental Research and Technology (CE-CERT) has developed a comprehensive modal emissions and energy consumption (CME/EC) model that can be directly used for ITS evaluation. In this project, an examination was performed on the key interface issues between the detailed CME/EC model and other ITS simulation models and analytical techniques developed within the California PATH program. Methodologies for integrating various ITS transportation models/data sets with the CME/EC model were established. These integration issues are not trivial; many ITS simulation models and analytical techniques inherently have different levels of aggregation and detail (e.g., both in time and across various vehicle fleets). Much of the work performed focused on integrating the CME/EC model with PARAMICS. PARAMICS is used throughout CALTRANS and the PATH program for various ITS studies. After successfully completing this integration, two case studies were carried out using this PARAMICS/CME-EC tool. The first case study examined the emissions impact of HOT lanes along the SR-91 corridor in Southern California. The other case study examined the emissions impact associated redesignating uphill lanes on I-60 near Riverside, California. By completing these case studies, the integrated transportation/emissions model was thoroughly debugged. These case studies can serve as examples as how to apply this new tool for creating microscale emission inventories. In this report, background material is first provided on the Comprehensive Modal Emissions/Energy Consumption (CME/EC) model and ITS traffic simulation modeling efforts in the California PATH program. This is followed by a description of the integration methodology between CME/EC and PARAMICS. In the last part of the report, two separate case studies are described, where analyses with the integrated models were carried out.