Appropriate for Grades 9-12 Students will use 2 PASPORT temperature sensors to investigate how a temperature inversion traps smog and reduces the overall visibility in a model of a smog-infested city. This activity can be completed in 2 50-minute lab sessions. Includes instructions. Requires 2 sensors and 2 USB Links or 2 Xplorer Dataloggers for each group of students. If your computer does not have 2 USB ports, then you will need a USB 4-Port Hub.