It’s my fourth year as a TA for our ‘Experimental Atmospheric Chemistry’ undergraduate and graduate course at MIT, and today we have loaded up the department’s van with nitric oxide (NO) and ozone (O3) monitors, a uv radiometer, and three particulate monitors (PM 10, 2.5, and 1.0 um). As part of the ‘Pollution Exposure’ unit, we will synchronize the monitors and drive around Boston noting changes in pollutant levels and keeping notes to identify possible pollutant sources. The field trip is a good time, and this year our class has grown to ten students, which is the biggest class we’ve had since I helped develop the course in 2007 with my…