Airmass Histories for Pollution Events (IMAGE) Michigan Technological University Caption Model simulations that indicate the airmass histories for three pollution events: PMO-1 (June 28, 2013), PMO-2 (July 6, 2014) and PMO-3 (June 21, 2015). The model simulations show the column integrated residence times over a 20-day transport time and their vertical distributions at given upwind times. The labels indicate the approximate locations of the center of the plume for each of the transport days. Further description can be found in Schum et al. Atmospheric Chemistry and Physics, 2018. Credit Schum et al.<i>Atmospheric Chemistry and Physics</i>, 2018 Usage Restrictions Please be sure to credit photo. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.