The flow visualization is created to illustrate the transport phenomena in the lower atmosphere, such as air stagnation, convergence of airmasses, fronts, ventilation, and general 3 dimensional motion. Three particles were released from each source every two hours, and were tracked for seven days. The calculation of the transport of the particles was done using the wind fields generated by the National Meteorological Center's Nested Grid Model with a grid resolution of 180 km. This movie displays several of the characteristics of regional scale flow in the lower atmosphere. During the day, the mixing height increases, and the particles are mixed throughout the layer diluting the high concentrations of particle that accumulated during the night.
Several instances are also apparent where two regional airmasses converge.
At the convergence zone, the flow is stagnant and there is a high density of particles. The converging airmasses cause upward vertical motion as seen by the large number of particles transported to heights above 4 km. The simulation also illustrates the ventilating effects of high wind speeds.