This article describes the use of ground-based, upper air, and satellite-based measurement platforms for characterizing the vertical structure of the atmosphere and how information from these platforms can play a critical role in the Air Quality Model Evaluation International Initiative (AQMEII) model evaluation exercises. Profile and Remote Sensing Observation Datasets North American and While the vast majority of operational air pollution networks across the world are designed to measure relevant metrics at the surface, the air pollution problem is a three-dimensional phenomenon. The lack of adequate observations aloft to routinely characterize the nature of air pollution throughout the air column continues to limit our understanding of pollutant transport. This is especially true in the characterization of nocturnal residual layers and the downward mixing of these layers the following day at locations far removed from the source region as the planetary boundary layer (PBL) grows during the daytime heating. Within the AQMEII, 1,2 one of the main goals is to work across continents to develop a sustained capability to evaluate regional-scale air quality models to simulate pollutant transport and transformation processes throughout the PBL and free tropo-sphere (FT) and identify and improve model deficiencies. An underlying objective is to promote the need for high-quality observations to adequately characterize atmospheric processes and changes