For more information about the data see this readme file and the peer-reviewed journal article:
Requia, W. J., Q. Di, R. Silvern, J. T. Kelly, P. Koutrakis, L. J. Mickley, M. P. Sulprizio, H. Amini, L. Shi, and J. Schwartz. 2020. An Ensemble Learning Approach for Estimating High Spatiotemporal Resolution of Ground-level Ozone in the Contiguous United States. Environmental Science & Technology, 54(18):11037-11047. https://doi.org/10.1021/acs.est.0c01791.
The above article has open access Supplementary Information at https://pubs.acs.org/doi/suppl/10.1021/acs.est.0c01791/suppl_file/es0c01791_si_001.pdf.