Diverging ozone trends above western North America: boundary layer decreases vs. free tropospheric increases

O.R. Cooper, G. Rodriguez, L.T. Iraci, E.L. Yates, M.S. Johnson, A. Gaudel, D.A. Jaffe, N. Bernays, H. Clark, P. Effertz, T. Leblanc, I. Petropavlovskikh, B. Sauvage, D.W. Tarasick