_:genid1 "Copyright protected. Obtain permission from the original figure source."^^ . "secondary-organic-aerosol-formation-mexico-city" . "Secondary Organic Aerosol (SOA) Formation in Mexico City "^^ . "Current state-of-the-art models under-predict the rapid formation of large amounts of SOA. Here, data are shown from Mexico City on 9 April 2003. Solid dots indicate observations and shaded areas indicate the predicted SOA- mass concentration attributed to classes of anthropogenic volatile organic compounds, such as aromatics (red), alkenes (green), and alkanes (black). Credit: R. Volkamer, University of California, San Diego; J.L. Jimenez, University of Colorado; F. San Martini, National Academy of Sciences; K. Dzepina, University of Colorado; Q. Zhang, SUNY Albany; D. Salcedo, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico; L.T. Molina, University of California, San Diego; D.R. Worsnop, Aerodyne Research; and M.J. Molina, University of California, San Diego (redrawn from Geophysical Research Letters with permission from the American Geophysical Union)."^^ . _:genid1 . . .