Atmospheric chemists have struggled for years to explain why our atmosphere has so much nitrous acid, a compound involved in the creation and removal of common air pollutants that impact human health. According to their computer simulations, there should only be about half as much nitrous acid as is actually measured in places like Beijing and Mexico City. Researchers at the University of Texas at Austin, the University of Nebraska-Lincoln and Beijing University of Chemical Technology have finally discovered why: microdroplets of water in clouds create a surface that allows the low-energy formation of nitrous acid from other common compounds in the atmosphere. It’s not clear if this additional mechanism for producing nitrous acid ultimately leads to more air pollutants or less, but it does indicate to atmospheric chemists that their models need to take into account more complex features of the natural environment. They publish their results today in the journal Proceedings of the National Academy of Sciences. The paper’s first author is postdoctoral researcher Lei Li (UT Austin and UNL). Senior authors are Graeme Henkelman (UT Austin), Joseph Francisco (UNL) and Xiao Cheng Zeng (UNL and BUCT).
