The Relative Roles of RONO2 and HNO3 as Sinks of NOX in the Denver Metropolitan Region and Colorado’s Front Range

Abstract:

Measurements of HNO₃, total RONO₂, NO_X, and other relevant species, acquired during the DISCOVER-AQ and FRAPPE field campaigns in the Northern Front Range of Colorado during July-August 2014, are used to assess our understanding of the relative roles of RONO₂ and HNO₃ formation as sinks of NO_X. Although HNO₃ production was dominant in the region, RONO₂ production was often of order 1/3 of the NO_X sink. As NO_X emissions decrease, our results indicate RONO_2­ chemistry will be increasingly important to descriptions of the chemistry in the region.