Vertical Structure And Surface Interactions Of Nitrous Acid Using A 1D Model

Abstract

This study was undertaken in order to study the vertical distribution and surface interactions of gas-phase HONO under non-ideal mixing conditions during the 2011 NACHTT campaign using the Platform for Atmospheric Chemistry and vertical Transport in One Dimension (PACT-1D) model. This work builds on a previous 0D modelling study from the NACHTT campaign, where the greatest unknown source rate of HONO was found during the early morning when a morning burst of HONO were observed and a stable nocturnal boundary layer formed. The 48-hour model was initialized using observational constraints selected during periods where a morning burst of HONO were observed and a stable nocturnal boundary formed. The modelled HONO showed excellent agreement with observations when heterogeneous ground surface processes of HONO, surface water, and vertical mixing were accounted for without the need to apply additional daytime sources of HONO.