Atmospheric Reactive Nitrogen Cycling over the Ocean

Nitrous acid (HONO) is a minor air pollutant, but plays a major role as a key precursor to the OH radical in the continental boundary layer.  OH in turn initiates most atmospheric chemical processes, removing primary pollutants and forming secondary species.

The ARNA project, led by Lucy Carpenter from the University of York, aims to understand the potential for photoenhanced reactions on aerosol particles to generate HONO from nitric acid, HNO3 - a mechanism which would reduce the atmospheric sink for nitrogen oxides.  Our contributions comprise laboratory studies of aerosol reactions forming HONO, and field measurements of nitrogen species at the Cape Verde Atmospheric Observatory in the tropical Atlantic Ocean (pictured).

This work is funded by the NERC, and is a collaboration with the Universities of York, Birmingham, Manchester and FAAM.