Concentration and size distribution of particulate oxalate in marine and coastal atmospheres – Implication for the increased importance of oxalate in nanometer atmospheric particles

In literature, particulate oxalate has been widely studied in the total suspended particles (TSP), particles 100 nm. In this article, we measured oxalate's concentrations in size-segregated atmospheric particles down to 10 nm or 56 nm during eight campaigns performed at a semi-urban coastal site, over the marginal seas of China and from the marginal seas to the northwest Pacific Ocean (NWPO) in 2012–2015. When the sum of the oxalate's concentration in particles 100 nm.•Oxalate in 0.01–0.056 μm particles were increased on the NPF-event days.•The mass ratio of oxalate to sulfate were greatly increased in particles