Dominance of Plastic Emission in the High Arctic Aerosol in Light Spring.

Arctic haze has attracted considerable scientific interest for decades. However, limited studies have focused on the molecular composition of atmospheric particulate matter that contributes to Arctic haze. Our study collected atmospheric particles at Alert in the Canadian high Arctic from mid-February to early May 2000.

Tracing the origin and fate of NOx in the Arctic atmosphere using stable isotopes in nitrate.

Atmospheric nitrogen oxides (NOx =NO+ NO2) play a pivotal role in the cycling of reactive nitrogen (ultimately deposited as nitrate) and the oxidative capacity of the atmosphere. Combined measurements of nitrogen and oxygen stable isotope ratios of nitrate collected in the Arctic atmosphere were used to infer the origin and fate of NOx and nitrate on a seasonal basis. In spring, photochemically driven emissions of reactive nitrogen from the snowpack into the atmosphere make local oxidation of NOx by bromine oxide the major contributor to the nitrate budget.