Nitrogen dioxide reductions from satellite and surface observations during COVID-19 mitigation in Rome (Italy).

Lockdown restrictions were implemented in Italy from 10 March 2020 to contain the COVID-19 pandemic. Our study aims to evaluate air pollution changes, with focus on nitrogen dioxide (NO), before and during the lockdown in Rome and in the surroundings. Significant NO declines were observed during the COVID-19 pandemic with reductions of - 50%, - 34%, and - 20% at urban traffic, urban background, and rural background stations, respectively.

Emission of submicron aerosol particles in cement kilns: Total concentration and size distribution.

Cement plants are responsible for particle and gaseous emissions into the atmosphere. With respect to particle emission, the greater part of is in the range from 0.05 to 5.

Study of nitrogen containing compounds in the polar troposphere.

Atmospheric nitrogen compounds play a critical role in tropospheric photochemistry and are crucial to understand the chemical and physical evolution of atmospheric pollutants in polar areas. Measurements of these species in remote areas are rare, although their relevance is well established. Sampling campaigns of gaseous and particulate atmospheric trace species were performed in Arctic and in Antarctica during three consecutive years (1997-1999), using a proper combination of annular denuders and filter pack.