Daytime and nighttime removal processes of atmospheric NO2 and NH3 in Araraquara's region – SP

Abstract

Nitrogen oxides and ammonia are important nitrogen compounds which are emitted to the atmosphere. They are very important substances in the environment. In the atmosphere, these substances may undergo diverse reactions that result in changes of chemical and physical atmosphere's property. Atmospheric removal mechanisms of nitrogen substances may ocurr either dry deposition or wet deposition. Human activity such as food production, energy and fertilizer have increased the nitrogen emissons to environment, causing disturbances in the natural nitrogen cicle. Parallel determinations of ammonia (NH3) and nitrogen dioxide (NO2) were made to assess variations of concentration and to infer about removal processes theses nitrogen compounds of Araraquara's atmosphere. Results showed the narrow relationship between these substances in the studied atmosphere. This relationship between ammonia and nitrogen dioxide suggested different removal processes at different periods during the year.