『Abstract
The major objective of this paper is to provide insights to sources
and sinks of nitrous acid in urban areas, and their seasonal dependency
on meteorology, photochemistry and long range transport. With
this aim, nitrous acid (HONO) mixing ratios and other compounds
were measured in Ashdod (south of Tel Aviv, Israel), a typical
Mediterranean urban area. Statistical data analysis revealed the
expected correlation between HONO sources appeared to be traffic-,
harbor-, and industry-related. Conversely, during summer HONO
and NO2 were no longer correlated: NO2 at nighttime was probably deposited onto surfaces,
soil and plants, whereas HONO at daytime was likely destroyed
photolytically contributing to the OH concentration. Photolysis
was expected to be the dominant HONO sink at daytime, especially
during the summer period. Using modeled photolytical HONO lifetimes
we estimate the magnitude of heterogeneous and/or organic electron
transfer source reactions of HONO as 6-8 ppbv/h.
Keywords: HONO; Urban pollution; Atmospheric chemistry; Air pollution;
Israel』
1. Introduction
2. Experiment
3. Results and discussions
3.1. Autumn campaign
3.1.1. Factor analysis of fall campaign
3.2. Summer campaign
3.2.1. Factor analysis for summer campaign
4. conclusions
Acknowledgements
References