Seasonal variation of gaseous HNO3 and NH3 at a tropical savannah site

Gaseous nitric acid and ammonia were sampled with annular denuders at a forest savannah site from April to December 1987. The analysis of the extract was made spectrophotometrically and by a selective electrode for NO3(-) and NH4(+), respectively. Higher concentrations were observed during the veget...

Full description

Saved in:
Bibliographic Details
Published in:Journal of atmospheric chemistry 1990-10, Vol.11 (3), p.245-254
Main Authors: RONDON, A, SANHUEZA, E
Format: Article
Language:English
Subjects:
Chemical composition and interactions. Ionic interactions and processes
Earth, ocean, space
Exact sciences and technology
External geophysics
Meteorology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Gaseous nitric acid and ammonia were sampled with annular denuders at a forest savannah site from April to December 1987. The analysis of the extract was made spectrophotometrically and by a selective electrode for NO3(-) and NH4(+), respectively. Higher concentrations were observed during the vegetation burning period at the end of the dry season. In the studied savannah area, large soil emissions of NO occur during the rainy season, although very low concentrations of HNO3 (0.035 ppb) and also of particulate NO3(-) (0.43 microg/cu m) were observed; it is likely that NO(x) are lost by fast vertical transport to the upper troposphere. During the nonburning period, the average concentration of NH3 was 2.7 ppb, which is much lower than values given in the literature for the tropical America atmosphere. The concentrations of HNO3 and NH3 were always below the values needed to produce ammonium nitrate aerosols. (Author)
ISSN:0167-7764
1573-0662
DOI:10.1007/BF00118351