Seasonal variation of gaseous HNO3 and NH3 at a Tropical Savannah site |
| |
| Authors: | Alberto Rondón Eugenio Sanhueza |
| |
| Institution: | (1) Instituto Venezolano de Investigaciones Científicas, IVIC, Apartado 21827, 1020-A Caracas, Venezuela;(2) Present address: Department of Meteorology, University of Stockholm, 10691 Stockholm, Sweden |
| |
| Abstract: | 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  g m-3) were observed; it is likely that NOx 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. |
| |
| Keywords: | Nitric acid ammonia tropical atmosphere vegetation burning |
| 本文献已被 SpringerLink 等数据库收录！ |
|
