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Oxides of nitrogen at two sites in New Zealand
Author(s) -
Stedman D. H.,
McEwan M. J.
Publication year - 1983
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl010i002p00168
Subject(s) - noon , ozone , atmospheric sciences , diurnal temperature variation , environmental science , nitrogen , nitrogen oxide , precipitation , nitrogen oxides , air pollution , climatology , environmental chemistry , meteorology , nox , chemistry , geology , geography , organic chemistry , waste management , engineering , combustion
Oxides of nitrogen, ozone and solar UV radiation were measured at two New Zealand sites, four months at Mt. John near Lake Tekapo, and one month at the New Zealand Department of scientific and Industrial Research, Physics and Engineering Laboratory Atmospheric Station (PELAS) near Lauder. The former site proved ideal for clean‐air measurements. Ozone concentrations of ∼20‐25 ppb, with little diurnal variation were accompanied by total nitrogen oxide (NO y ) levels frequently less than 150 ppt (parts in 10 12 by volume). The noon NO and NO 2 data were well correlated with a slope comparable to model values. Gaseous HNO 3 was observed to be significantly above the noise level (∼15 ppt) for only twenty‐seven four‐hour averages. For these a median of 43 ppt was obtained with a median ([NO y ]‐[HNO 3 ])/[HNO 3 ] ratio of 7.5, not comparable with model values of around 1.1. This low HNO 3 may arise from the fact that the Mt. John site is downwind of a mountain range which experiences significant upwind precipitation. At the PELAS site, strong diurnal variation of ozone and much larger NO y concentrations were observed. The difference is apparently caused by local sources of nitrogen oxides and the local meteorology at the fertile valley PELAS site.