Náttúrufræðingurinn - 1989, Blaðsíða 37

SUMMARY
Determinations of ozone and
nitrogen oxides (NOx) in ambient
air in the vicinity of Reykjavík
during the summers 1982-1987.
by
Torkell Jóhannesson
Commission on Toxic Substances,
P.O. Box 109
IS-121 REYKJAVÍK,
Iceland
and
Hördur Thormar
The Technological Institute of Iceland.
Keldnaholt,
IS-112 REYKJAVÍK,
Iceland.
Ozone (03) was determined in ambient air
(altogether 33 samples) on sunny and rela-
tively hot summer days (approximately 10-
17°C) at a site several kilometers from the
nearest urban dwellings (approximately 17
km to the south of the center of Reykja-
vík) and at the base of a mountain ridge
almost 200 m above sea level (Fig. 1). The
amounts of ozone in ambient air were al-
ways low (1.1-10‘2 - 2.4-10'2pl/l; Table 1
and Fig. 2, or in the same or a similar
range as have been previosly found in arc-
tic and antarctic regions or in the Alps.
The amounts of nitrogen oxides (NOx)
were determined simultaneously in order
to evaluate whether there was any scav-
enging effect due to their presence on the
levels of ozone in the air. NOx were al-
ways present in very low amounts (2.8T0'3
- 5.010'3 fd/1; Table 2) or lower than pre-
viously found by us in ambient air in open
areas in the city of Reykjavík. It was con-
cluded that the amounts of ozone were
similar to those that could be expected
from natural causes only and most likely
excluded any possibility of occurrence of
photochemical smog in the region. The
necessity of continual monitoring of ozone
levels in ambient air in the vicinity of
Reykjavík was, however, emphasized.
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