In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 20, No. 4 ( 2020-03-03), p. 2623-2635
Abstract:
Abstract. Aerosol iodine isotopes are pivotal links in atmospheric
circulation of iodine in both atmospheric and nuclear sciences, while their
sources, temporal change and transport mechanism are still not well
understood. This work presents the day-resolution temporal variation in
iodine-129 (129I) and iodine-127 (127I) concentrations in aerosols
from Xi'an, north-west China, during 2017/18. Both iodine isotopes have
significant fluctuations with time, showing the highest levels in winter,
approximately 2–3 times higher than in other seasons, but the
correlation between 129I and 127I concentrations reflects that they
have different sources. Aerosol 127I concentrations are found to be
noticeably positively correlated with air quality index and five air
pollutants. Enhanced fossil fuel combustion and inverse weather conditions
can explain the increased concentrations and peaks of 127I in winter.
The change in 129I concentrations confirms that the source and level of
129I in the monsoonal region were alternatively dominated by the
129I-enriched East Asian winter monsoon and the 129I-poor East
Asian summer monsoon. The mean 129I∕127I number ratio of
(92.7±124)×10-10 provides an atmospheric background
level for the purpose of nuclear environmental safety monitoring. This study suggests that locally discharged stable127I and
externally input 129I are likely involved in fine particles formation
in urban air, which provides insights into the long-range transport of air pollutants
and iodine's role in particulate formation in urban atmosphere.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-20-2623-2020
DOI:
10.5194/acp-20-2623-2020-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2020
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
