|
Titel |
Characterising terrestrial influences on Antarctic air masses using Radon-222 measurements at King George Island |
VerfasserIn |
S. D. Chambers, S.-B. Hong, A. G. Williams, J. Crawford, A. D. Griffiths, S.-J. Park |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7316
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 14, no. 18 ; Nr. 14, no. 18 (2014-09-18), S.9903-9916 |
Datensatznummer |
250119047
|
Publikation (Nr.) |
copernicus.org/acp-14-9903-2014.pdf |
|
|
|
Zusammenfassung |
We report on one year of high-precision direct hourly radon observations at
King Sejong Station (King George Island) beginning in February 2013. Findings
are compared with historic and ongoing radon measurements from other
Antarctic sites. Monthly median concentrations reduced from 72 mBq m−3
in late-summer to 44 mBq m−3 in late winter and early spring. Monthly
10th percentiles, ranging from 29 to 49 mBq m−3, were typical of
oceanic baseline values. Diurnal cycles were rarely evident and local
influences were minor, consistent with regional radon flux estimates one
tenth of the global average for ice-free land. The predominant fetch region
for terrestrially influenced air masses was South America
(47–53° S), with minor influences also attributed to aged
Australian air masses and local sources. Plume dilution factors of 2.8–4.0
were estimated for the most terrestrially influenced (South American) air
masses, and a seasonal cycle in terrestrial influence on tropospheric air
descending at the pole was identified and characterised. |
|
|
Teil von |
|
|
|
|
|
|