IDENTIFICATION OF THE ORIGINS OF ELEVATED ATMOSPHERIC MERCURY EPISODES USING A LAGRANGIAN MODELLING SYSTEM
Item
Title (Dublin Core)
eng
IDENTIFICATION OF THE ORIGINS OF ELEVATED ATMOSPHERIC MERCURY EPISODES USING A LAGRANGIAN MODELLING SYSTEM
Description (Dublin Core)
eng
We report the application of a receptor-oriented transport model, the Stochastic Time-Inverted Lagrangian Transport
(STILT) model, to the interpretation of hourly total gaseous mercury (TGM) concentrations at three monitoring sites in Southern
Ontario during four episodes of high TGM. STILT is a Lagrangian modelling system (Lin, J.C. et al. 2003) that simulates the
transport of ensembles of air parcels backward in time from an observation point to upstream locations where surface inputs of
target species occurred. A complete inventory of anthropogenic and natural mercury sources were used to compute the emissions.
The study was initiated by simulating the mercury concentrations in a North American domain using CMAQ-Hg, a regional
Eulerian chemical transport model (CTM). The STILT model was applied to several short episodes (usually lasting for 1-4 days) in
which the TGM measurements at four air quality measurement stations in Southern Ontario significantly exceeded the predictions of
the CTM. The STILT analysis compared the origins of air parcels arriving during the elevated TGM episodes with those of air
parcels arriving at proximal times when the measurements and the CTM predictions were both low.
The results consist of the STILT–predicted hourly concentrations at the measurement site as well as the surface footprint where the
mercury responsible for the episode was emitted. The temporal STILT prediction is in better agreement with the measured time
series than that of CMAQ-Hg. We believe this is partly due to the superior ability of STILT to capture near-field influences and
partly due to the spatial averaging inherent in Eulerian modelling. Also, the predicted footprint locations were reasonable,
coinciding with known locations of large mercury sources during the high episodes and with cleaner areas otherwise.
(STILT) model, to the interpretation of hourly total gaseous mercury (TGM) concentrations at three monitoring sites in Southern
Ontario during four episodes of high TGM. STILT is a Lagrangian modelling system (Lin, J.C. et al. 2003) that simulates the
transport of ensembles of air parcels backward in time from an observation point to upstream locations where surface inputs of
target species occurred. A complete inventory of anthropogenic and natural mercury sources were used to compute the emissions.
The study was initiated by simulating the mercury concentrations in a North American domain using CMAQ-Hg, a regional
Eulerian chemical transport model (CTM). The STILT model was applied to several short episodes (usually lasting for 1-4 days) in
which the TGM measurements at four air quality measurement stations in Southern Ontario significantly exceeded the predictions of
the CTM. The STILT analysis compared the origins of air parcels arriving during the elevated TGM episodes with those of air
parcels arriving at proximal times when the measurements and the CTM predictions were both low.
The results consist of the STILT–predicted hourly concentrations at the measurement site as well as the surface footprint where the
mercury responsible for the episode was emitted. The temporal STILT prediction is in better agreement with the measured time
series than that of CMAQ-Hg. We believe this is partly due to the superior ability of STILT to capture near-field influences and
partly due to the spatial averaging inherent in Eulerian modelling. Also, the predicted footprint locations were reasonable,
coinciding with known locations of large mercury sources during the high episodes and with cleaner areas otherwise.
Creator (Dublin Core)
Wen, Deyong
Lin, John C.
Meng, Fan
Sloan, James J.
Publisher (Dublin Core)
Croatian meteorological society
Date (Dublin Core)
2008
Type (Dublin Core)
text
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://hrcak.srce.hr/64254
eng
https://hrcak.srce.hr/file/96371
Source (Dublin Core)
Hrvatski meteorološki časopis
ISSN 1330-0083 (Print)
ISSN 1849-0700 (Online)
Volume 43
Issue 43/1
Language (Dublin Core)
eng
Rights (Dublin Core)
info:eu-repo/semantics/openAccess
The papers of this Journal are free of charge for personal or educational use, with respect of copyright of authors and publisher.