Assessing the Influence of Climate Variability on Atmospheric Concentrations of Polychlorinated Biphenyls Using a Global-Scale Mass Balance Model (BETR-Global)
详细信息 查看全文
- 作者：Matthew MacLeod ; William J. Riley ; and Thomas E. Mckone
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：September 1, 2005
- 年：2005
- 卷：39
- 期：17
- 页码：6749 - 6756
- 全文大小：463K
- 年卷期：v.39,no.17(September 1, 2005)
- ISSN：1520-5851
文摘
We introduce a new global-scale multimedia contaminantfate model (the Berkeley-Trent Global Model; BETR-Global) that integrates global climate data from the NationalCenters for Environmental Prediction (NCEP). BETR-Global represents the global environment as a connectedset of 288 multimedia regions on a 15
grid. We evaluatethe model by simulating the global fate and transport ofseven PCB congeners over a 70 year period and findsatisfactory agreement between model output andobservations of atmospheric PCB concentrations at 11 long-term monitoring stations in the Northern Hemisphere.We demonstrate the use of the model as a tool forunderstanding global pollutant dynamics by examining thehypothesis that variability in global-scale climate conditions,as reflected by the North Atlantic Oscillation (NAO), influencesatmospheric PCB concentrations in the Northern Hemisphere. We estimate that the maximum variability inatmospheric PCB concentrations attributable to NAOvariability is approximately a factor of 2. The influence ofvariability in the NAO on PCB concentrations in air ismost likely to be observed in the winter and spring atmonitoring sites in Northern Europe and the Arctic. Analysisof long-term monitoring data from 11 sites shows somestatistically significant relationships between NAO indicesand atmospheric PCB concentrations during the winterand spring. Giving consideration to competing factors thatinfluence atmospheric PCB concentrations, longer timeseries of monitoring data are required to fully evaluate themodeling results and to improve our understanding ofthe role of climate variability on the long-term fate ofpersistent semivolatile pollutants.
grid. We evaluatethe model by simulating the global fate and transport ofseven PCB congeners over a 70 year period and findsatisfactory agreement between model output andobservations of atmospheric PCB concentrations at 11 long-term monitoring stations in the Northern Hemisphere.We demonstrate the use of the model as a tool forunderstanding global pollutant dynamics by examining thehypothesis that variability in global-scale climate conditions,as reflected by the North Atlantic Oscillation (NAO), influencesatmospheric PCB concentrations in the Northern Hemisphere. We estimate that the maximum variability inatmospheric PCB concentrations attributable to NAOvariability is approximately a factor of 2. The influence ofvariability in the NAO on PCB concentrations in air ismost likely to be observed in the winter and spring atmonitoring sites in Northern Europe and the Arctic. Analysisof long-term monitoring data from 11 sites shows somestatistically significant relationships between NAO indicesand atmospheric PCB concentrations during the winterand spring. Giving consideration to competing factors thatinfluence atmospheric PCB concentrations, longer timeseries of monitoring data are required to fully evaluate themodeling results and to improve our understanding ofthe role of climate variability on the long-term fate ofpersistent semivolatile pollutants.