scholarly journals Modelling atmospheric transport of persistent organic pollutants in the Northern Hemisphere with a 3-D dynamical model: DEHM-POP

2004 ◽  
Vol 4 (2) ◽  
pp. 1339-1370
Author(s):  
K. M. Hansen ◽  
J. H. Christensen ◽  
J. Brandt ◽  
L. M. Frohn ◽  
C. Geels
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Model Simulation ◽  
Model Development ◽  
Average Concentration ◽  
The Arctic ◽  
Atmospheric Concentration ◽  
Surface Exchange

Abstract. The Danish Eulerian Hemispheric Model (DEHM) is a 3-D dynamical atmospheric transport model originally developed to describe the atmospheric transport of sulphur into the Arctic. A new version of the model, DEHM-POP, developed to study the atmospheric transport and environmental fate of persistent organic pollutants (POPs) is presented. During environmental cycling, POPs can be deposited and re-emitted several times before reaching a final destination. A description of the exchange processes between the land/ocean surfaces and the atmosphere is included in the model to account for this multi-hop transport. The α-isomer of the pesticide hexachlorocyclohexane (α-HCH) is used as tracer in the model development. The structure of the model and processes included are described in detail. The results from a model simulation showing the atmospheric transport for the years 1991 to 1998 are presented and evaluated against measurements. The annual averaged atmospheric concentration of α-HCH for the 1990s is well described by the model; however, the shorter-term average concentration for most of the stations is not well captured. This indicates that the present simple surface description needs to be refined to get a better description of the air-surface exchange proceses of POPs.

scholarly journals Modelling atmospheric transport of α-hexachlorocyclohexane in the Northern Hemispherewith a 3-D dynamical model: DEHM-POP

2004 ◽  
Vol 4 (4) ◽  
pp. 1125-1137 ◽  
Author(s):  
K. M. Hansen ◽  
J. H. Christensen ◽  
J. Brandt ◽  
L. M. Frohn ◽  
C. Geels
Keyword(s):  
Environmental Fate ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Model Simulation ◽  
Model Development ◽  
Average Concentration ◽  
The Arctic ◽  
Atmospheric Concentration ◽  
Surface Exchange ◽  
Exchange Processes

Abstract. The Danish Eulerian Hemispheric Model (DEHM) is a 3-D dynamical atmospheric transport model originally developed to describe the atmospheric transport of sulphur into the Arctic. A new version of the model, DEHM-POP, developed to study the atmospheric transport and environmental fate of persistent organic pollutants (POPs) is presented. During environmental cycling, POPs can be deposited and re-emitted several times before reaching a final destination. A description of the exchange processes between the land/ocean surfaces and the atmosphere is included in the model to account for this multi-hop transport. The α-isomer of the pesticide hexachlorocyclohexane (α-HCH) is used as tracer in the model development. The structure of the model and processes included are described in detail. The results from a model simulation showing the atmospheric transport for the years 1991 to 1998 are presented and evaluated against measurements. The annual averaged atmospheric concentration of α-HCH for the 1990s is well described by the model; however, the shorter-term average concentration for most of the stations is not well captured. This indicates that the present simple surface description needs to be refined to get a better description of the air-surface exchange processes of POPs.

scholarly journals Modelling the impact of climate change on the atmospheric transport and the fate of persistent organic pollutants in the Arctic

2015 ◽  
Vol 15 (11) ◽  
pp. 6549-6559 ◽  
Author(s):  
K. M. Hansen ◽  
J. H. Christensen ◽  
C. Geels ◽  
J. D. Silver ◽  
J. Brandt
Keyword(s):  
Climate Change ◽  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Atmospheric Transport ◽  
Climate Scenario ◽  
The Arctic ◽  
Model Studies ◽  
Environmental Concentrations ◽  
Mean Temperature ◽  
The Impact

Abstract. The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Arctic and their environmental fate within the Arctic. Three sets of simulations were performed, one with present day emissions and initial environmental concentrations from a 20-year spin-up simulation, one with present day emissions and with initial environmental concentrations set to zero and one without emissions but with initial environmental concentrations from the 20-year spin-up simulation. Each set of simulations consisted of two 10-year time slices representing the present (1990–2000) and future (2090–2100) climate conditions. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES (Special Report on Emissions Scenarios) A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 55 % lower across the Northern Hemisphere at the end of the 2090s than in the 1990s. The mass of HCHs within the Arctic was predicted to be up to 38 % higher, whereas the change in mass of the PCBs was predicted to range from 38 % lower to 17 % higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depends on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on the transport of POPs to the Arctic is moderate relative to the effect of proposed changes in emissions, which is confirmed in this study. However, the model studies do not agree on whether climate change acts to reduce or increase environmental concentrations of POPs in the Arctic, and further work is needed to resolve this matter.

scholarly journals Source regions of some persistent organic pollutants measured in the atmosphere at Birkenes, Norway

2009 ◽  
Vol 9 (17) ◽  
pp. 6597-6610 ◽  
Author(s):  
S. Eckhardt ◽  
K. Breivik ◽  
Y. F. Li ◽  
S. Manø ◽  
A. Stohl
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Western Europe ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Measurement Data ◽  
Monitoring And Evaluation ◽  
Source Regions ◽  
Intercontinental Transport ◽  
Source Receptor Relationships

Abstract. A key feature of POPs (Persistent Organic Pollutants) is their potential for long-range atmospheric transport. In order to better understand and predict atmospheric source-receptor relationships of POPs, we have modified an existing Lagrangian transport model (FLEXPART) to include some of the key processes that control the atmospheric fate of POPs. We also present four years (2004–2007) of new atmospheric measurement data for polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) obtained at Birkenes, an EMEP (European Monitoring and Evaluation Programme) site in southern Norway. The model overestimates measured PCB-28 and γ-HCH concentrations by factors of 2 and 8, respectively, which is most likely because the emissions used as input to the model are overestimated. FLEXPART captures the temporal variability in the measurements very well and, depending on season, explains 31–67% (14–62%) of the variance of measured PCB-28 (γ-HCH) concentrations. FLEXPART, run in a time-reversed (adjoint) mode, was used to identify the source regions responsible for the POP loading at the Birkenes station. Emissions in Central Europe and Eastern Europe contributed 32% and 24%, respectively, to PCB-28 at Birkenes, while Western Europe was found to be the dominant source (50%) for γ-HCH. Intercontinental transport from North America contributed 13% γ-HCH. While FLEXPART has no treatment of the partitioning of POPs between different surface media, it was found a very useful tool for studying atmospheric source-receptor relationships for POPs and POP-like chemicals that do not sorb strongly to atmospheric particles and whose atmospheric levels are believed to be mainly controlled by primary sources.

scholarly journals The oceanic biological pump modulates the atmospheric transport of persistent organic pollutants to the Arctic

2012 ◽  
Vol 3 (1) ◽  
Author(s):  
Cristóbal Galbán-Malagón ◽  
Naiara Berrojalbiz ◽  
María-José Ojeda ◽  
Jordi Dachs
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Atmospheric Transport ◽  
The Arctic ◽  
Biological Pump

scholarly journals Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic

2015 ◽  
Vol 15 (5) ◽  
pp. 6509-6535 ◽  
Author(s):  
K. M. Hansen ◽  
J. H. Christensen ◽  
C. Geels ◽  
J. D. Silver ◽  
J. Brandt
Keyword(s):  
Climate Change ◽  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Atmospheric Transport ◽  
Climate Scenario ◽  
The Arctic ◽  
Model Studies ◽  
Environmental Concentrations ◽  
Mean Temperature ◽  
The Difference

Abstract. The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990–2000) and future (2090–2100) climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on the transport of POPs to the Arctic is moderate relatively to the effect of proposed changes in emissions, which is confirmed in this study. However, the model studies do not agree on whether climate change acts to reduce or increase environmental concentrations of POPs in the Arctic, and further work is needed to resolve this matter.

scholarly journals Source regions of some Persistent Organic Pollutants measured in the atmosphere at Birkenes, Norway

2009 ◽  
Vol 9 (3) ◽  
pp. 12345-12383 ◽  
Author(s):  
S. Eckhardt ◽  
K. Breivik ◽  
Y. F. Li ◽  
S. Manø ◽  
A. Stohl
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Western Europe ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Measurement Data ◽  
Monitoring And Evaluation ◽  
Source Regions ◽  
Intercontinental Transport ◽  
Source Receptor Relationships

Abstract. A key feature of POPs (Persistent Organic Pollutants) is their potential for long-range atmospheric transport. In order to better understand and predict atmospheric source-receptor relationships of POPs, we have modified an existing Lagrangian transport model (FLEXPART) to include some of the key processes that control the atmospheric fate of POPs. We also present four years (2004–2007) of new atmospheric measurement data for polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) obtained at Birkenes, an EMEP (European Monitoring and Evaluation Programme) site in Southern Norway. The model overestimates measured PCB-28 and γ-HCH concentrations by factors of 2 and 8, respectively, which is most likely because the emissions used as input to the model are overestimated. FLEXPART captures the temporal variability in the measurements very well and, depending on season, explains 31–67% (14–62%) of the variance of measured PCB-28 (γ-HCH) concentrations. FLEXPART, run in a time-reversed (adjoint) mode, was used to identify the source regions responsible for the POP loading at the Birkenes station. Emissions in Central Europe and Eastern Europe contributed 32% and 24%, respectively, to PCB-28 at Birkenes, while Western Europe was found to be the dominant source (50%) for γ-HCH. Intercontinental transport from North America contributed 13% γ-HCH. While FLEXPART has no treatment of the partitioning of POPs between different surface media, it was found a very useful tool for studying atmospheric source-receptor relationships for POPs and POP-like chemicals that do not sorb strongly to atmospheric particles and whose atmospheric levels are believed to be mainly controlled by primary sources.

Atmospheric transport of persistent organic pollutants (POPs) to Bjørnøya (Bear island)

2007 ◽  
Vol 9 (10) ◽  
pp. 1082 ◽  
Author(s):  
Roland Kallenborn ◽  
Guttorm Christensen ◽  
Anita Evenset ◽  
Martin Schlabach ◽  
Andreas Stohl
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Atmospheric Transport

Breaking the Wall of Monocentric Governance: Polycentricity in the Governance of Persistent Organic Pollutants in the Arctic

2013 ◽  
Vol 5 (1) ◽  
pp. 185-232
Author(s):  
Tahnee Lisa Prior
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Large Scale ◽  
Environmental Governance ◽  
Institutional Design ◽  
The Arctic ◽  
Small Scale ◽  
Governance Capacity ◽  
Human Environment ◽  
Polycentric Governance

Abstract We often mistakenly assume that institutional design will remain effective indefinitely. Complex long-term environmental challenges illuminate the disparity between institutions and state boundaries. While globalization has challenged monocentrism, we must look beyond traditional measures and design resilient governance systems, such as polycentric governance, that combine trust and local expertise in small-scale governance with the governance capacity of large-scale systems. These harness globalization’s benefits and provide solutions for the effects of ecosystem changes. This work examines the lessons – benefits, challenges, limitations, and unanswered questions – that may be learned from polycentric governance in the case of Persistent Organic Pollutants (POPs) in the Arctic, where a polycentric political system has developed as a result of a mismatch in environmental, jurisdictional, and temporal scales. Section One examines characteristics of polycentricity, focusing on actors, multilevel governance, degree of formality, and the nature of interactions. Section Two concentrates on the tools utilized. Section Three applies the outlined framework. Finally, Section Four examines three lessons that global environmental governance may learn from the case study: (1) Peak organizations are effective tools for managing polycentricity, allowing for the inclusion of non-state actors, such as indigenous peoples organizations (2) and epistemic communities (3), in bridging the human-environment nexus.

scholarly journals Atmospheric processes of persistent organic pollutants over a remote lake of the central Tibetan Plateau: Implications for regional cycling

2016 ◽  
Author(s):  
Jiao Ren ◽  
Xiaoping Wang ◽  
Chuanfei Wang ◽  
Ping Gong ◽  
Tandong Yao
Keyword(s):  
Tibetan Plateau ◽  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Secondary Source ◽  
The Tibetan Plateau ◽  
Lake Area ◽  
Nam Co ◽  
Surface Exchange ◽  
Atmospheric Processes ◽  
Water Gas

Abstract. Atmospheric processes (air-surface exchange, and atmospheric deposition and degradation) are crucial for understanding the global cycling and fate of persistent organic pollutants (POPs). However, such assessment over the Tibetan Plateau (TP) remains uncertain. More than 50 % of the Chinese lakes are located on the TP, which exerts a remarkable influence on the regional water, energy, and chemical cycling. In this study, air and water samples were simultaneously collected in Nam Co, a large lake on the TP, to test whether the lake is a "secondary source" or "sink" of POPs. Lower concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were observed in the atmosphere and lake water of Nam Co, while the levels of polycyclic aromatic hydrocarbons (PAHs) were relatively higher. Results of fugacity ratios and chiral signatures both suggest that the lake acted as the net sink of atmospheric hexachlorocyclohexanes (HCHs), following their long-range transport driven by the Indian Monsoon. Different behaviors were observed in the PAHs, which primarily originated from local biomass burning. Acenaphthylene, acenaphthene, and fluorene showed volatilization from the lake to the atmosphere; while other PAHs were deposited into the lake due to the integrated deposition process (wet/dry and air-water gas deposition) and limited atmospheric degradation. As the dominant PAH compound, phenanthrene exhibited a seasonal reversal of air-water gas exchange, which was likely related to the melting of the lake ice in May. The annual input of HCHs from air to the entire lake area (2015 km2) was estimated as 1.9 kg year−1, while those estimated for PAHs can potentially reach up to 550 kg year−1. This study highlights the significance of PAH deposition on the regional carbon cycling in the oligotrophic lakes of the TP.

Sign in / Sign up

Export Citation Format

Share Document