| 1. |
- Hellsten, Sofie, et al.
(författare)
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Base cations deposition in Europe
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The support from the Nordic Council of Ministers, the Working Group for Air and Sea Pollution, has significantly contributed to the development of unified calculations of base cation deposition across Europe with the EMEP model. Previous estimates of base cation deposition in Europe have mainly been based on empirical approaches of varying quality depending on country. The results of the model calculations will be used by CLRTAP and EU to assess the need for reduction of emissions of acidifying air pollutants in agreement with the Gothenburg protocol and NEC. The EMEP model has been extended to calculate the deposition of four base cations; calcium (Ca2+), magnesium (Mg2+), potassium (K+) and sodium (Na+). Natural emissions (from sea salt and wind blown dust) as well as anthropogenic emissions (from combustion and industrial processes) have been considered. Base cations are assumed to behave in a similar manner as primary particles in the atmosphere, and hence the transport and deposition of base cations are considered in the same way as primary particles in the EMEP model. The result of the EMEP modelling was compared with wet deposition fluxes derived from the EMEP and ICP-Forest network, and throughfall measurements from the ICP-Forest network, to assess the robustness of the model calculations. This comparison showed encouraging results. However, it was recognised that the EMEP model can be developed further, particularly regarding the estimates of base cation sources, to correctly quantify the base cation deposition in Europe. Furthermore, to provide a confident assessment of the results of the EMEP model, it is of great importance to further develop and improve the measurement methodologies and the methods applied to estimate dry deposition.
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| 2. |
- Lundén, Jenny, 1971-
(författare)
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Atmospheric DMS in the High Arctic
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During the Arctic summer when the anthropogenic influence is limited, the natural marine source of sulfur in the form of gas-phase dimethyl sulfide viz. DMS(g), is of great importance for cloud formation. The harsh environment of the Arctic makes it difficult to perform in situ measurements of DMS(g) and hence regional model simulations can serve as a complement to increase our understanding of DMS related processes in the Arctic. In this thesis a regional scale meteorological forecast model, extended with DMS(g) calculations, is used to provide a consistent three-dimensional time evolving picture of DMS(g) over the pack-ice region. The analysis focus on meteorological aspects on the horizontal and vertical distribution of DMS(g). Our results show that the amount of DMS(g) over an oceanic source region alone does not determine concentration found over the pack-ice, the prevailing wind also exerts a large influence on the horizontal DMS(g) distribution. The modeled DMS(g) concentrations are advected in plumes in over the pack-ice, which, in combination with the photo-chemical decay, explain the large observed temporal variability of DMS(g) over the pack-ice. The modeled vertical structure show episodes with DMS(g) maxima well above the local boundary layer. Also shown is that DMS(g) maxima can be formed adjacent to frontal zones. In the presence of turbulence DMS(g) can be mixed downwards into the local boundary layer and aid growth to local particles and hence contribute to cloud formation in the boundary layer.
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| 3. |
- Lövblad, Gun, et al.
(författare)
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The deposition of base cations in the Nordic countries
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Base cation deposition from the atmosphere provides, together with weathering, ions for neutralising acidity and, after sufficient reductions of acidifying deposition, a source for replenishing lost base cation pools. In the integrated assessment modelling to support the strategies of pollution abatement, a need for base cation data over Europe has been expressed. Data are needed by the scientists working with acidification effects and recovery of ecosystems. A study has been made on a procedure for mapping base cation deposition over the Nordic countries, with an additional aim of recommendations for base cation mapping on a European scale. The mapping over the Nordic countries was made using the data assimilation part of the MATCH model, run with a resolution of 11x11 km. The mapping was based on monitoring data for concentrations of base cations in air and precipitation in the Nordic and surrounding countries.The influence of base cation deposition in the calculation of critical loads and their exceedance as well as for the dynamic modelling of recovery processes was analysed and base cation deposition was found to be of significant importance. For dynamic modelling, the influence of base cation deposition is less important when using models, which are calibrated with monitoring data. However, in prognoses for the future, it is still very with accurate estimates of the base cation deposition. The procedure for mapping base cation deposition proposed in this project represents an improvement with respect to many previous mapping exercises, because it includes both wet and dry estimates of base cation deposition, and because it handles the decreasing sea salt gradients from the coast towards inland. It is recommended in the report to use the experiences from this Nordic mapping activitiy to initiate a process to compile necessary monitoring and emission data in order to carry out a mapping procedure of base cation deposition at European level.
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| 4. |
- Oliver, Tom Henry, et al.
(författare)
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Knowledge architecture for the wise governance of sustainability transitions
- 2021
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Ingår i: Environmental Science and Policy. - : Elsevier BV. - 1462-9011. ; 126:December, s. 152-163
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Tidskriftsartikel (refereegranskat)abstract
- The need for sustainability transitions is widely recognised, along with a concurrent need for the evolution of knowledge systems to inform more effective policy action. Although there are many new policy targets relating to net zero emissions and other sustainability challenges, cities, regional and national governments are struggling to rapidly develop transformational policies to achieve them. As academics and practitioners who work at the science-policy interface, we identify specific knowledge and competency needs for governing sustainability transitions related to the interlinked phases of envisioning, implementing and evaluating. In short, coordinated reforms of both policy and knowledge systems are urgently needed to address the speed and scale of sustainability challenges. These include embedding systems thinking literacy, mainstreaming participatory policy making, expanding the capacity to undertake transdisciplinary research, more adaptive governance and continuous organisational learning. These processes must guide further knowledge development, uptake and use as part of an iterative and holistic process. Such deep-seated change in policy-knowledge systems will be disruptive and presents challenges for traditional organisational models of knowledge delivery, but is essential for successful sustainability transformations.
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| 5. |
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