| 1. |
- Gustafsson, Bo G., et al.
(author)
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Reconstructing the Development of Baltic Sea Eutrophication 1850-2006
- 2012
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In: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 41:6, s. 534-548
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Journal article (peer-reviewed)abstract
- A comprehensive reconstruction of the Baltic Sea state from 1850 to 2006 is presented: driving forces are reconstructed and the evolution of the hydrography and biogeochemical cycles is simulated using the model BALTSEM. Driven by high resolution atmospheric forcing fields (HiResAFF), BALTSEM reproduces dynamics of salinity, temperature, and maximum ice extent. Nutrient loads have been increasing with a noteworthy acceleration from the 1950s until peak values around 1980 followed by a decrease continuing up to present. BALTSEM shows a delayed response to the massive load increase with most eutrophic conditions occurring only at the end of the simulation. This is accompanied by an intensification of the pelagic cycling driven by a shift from spring to summer primary production. The simulation indicates that no improvement in water quality of the Baltic Sea compared to its present state can be expected from the decrease in nutrient loads in recent decades.
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| 2. |
- Karlsson, Per Erik, et al.
(author)
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Biomass burning in eastern Europe during spring 2006 caused high deposition of ammonium in northern Fennoscandia
- 2013
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In: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 176, s. 71-79
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Journal article (peer-reviewed)abstract
- High air concentrations of ammonium were detected at low and high altitude sites in Sweden, Finland and Norway during the spring 2006, coinciding with polluted air from biomass burning in eastern Europe passing over central and northern Fennoscandia. Unusually high values for throughfall deposition of ammonium were detected at one low altitude site and several high altitude sites in north Sweden. The occurrence of the high ammonium in throughfall differed between the summer months 2006, most likely related to the timing of precipitation events. The ammonia dry deposition may have contributed to unusual visible injuries on the tree vegetation in northern Fennoscandia that occurred during 2006, in combination with high ozone concentrations. It is concluded that long-range transport of ammonium from large-scale biomass burning may contribute substantially to the nitrogen load at northern latitudes. (C) 2013 Elsevier Ltd. All rights reserved.
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| 3. |
- Lövblad, Gun, et al.
(author)
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The deposition of base cations in the Nordic countries
- 2004
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Reports (other academic/artistic)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. |
- Meier, Markus, et al.
(author)
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Comparing reconstructed past variations and future projections of the Baltic sea ecosystem first results from multi model ensemble simulations
- 2012
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In: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 7:3, s. 034005-
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Journal article (peer-reviewed)abstract
- Multi-model ensemble simulations for the marine biogeochemistry and food web of the Baltic Sea were performed for the period 1850-2098, and projected changes in the future climate were compared with the past climate environment. For the past period 1850-2006, atmospheric, hydrological and nutrient forcings were reconstructed, based on historical measurements. For the future period 1961-2098, scenario simulations were driven by regionalized global general circulation model (GCM) data and forced by various future greenhouse gas emission and air-and riverborne nutrient load scenarios (ranging from a pessimistic 'business-as-usual' to the most optimistic case). To estimate uncertainties, different models for the various parts of the Earth system were applied. Assuming the IPCC greenhouse gas emission scenarios A1B or A2, we found that water temperatures at the end of this century may be higher and salinities and oxygen concentrations may be lower than ever measured since 1850. There is also a tendency of increased eutrophication in the future, depending on the nutrient load scenario. Although cod biomass is mainly controlled by fishing mortality, climate change together with eutrophication may result in a biomass decline during the latter part of this century, even when combined with lower fishing pressure. Despite considerable shortcomings of state-of-the-art models, this study suggests that the future Baltic Sea ecosystem may unprecedentedly change compared to the past 150 yr. As stakeholders today pay only little attention to adaptation and mitigation strategies, more information is needed to raise public awareness of the possible impacts of climate change on marine ecosystems.
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| 5. |
- Ruoho-Airola, Tuija, et al.
(author)
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Atmospheric Nutrient Input to the Baltic Sea from 1850 to 2006 : A Reconstruction from Modeling Results and Historical Data
- 2012
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In: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 41:6, s. 549-557
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Journal article (peer-reviewed)abstract
- In this study, a consistent basin-wise monthly time series of the atmospheric nutrient load to the Baltic Sea during 1850-2006 was compiled. Due to the lack of a long time series (1850-1960) of nutrient deposition to the Baltic Sea, the data set was compiled by combining a time series of deposition data at the Baltic Nest Institute from 1970 to 2006, published historical monitoring data and deposition estimates, as well as recent modeled Representative Concentration Pathways (RCP) emission estimates. The procedure for nitrogen compounds included estimation of the deposition in a few intermediate reference years, linear interpolation between them, and the decomposition of annual deposition into a seasonal deposition pattern. As no reliable monitoring results were found for the atmospheric deposition of phosphorus during the early period of our study, we used published estimates for the temporal and spatial pattern of the phosphorus load.
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| 6. |
- Savchuk, Oleg P., et al.
(author)
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Long-term reconstruction of nutrient loads to the Baltic Sea, 1850-2006
- 2012
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Reports (other academic/artistic)abstract
- A common intention in ecosystem approach to management of marine resources worldwide has become a ‘restoration of ecosystems’ to some better shape. Although appealing, this political, rather vague aim has to be made more precise in order to be useful as a management objective. Therefore, a crucial role in defining EO, EQS, ES, ET, and similar characteristics set forward by, e.g. BSAP, MSFD, ND, UWWTD, and WFD as well as by many other acronyms to come, belongs to some conventional numbers that are considered as representing so-called background or reference conditions, which existed before significant man-made disturbances. At the Baltic Sea, experiencing human influence for centuries, quantification of the reference conditions and designing of desired state of restored marine ecosystems is complicated by both the uncertainty of which past times might be considered as reference times and the lack of essential observations from those times. One of the major, if not the only reliable method for reconstruction of the reference trophic state is it’s simulation with biogeochemical models forced by the appropriate boundary conditions, including external nutrient inputs corresponding to the reference time interval. Once reconstructed, estimates of such “pristine” or, better to say, “pre-industrial” loads and their historical development can also be used both to test models’ capabilities in reproducing pre-eutrophied state of the Baltic Sea and to study the very development of its eutrophication. Plausible solution of these problems gives more credibility to simulated responses of the marine ecosystems to scenarios of load reductions. For the Baltic Sea, such approach was initiated by Schernewski and Neumann (2005) and Savchuk et al. (2008) and further developed in the ECOSUPPORT Project (Gustafsson et al., 2012), where also a reconstruction of nutrient inputs since 1850 was briefly described. In order to facilitate distribution of reconstructed inputs and their usage, here we describe the process of reconstruction in more detail and make available the full data sets in digital form. The reconstructed external nutrient inputs comprise two periods. Land loads and atmospheric deposition in 1970-2006 are based on the best available data with sufficiently high coverage and resolution (Savchuk et al., 2012), while temporal dynamics over 1850-1970 were interpolated between estimates prescribed for a few fixed years. Similarly to the dataset for 1970-2006, the reconstructed inputs are aggregated according to the spatial segmentation of the Baltic Sea (Fig. 1) currently implemented in the biogeochemical model BALTSEM (BAltic sea Long-Term large Scale Eutrophication Model).
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