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  • 1.
    Andersson, Pia
    SMHI, Core Services.
    Ballast Water Exchange Areas: Prospects of designating BWE areas in the Baltic Proper2007Report (Other academic)
    Abstract [en]

    Investigations were made to find out if there are areas with suitable environments for ballast water exchange. Suitable conditions may be areas of certain depths (preferably >200 meters) or distance from the coast (preferably >200nm or >50nm).The main focus is on the southern Baltic Proper since it is the area with the highest traffic, it has the largest of the two existing areas in the Baltic Sea >50nm from the coast.The Baltic Sea is not very large and there are nutrients available most of the year. During spring, the biovolume is at its highest, though there are biological activities (even HABs), mainly to the end of the year. The nutrient level is not low enough to prevent indigenous species survival.The very brackish surface waters vary between 5 psu in the Bothnian Sea to 7 psu in the southern Baltic Proper. The difference between fresh and central Baltic Proper water is not large.There is no definite way to say what specific salinity level will kill the BW organisms since there are many different organisms in the BW. As a rule of thumb, there is always a risk that they may survive.There is a high possibility that the surface waters in the BWE areas can be transported to protected areas or the coast and with a prevailing wind of 15 m/s it can take one day to one week, depending on the wind direction.Important assets like fish farms can be gravely affected, depending on the contents of the BW. Also competing or predatory species may cause harm, especially in spawning areas of fish or on native species on the sea bed. There are spawning grounds very close to the southern Baltic Proper proposed BWE area.Discharged pollutants normally affect the protected areas.The wave climate in the Baltic Proper is not very rough, especially when omparing to more open sea areas, hence not posing as high risk to the ship or crew safety.The total annual BWE discharge in the southern Baltic Proper is approximated to 1.9*109 m3.Most probably, the uptake of BW in the BWE area will be comprised of previously discharged BW, but at a low concentration.The BWE areas of interest are small. A ship will have to reduce the speed to be able to complete the exchange within the area.

  • 2.
    Andersson, Pia
    SMHI, Core Services.
    Ballast Water Exchange Areas: Prospects of designating BWE areas in the Skagerrak and the northern Norwegian Trench2007Report (Other academic)
    Abstract [en]

    Investigations were made to find out if there are areas with suitable environments for ballast water exchange (BWE) in the Skagerrak and the Norwegian Trench. Suitable conditions may be areas of certain depths (preferably >200 meters) or distance from the coast (preferably >200 nm or >50 nm). Certain oceanographical, biological and envitonmental issues should also be considered.In the Skagerrak there is no area >50 nm from the coast, but there is a small area within the Swedish territorial waters with depth >200 m. There is an area >50 nm from the coast with depth >200 m in the northern Norwegian Trench.Discharged ballst water in the BWE areas will be transported towards a coast or protected area. The main distance between the potential Skagerrak BWE area and the Natura 2000 areas are 10 to 15 nm.There are strong currents in both BWE areas and discharges could be transported over large areas during the following month. The entire Skagerrak area would be reached. Most parts of the costal zone would be reached within a week. The probability that a BW discharge will reach the nearby Natura 2000 areas is high. The shortest drift time to the protected areas along the Swedish coast and to the Norwegian coast is only a few days.A ship would have to stop or greatly reduce its speed to complete a BWE within the proposed Skagerrak area. In the northern Norwegian Trench, there is no major shipping lane nearby.The wave climate in the Skagerrak may not cause major concern for the safety for large ships. In the northern Norwegian Trench BWE area of interest, wave heights are a significant hazard on board most ships.Nutrient levels are not low enough to efficiently reduce the survival rate of the organisms introduced by BW.Discharged pollutants could normally affect the protected areas if transported to the area.There is no way to say what specific salinity level kill BW organisms since there are many different organisms in the BW. As a rule of thumb, there is always a risk that they may survive. If the organisms are harmful, they can or will affect vulnerable native organisms.The environment at the BWE area or in nearby protected areas, possibly with important assets, can be affected by the BW, although it is dependant on the BW contents. There is a wide variety of what it can contain. If the organisms or pollutants are harmful to a single species or to entire ecosystems, there is a clear risk of affecting protected areas.Important assets like fish and mussel farms can be affected. Competing or predatory species may cause harm, especially in spawning areas of fish or on benthic native species.Circulation of the central Skagerrak surface waters and eddies in the northern Norwegian Coastal Current, increase the risk of ships taking up previously discharged BW. The waters in the BWE areas have strong stratification, which prevents mixing with deep water.The risk of uptake is high, albeit with a reduced concentration. In many of the referenced texts however, the concentrations of the organisms are not of major importance. New organisms may survive and reproduce even at low starting numbers.Most results indicate that the proposed BWE areas are not suitable for BWE with reference to the requirements in the Ballast Water Convention and G14.

  • 3.
    Andersson, Pia
    SMHI, Core Services.
    Drivers of Marine Acidification in the Seas Surrounding Sweden2010Report (Other academic)
    Abstract [en]

    It is of common consensus in the ocean acidification community that the increase of atmospheric CO2 is the main driving force of the downwards pH trends in the worlds oceans. In the stations surrounding Sweden, that is most probably the main underlying factor as well, however the rate of change differs from the oceanic rates and there are different rates of change at different depths and different seasons.To investigate further, four monitoring stations with long time series of pH data in the Kattegat and the Baltic Proper have been analysed both for trends and what the main drivers of the change of pH values for those stations could be.Besides a linear trend analysis, a non parametric trend analysis has been applied to the pH data sets. It appears that the carbonate system generally works in the surface layer where the biologic processes are most active, reducing or prohibiting the decline of pH in most of the evaluated stations. It also seems like the downward trends of pH in most of the remaining water masses are influenced and accelerated by oxygen deficiency and eutrophicated water masses.A multivariate analysis was then performed to see what or what combination of parameters influence the change of the pH values the most. The results from the analysis were either significant or not significant, indicating either more trustworthy or not as trustworthy results. A result showing high correlation for a parameter or a set of parameters that influence pH, in combination with being significant, was then an indication of a trustworthy result.Several parameters were included in this analysis, however some key parameters that perhaps influence the changes of the pH values the most may have been missed due to the lack of available data or knowledge or included in the analysis, but in a wrong way. What this study was able to do, was to use the available parameters at hand and make assumptions on how to prepare the data to be able to combine it with the pH data. The results can give an indication as to how much the parameters influence the pH values out of the included parameters, in the manner they were included.Of all the parameters included in the analysis, O2, O2 saturation, PO4 and DIN were the main parameters influencing the pH values.When looking at what single parameter influence pH the most or the least of the included parameters, a table was put together to display what parameters were ranked to be most important and then second most important and so on to the least important parameter.For all stations, all seasons and all depths, there was a slight tendency for the parameters chl-a, atmospheric CO2, North Atlantic Oscillation Index, precipitation pH, river pH and river alkalinity to be ranked the least important. DIN seemed to be more important at the surface layers than at the bottom layers. Salinity and alkalinity seemed to be more important in the bottom layers than in the surface layers. At all depths, O2, O2 saturation, PO4 and SiO4 seemed to be of higher importance.Another interesting feature was that O2 seemed to be of importance throughout all depths except for the 10-20 meters depth, probably due to high variability at that depth. SiO4 seemed to be more important at the Kattegat station than at the other stations.Chl-a did not seem to be important. Since biological activity should have a large impact on pH, chl-a as included in the analysis, was not a good choice as a representative of the biological activity. O2 and O2 saturation were very much influencing the pH patterns. Perhaps in the top layers, they were better representatives for the biological activity in this analysis.It is also interesting to see the lack of importance of the atmospheric CO2. However, when performing trend analysis, not many pH trends were present at the surface (probably due to the biological and of course chemical/physical processes), opening up for O2, O2 saturation and nutrients to be the dominant parameters.In the report, the monitoring need of acidification parameters from a modelling point of view was addressed. The model validation would be very much improved if the concentrations of organic matter could be validated. Today only measurements of total nitrogen and phosphorus and dissolved inorganic nutrients are available. Including standard observations of particulate organic matter (PON, POP and POC) as well as dissolved organic matter (DON, DOP and DOC) would much improve the possibility to further develop the biogeochemical models.Another recommendation is to do a separate investigation based on the results from the coupled oceanographic and biogeochemical model RCO-SCOBI to recommend possible new stations that are important and not yet covered by the present sampling strategy.To calculate and model the saturation state over depth of calcite and aragonite, of high importance for calcifying organisms, the ions CO32- and Ca2+ need to be determined. Either CO32- directly could be measured, or pCO2 and CT (total carbon) could be measured, calculating the desired ion. Further more, the ion Ca2+ could be directly measured, or if not the highest accuracy is needed, estimations could be made from Ca/salinity relationships.

  • 4.
    Andersson, Pia
    SMHI, Core Services.
    Marine Acidification: On effects and monitoring of marine acidification in the seas surrounding Sweden2008Report (Other academic)
    Abstract [en]

    Surface waters in the world oceans have already experienced a pH reduction of about 0.1 units (OSPAR, 2006.) The trend indicates further decrease of pH and is most probably due to increased uptake of atmospheric CO2 and less buffering capacity of ocean waters. The trend is similar in the waters surrounding Sweden.

  • 5.
    Andersson, Pia
    et al.
    SMHI, Core Services.
    Andersson, Lars
    SMHI, Core Services.
    Long term trends in the seas surrounding Sweden: Part one - Nutrients2006Report (Other academic)
    Abstract [en]

    The main aim of this work is to present data as typical concentration values for different nutrients in the various sea areas, and how these have varied over time. The data presented cover a 30 year period which include both increased eutrophication and years with efforts to reduce antropological input of nutrients to the sea. Trends over 30 years have been calculated for various nutrient parameters. SMHI is the Swedish National Oceanographic Data Centre (NODC) to where several countries have supplied hydrographical data originating from various platforms (vessels, buoys etc.). Stations that have been in regular use for most parts of the last 30 years are included in the analysis. Due to different water characteristics, 14 sea areas are selected to represent the waters surrounding Sweden. In this report all available data from 1976 up till 2005 is used and presented in diagrams and tables. The figures of the parameters are presented as time series. Each parameter is divided into winter, summer, surface and bottom values. In the tables, information on a yearly basis is given to indicate changes that vary over time. Both a classical linear regression method and a non-parametric method (the Mann-Kendall) are used in the trend analysis to account for normal and non-normal distribution of the data. The trend magnitude and significance are also calculated. An overview of the results of significant trends of all the areas in the surface and the bottom for the winter and the summer are presented as arrows in a summary figure.

  • 6.
    Andersson, Pia
    et al.
    SMHI, Core Services.
    Hansson, Martin
    SMHI, Core Services.
    Bjurström, Joel
    Simonsson, Daniel
    Naturtypsbestämning av miljöövervakningsstationer SMHI pelagial miljöövervakning2017Report (Other academic)
    Abstract [en]

    Sampling stations in the national environmental monitoring in the marine environment is not defined when it comes to habitat. This means that the environmental monitoring data collected cannot be properly used in the assessments connected to the Habitats Directive or the Marine Framework Strategy Directive. SwAM has funded and commissioned SMHI to explore the possibilities to in a simple manner classify the habitats for the SMHI monitoring stations. The project was intended to test the equipment and through drop video examine if it is possible, and if so, determine habitats for the open sea stations during the expedition in December, 2016. SMHI has designed a rig and conducted sampling at 11 of 25 monitoring stations. Lighting problems and weather conditions reduced the number of sampled stations. SMHI:s opinion is that the rig, with adjusted light source, is a good tool for visual investigation of the habitats at the monitoring stations in the open sea. However, we have proposed a number of adjustments to the rig to increase the quality of the images and videos and to increase the possibility to carry out further assessments of the material. Most of the images show very fine-grained material like silt / clay. A few species have been recorded and almost no vegetation. Most of the stations did not meet the criteria for the Habitat Directive . At two stations habitat was registered as 1160 Bays and sounds, containing1110 Sandbanks. For HUB Underwater biotopes, AB.H3O Baltic aphotic muddy sediments Characterized by infaunal echinoderms was registered at the station P2 and AB.M4U Baltic aphotic mixed substrate Characterized by no macro community was registered on stations BY5 and BY4. SMHI recommends a review of the collected material together with ArtDatabanken and / or additional expert to ensure the performed assessment, to ensure recommendations and to quality control and define the material to be reported to a data host. SMHI recommend additional visual sampling of the remaining stations, as well as additional sampling on stations where the quality of the image was inadequate, or where ArtDatabanken or a possible additional expert recommend additional sampling. Additional experts may recommend adding sediment sampling to the visual method at some stations. Performing visual sampling of all 25 stations, with one landing per station, will extend the expedition with approximately 11,5-13, hours.

  • 7.
    Cato, Ingemar
    et al.
    Geological Survey of Sweden (SGU),.
    Håkansson, Bertil
    SMHI, Research Department, Oceanography.
    Hallberg, Ola
    Geological Survey of Sweden (SGU),.
    Kjellin, Bernt
    Geological Survey of Sweden (SGU),.
    Andersson, Pia
    SMHI, Core Services.
    Erlandsson, Cecilia
    Geological Survey of Sweden (SGU),.
    Axe, Philip
    SMHI, Research Department, Oceanography.
    A new approach to state the areas of oxygen deficits in the Baltic Sea2008Report (Other academic)
    Abstract [en]

    Sediment and near bottom water oxygen data was evaluated to look for correspondence in anoxic conditions. The SGU and SMHI monitoring data showed high correlation, although the actual data tested proved to be few, coincidence in space was promising. The conclusion drawn from the evaluation is that anoxic postglacial sediments were generally overlaid by near bottom anoxic waters. Hence, it is suggested that the spatial distribution of postglacial clays in the sea-bottom surface can be used, together with near bottom waters oxygen data, to improve spatial distribution in mapping oxygen deficits.Time series of oxygen deficit volume and area was calculated from near bottom data from several sub basins in the southern and central Baltic Proper. In general, hypoxic and anoxic water conditions increased over time but perturbations of improved oxygen conditions linked to major inflow events occurs especially in the Bornholm, Eastern and Western Gotland Basins.The high spatial variability of the postglacial sediments in the Western Gotland Basin compared to other basins indicates that it is indeed sensitive to the area coverage of anoxic waters. In addition, the relatively weak stratification and high variability over time of oxygen deficit make this basin favourable for oxygen improvement engineering methods.In coastal waters several bays along the Östergötland and Småland archipelagos should be further evaluated before selected for ecological engineering methods to improve oxygen conditions.

  • 8.
    Johansen, Marie
    et al.
    SMHI, Core Services.
    Andersson, Pia
    SMHI, Core Services.
    Long term trends in the seas surrounding Sweden: Part two - Pelagic biology2012Report (Other academic)
    Abstract [en]

    This work presents trends in the phytoplankton community. Data on the occurrence of both chlorophyll a (hereafter Chl a) as well as phytoplankton community structure and biovolume are presented.Water transparency in terms of Secchi depth is also presented, as a secondary effect of phytoplankton occurrence. Due to differing water characteristics, 14 sea areas have been selected to represent the waters surrounding Sweden. These areas are identical to the ones chosen in the earlier nutrient report to facilitate comparison. In this report all available data up to and including 2008 are presented as graphs and tables. Each variable is divided into three different seasons: spring, summer and autumn. Trends are only shown for comparable depths. A classical linear regression method is used for phytoplankton groups, Chl a and Secchi depth. The trend magnitude and signifi cance are also calculated for Chl a and Secchi depth. Anoverview of the results are presented for Chl a and Secchi depth.The data presented in this report encourage further development of phytoplankton indicators that not only consider total biovolume or Chl a but rather consider different groups or species in the future. Thesechanges can be important indicators for both eutrophication but can also enhance the understanding of food web interactions.

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