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  • 151.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    Internal loading: A new solution to an old problem in aquatic sciences.2004In: Lakes & Reservoirs: Research & Management, Vol. 98, p. 3-23Article in journal (Refereed)
  • 152.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Kvävereningen är ansvarslös.: UNT-Debatt, 2004-04-182008Other (Other (popular scientific, debate etc.))
  • 153.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Lake environments.: Chapter 42007In: Environmental Sedimentology, Blackwell Publishing,Oxford, , 2007, p. 109-143Chapter in book (Refereed)
  • 154.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Lakes – form and function.2004Book (Refereed)
  • 155.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Protocols and motivations for selected operational effect variables to be generally used to address problems and realisitc remedial measures for coastal eutrophication.: Deliverable 2.5.1.2006Report (Other scientific)
  • 156.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Radioaktiva ämnen i insjöfisk – förändringar i tiden.2006In: Strålskyddsnytt, no 1, p. 26-28Article in journal (Refereed)
  • 157.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Report on classification of coastal zones.: Deliverable D6.2.1.2006Report (Other scientific)
  • 158.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Suspended particulate matter in lakes, rivers and marine systems.2006Book (Refereed)
  • 159.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    The importance of lake morphometry and catchment characteristics in limnology – ranking based on statistical analyses.2005In: Hydrobiologia, Vol. 541, p. 117-137Article in journal (Refereed)
  • 160.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    The importance of lake morphometry for the structure and function of lakes.2005In: Internat. Rev. Hydrobiol.,, Vol. 90, p. 433-461Article in journal (Refereed)
  • 161.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    The relationship between salinity, suspended particulate matter and water clarity in aquatic systems2006In: Ecological Research, Vol. 21, p. 75-90Article in journal (Refereed)
  • 162.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Tools and criteria for sustainable coastal ecosystem management – with examples from the Baltic Sea and other aquatic systems.2008Book (Refereed)
  • 163.
    Håkanson, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Åke Sundborg, 1921-2007. In memoriam2008Other (Other (popular scientific, debate etc.))
  • 164.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Blenckner, Thorsten
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas C.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Hellström, Sara-Sofia
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    The influence of calcium on the chlorophyll-phosphorus relationship and lake Secchi depths.2005In: Hydrobiologia, Vol. 537, p. 111-123Article in journal (Refereed)
  • 165.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. LUVA.
    Blenckner, Thorsten
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. LUVA.
    Malmaeus, J. Mikael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. LUVA.
    New, general methods to define the depth separating surface water from deep water, outflow and internal loading for mass-balance models for lakes.2004In: Ecol. Modelling, Vol. 175, no 339-352Article in journal (Refereed)
  • 166.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    Boulion, V.
    Empirical and dynamical models of production and biomasses of benthic algae in lakes.2004In: Hydrobiologia, Vol. 522, p. 75-97Article in journal (Refereed)
  • 167.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Bryhn, Andreas C.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Det finns inga genvägar till att rena Östersjön!2007Other (Other (popular scientific, debate etc.))
  • 168.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas C.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Goals and remedial strategies for water quality and wildlife management in a coastal lagoon: a case-study of Ringkobing Fjord, Denmark2008In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 86, no 3, p. 498-519Article in journal (Refereed)
    Abstract [en]

    The aim of this work is (1) to discuss approaches and tools to set management goals using operational indicators for coastal management (i.e., indicators that are easy to measure, understand and predict) and validated predictive models and (2) to discuss remedial strategies for sustainable coastal management regarding water quality and the abundance of fish, waterfowl and large aquatic plants. These approaches Lire exemplified using data from Ringkobing Fjord, Denmark, which has undergone two major regime shifts during the last decades. This work discusses the changes taken place during the period from 1980 to 2004 (when there are good empirical data). For Ringkobing Fjord, which is a very shallow, well-oxygenated lagoon dominated by resuspension processes, we have targeted on the following operational indicators, which are meant to reflect seasonal median values for the entire defined coastal area (the ecosystem scale) and not conditions at individual sites or data from shorter time periods: Secchi depth (as a standard measure of water clarity) and chlorophyll-a concentrations (as a key measure of algal biomass). The operational indicators are regulated by a set of standard abiotic factors, such as salinity, suspended particulate matter (SPM), nutrient concentrations (N and P), coastal morphometry and water exchange. Such relationships are quantified using well-tested, general quantitative models, which illustrate how these indicators are interrelated and how they reflect fundamental aspects of coastal ecosystems. We demonstrate that the regime shift in the lagoon can be modelled and quantitatively explained and is related to changes in salinity and nutrient inflow. A very important threshold is linked to increased salinities in the lagoon. For: example, when the mean annual salinity is higher than about 9.5 parts per thousand, large numbers of saltwater species of clams can survive and influence the structure and function of the ecosystem in profound ways. The model also illustrates the dynamic response to changes in nutrient loading. We have presented several management strategies with the goal of keeping the Secchi depth at 2 m, which would stimulate the growth of higher aquatic plants, which are fundamental for fish production and bird abundance in the lagoon. Given the fact that the Secchi depth depends on many variable factors (temperature, TP-inflow from land, salinity, changes in biomasses of macrophytes and clams, which are accounted for in these simulations), our results indicate that in practice it will likely be very difficult to reach that goal. However; it would be realistic to maintain a Secchi depth of 1.5m if the variability in salinity is minimized and the mean salinity is kept at about 10.2 parts per thousand.

  • 169.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas C.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Modeling the foodweb in coastal areas: a case study of Ringkobing Fjord, Denmark2008In: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 23, no 2, p. 421-444Article in journal (Refereed)
    Abstract [en]

    This work utilizes the CoastWeb model, a foodweb model for coastal areas that also includes a mass-balance model (CoastMab) for phosphorus and many abiotic/biotic interactions, to study the development in Ringkobing Fjord, Denmark, from 1985 to 2004. This shallow coastal lagoon has an area of 300 km(2) and a mean depth of 1.9 m. The water exchange between the lagoon and the North Sea is regulated by a sluice. In 1996 there was a major regime shift in this lagoon with drastic reductions in chlorophyll-a concentrations, significant increases in water clarity (Secchi depth) and major changes in the number and biomass of clams as well as in macrophyte cover. Regime shifts is a "hot" topic in aquatic ecology and in this work the CoastWeb model is used as a tool to understand and quantify the causes behind this regime shift. The CoastWeb model is general and can also be used for other coastal areas. The basic model calculates monthly production values and changes in biomasses of ten functional groups of organisms (phytoplankton, bacterioplankton, herbivorous, and predatory zooplankton, benthic algae, macrophytes, jellyfish, zoobenthos and prey and predatory fish) and in Ringkobing Fjord, also for clams (Mya arenaria). In spite of its complexity, the model is relatively simple to use, since all driving variables may be readily accessed from maps or monitoring programs. The model includes much abiotic/biotic feedback and it can also be used to address other causes for regime shifts other than the changes in salinity and nutrient inflow, which have caused the changes in Ringkobing Fjord. The model has previously been tested for more than 20 smaller coastal areas and was shown to predict variations in foodweb characteristics very well. The focus of this paper is on temporal variations within one well-studied coastal area. The paper compares modeled values to empirical data for Ringkobing Fjord and discusses fundamental ecosystem features such as regime shifts and compensatory effects in a way that is not practically feasible without the use of quantitative models.

  • 170.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas C.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Blenckner, Thorsten
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Operational effect variables and functional ecosystem classifications: a review on empirical models for aquatic systems along a salinity gradient2007In: International review of hydrobiology, ISSN 1434-2944, E-ISSN 1522-2632, Vol. 92, no 3, p. 326-357Article, review/survey (Refereed)
    Abstract [en]

    This paper presents a comparative study based on a very comprehensive set of empirical data from many international data bases including fresh water systems, coastal brackish water areas and marine coastal areas. We present a general trophic level classification system (oligotrophic, mesotrophic, eutrophic and hypertrophic categories) for sites/areas characterised by a wide range of salinities. This classification system targets on the following operational effect variables (bioindicators), which are meant to reflect key structural and functional aspects of aquatic ecosystems and characteristic (median) values for entire defined areas (the ecosystem scale) for the growing season: Secchi depth (as a standard measure of water clarity), chlorophyll-a concentrations (a measure of primary phytoplankton biomass), the oxygen saturation in the deep-water zone (an indicator reflecting sedimentation, oxygen consumption, oxygen concentrations and the habitat conditions for zoobenthos, an important functional group) and the macrophyte cover (an important variable for the bioproduction potential, including fish production, and the "biological value" of aquatic systems). For a wide range of systems, these bioindicators can be predicted using practically useful models, i.e., models based on variables that can be accessed from standard monitoring programs and maps. These bioindicators are regulated by a set of abiotic factors, such as salinity, suspended particulate matter (SPM), nutrient concentrations (N and P), morphometry and water exchange. Empirical data ultimately form the basis for most ecological/environmental studies and this work uses maybe the most comprehensive data set ever related to trophic level conditions. It also gives compilations of empirically-based (statistical) models quantifying how the variables are interrelated and how they reflect fundamental aspects of aquatic ecosystems.

  • 171.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas C.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Eklund, Jenny M.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Modelling phosphorus and suspended particulate matter in Ringkobing Fjord to understand regime shifts2007In: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 68, no 1-2, p. 65-90Article in journal (Refereed)
    Abstract [en]

    The focus in this work is on the conditions in Ringkøbing Fjord (Denmark), where there have been major regime shifts during the last 30 years. The regime shift in the 1990s is discussed in this paper and concerns reductions in nutrient input from land and changes in salinity. The changes in these abiotic have drastically influenced the structure and functioning of the ecosystem [e.g., in phytoplankton production, water clarity, macrophyte cover and biomass of clams]. This work concerns the modelling and understanding of such changes and the aim is also to consider patterns in variability in the data that may explain the regime shift. The model used is a general, dynamic process-based mass-balance model for total phosphorus (TP) and suspended particulate matter (SPM). The model uses ordinary differential equations (the ecosystem scale). The calculation time is 1 month to reflect seasonal variations. We quantify, e.g., sedimentation, resuspension, diffusion, mixing and retention. The model has previously been tested for coastal areas of different character and shown to predict TP, SPM, Secchi depth, chlorophyll and the oxygen saturation in the deep-water zone very well (within the uncertainty bands of the empirical data). We show that the model, with new calculation routines for macrophytes and clams, also describes the conditions in Ringkøbing Fjord well, which means that the model is a useful general tool for interpretations of changes in coastal ecosystems. The model is simple to apply in practice since all driving variables may be readily accessed from maps or regular monitoring programs.

  • 172.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Bryhn, Andreas C.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Eklund, Jenny M.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Stenström-Khalili, Maria I.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Practical tests and applications of a validated mass-balance model for phosphorus in coastal areas with a special focus on criteria for thresholds.: Manuscripts related to D.2.5.1 and D.2.5.2. submitted for publication in international journals. Delivery D2.5.32007Report (Other scientific)
  • 173.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A dynamic mass-balance model for phosphorus in lakes with a focus on criteria for applicability and boundary conditions2008In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 187, no 1-4, p. 119-147Article in journal (Refereed)
    Abstract [en]

    This paper presents an improved version of a general, process-based mass-balance model (LakeMab/LEEDS) for phosphorus in entire lakes (the ecosystem scale). The focus in this work is set on the boundary conditions, i.e., the domain of the model, and critical tests to reveal those boundary conditions using data from a wide limnological range. The basic structure of the model, and many key equations have been presented and motivated before, but this work presents several new developments. The LakeMab-model is based on ordinary differential equations regulating inflow, outflow and internal fluxes and the temporal resolution is one month to reflect seasonal variations. The model consists of four compartments: surface water, deep water, sediment on accumulation areas and sediment on areas of erosion and transportation. The separation between the surface-water layer and the deep-water layer is not done from water temperature data, but from sedimentological criteria (from the theoretical wave base, which regulates where wind/wave-induced resuspension of fine sediments occurs). There are algorithms for processes regulating internal fluxes and internal loading, e.g., sedimentation, resuspension, diffusion, mixing and burial. Critical model tests were made using data from 41 lakes of very different character and the results show that the model could predict mean monthly TP-concentrations in water very well (generally within the uncertainty bands given by the empirical data). The model is even easier to apply than the well-known OECD and Vollenweider models due to more easily accessed driving variables.

  • 174.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bryhn, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Malaeus, Mikael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Ändra strategin för Östersjön.2005In: Uppsala Nya Tidning, no 9/3-05, p. 1-14Article in journal (Other (popular scientific, debate etc.))
  • 175.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Bryhn, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Rydberg, Lars
    Stigebrandt, Anders
    Walin, Gösta
    Karlsson, Magnus
    Malmaeus, Mikael
    Skattemiljarder kastas i Östersjön utan nytta.2006In: DN-debatt, Vol. 11 mars, p. 19Article in journal (Other (popular science, discussion, etc.))
  • 176.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Eckhell, Jan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Suspended particulate matter (SPM) in the Baltic – New empirical data and models.2005In: Ecol. Modelling, Vol. 189, p. 130-150Article in journal (Refereed)
  • 177.
    Håkanson, Lars
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Eklund, Jenny M.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A dynamic mass balance model for phosphorus fluxes and concentrations in coastal areas2007In: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 22, no 2, p. 296-320Article in journal (Refereed)
    Abstract [en]

    This paper presents a general, process-based mass balance model (CoastMab) for total phosphorus (TP) in defined coastal areas (at the ecosystem scale). The model is based on ordinary differential equations and calculates inflow, outflow and internal fluxes on a monthly basis. It consists of four compartments: surface water, deep water, erosion/transportation areas for fine sediments and accumulation areas for fine sediments. The separation between surface water and deep water is not done based on water temperature, but on sedimentological criteria instead (from the theoretical wave base). There are algorithms for all major internal TP fluxes (sedimentation, resuspension, diffusion, mixing and burial). Validations were performed using data from 21 different Baltic coastal areas. The results show that the model predicts monthly TP in water and chlorophyll a very well (generally within the uncertainty bands of the empirical data). The model has also been put through sensitivity tests, which show that the most important factor regulating the predictions of the model is generally the TP concentration in the sea beyond the coast. The model is simple to apply, since all driving variables may be accessed from maps or monitoring programs. The driving variables include coastal area, section area (between the defined coastal area and the adjacent sea), mean and maximum depths, latitude (used to predict water temperatures, stratification and mixing), salinity and TP concentration in the sea. Many of the model structures are general and could be used for areas other than those included in this study, e.g., for open coasts, estuaries or tidal coasts, as well as for other substances than phosphorus.

  • 178.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Eklund, Jenny M.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    A validated mass-balance model for phosphorus in coastal areas with a special focus on criteria for thresholds.: Delivery D2.5.22007Report (Other scientific)
  • 179.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Gyllenhammar, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Setting fish quotas based on holistic ecosystem modelling including environmental factors and foodweb interactions – a new approach.2005In: Aquatic Ecology, Vol. 39, p. 325-352Article in journal (Refereed)
  • 180.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    Gyllenhammar, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    Brolin, Angelica
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    A dynamic model to predict sedimentation and suspended particulate matter in coastal areas.2004In: Ecological Modelling, Vol. 175, p. 353-384Article in journal (Refereed)
  • 181.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    Lindgren, Dan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVAL.
    A protocol (computer codes, equations and motivations) for a general operational foodweb-model for coastal areas which can be run by readily accessible driving variables from maps and monitoring programs incorporating the eutrophication model discussed in WP5. Manuscript related to D.2.7.1. to be submitted for publication in international journal.: Deliverables D2.7.1. and D.2.7.22007Report (Other scientific)
  • 182.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Malmaeus, J. Mikael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Basic concepts related to uncertainty in empirical data regulating predictive power of mass-balance models2005In: New trends in ecology research, Nova Science Publishers, New York , 2005, p. 37-70Chapter in book (Refereed)
  • 183.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Malmaeus, Mikael
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Samordna åtgärderna runt Östersjön – och satsa på fosfor.2006In: Östersjön – hot och hopp, 2006, p. 101-112Chapter in book (Other (popular scientific, debate etc.))
  • 184.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Mikrenska, Maya
    Petrov, Krassimir
    Foster, Ian
    Suspended particulate matter (SPM) in rivers: empirical data and models.2005In: Ecol. Modelling, Vol. 183, p. 357-382Article in journal (Refereed)
  • 185.
    Håkanson, Lars
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Air and Water Sciences.
    Roberts, Roland
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Geofysik.
    Bygg ut kärnkraften som en nödlösning2004Other (Other (popular scientific, debate etc.))
  • 186. Håkansson, Lena
    et al.
    Briner, Jason
    Alexanderson, Helena
    Aldahan, Ala
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Possnert, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Ion Physics.
    10Be ages from central east Greenland constrain the extent of the Greenland ice sheet during the Last Glacial Maximum2007In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 26, no 19-21, p. 2316-2321Article in journal (Refereed)
    Abstract [en]

    Traditional ice sheet reconstructions have suggested two distinctly different ice sheet regimes along the East Greenland continental margin during the Last Glacial Maximum (LGM): ice to the shelf break south of Scoresby Sund and ice extending no further than to the inner shelf at and north of Scoresby Sund. We report new 10Be ages from erratic boulders perched at 250 m a.s.l. on the Kap Brewster peninsula at the mouth of Scoresby Sund. The average 10Be ages, calculated with an assumed maximum erosion rate of 1 cm/ka and no erosion (respectively, 17.3±2.3 ka and 15.1±1.7 ka) overlap with a period of increased sediment input to the Scoresby Sund fan (19–15 ka). The results presented here suggest that ice reached at least 250 m a.s.l. at the mouth of Scoresby Sund during the LGM and add to a growing body of evidence indicating that LGM ice extended onto the outer shelf in northeast Greenland.

  • 187. Höglund, Lars Olof
    et al.
    Herbert Jr., Roger
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Luft- och vattenlära.
    MiMi – Performance Assessment main report: Report from the MISTRA research program Mitigation of the environmental impact from mining waste (MiMi)2004Book (Other scientific)
  • 188. Höglund, Lars Olof
    et al.
    Herbert, Roger
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Luft- och vattenlära.
    MiMi – Performance Assessment main report: Report from the MISTRA research program Mitigation of the environmental impact from mining waste (MiMi)2004Report (Other scientific)
  • 189.
    Högström, Martin
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Wind Climate Estimates - Validation of Modelled Wind Climate and Normal Year Correction2007Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Long time average wind conditions at potential wind turbine sites are of great importance when deciding if an investment will be economically safe. Wind climate estimates such as these are traditionally done with in situ measurements for a number of months. During recent years, a wind climate database has been developed at the Department of Earth Sciences, Meteorology at Uppsala University. The database is based on model runs with the higher order closure mesoscale MIUU-model in combination with long term statistics of the geostrophic wind, and is now used as a complement to in situ measurements, hence speeding up the process of turbine siting. With this background, a study has been made investigating how well actual power productions during the years 2004-2006 from 21 Swedish wind turbines correlate with theoretically derived power productions for the corresponding sites.

    When comparing theoretically derived power productions based on long term statistics with measurements from a shorter time period, correction is necessary to be able to make relevant comparisons. This normal year correction is a main focus, and a number of different wind energy indices which are used for this purpose are evaluated. Two publicly available (Swedish and Danish Wind Index) and one derived theoretically from physical relationships and NCEP/NCAR reanalysis data (Geostrophic Wind Index). Initial testing suggests in some cases very different results when correcting with the three indices and further investigation is necessary. An evaluation of the Geostrophic Wind Index is made with the use of in situ measurements.

    When correcting measurement periods limited in time to a long term average, a larger statistical dispersion is expected with shorter measurement periods, decreasing with longer periods. In order to investigate this assumption, a wind speed measurement dataset of 7 years were corrected with the Geostrophic Wind Index, simulating a number of hypothetical measurement periods of various lengths. When normal year correcting a measurement period of specific length, the statistical dispersion decreases significantly during the first 10 months. A reduction to about half the initial statistical dispersion can be seen after just 5 months of measurements.

    Results show that the theoretical normal year corrected power productions in general are around 15-20% lower than expected. A probable explanation for the larger part of this bias is serious problems with the reported time-not-in-operation for wind turbines in official power production statistics. This makes it impossible to compare actual power production with theoretically derived without more detailed information. The theoretically derived Geostrophic Wind Index correlates well to measurements, however a theoretically expected cubed relationship of wind speed seem to account for the total energy of the wind. Such an amount of energy can not be absorbed by the wind turbines when wind speed conditions are a lot higher than normal.

  • 190.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Hunt, Julian
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Theory and measurements for turbulence spectra and variances in the near neutral surface layer2002In: Bound,-Layer Meteorol., Vol. 103, p. 101:124-Article in journal (Refereed)
  • 191.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A case study of two-dimensional stratified turbulence1999In: J. Atm. Sci., Vol. 56, p. 959-976Article in journal (Refereed)
  • 192.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Luft och vattenlära.
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. Luft och vattenlära.
    : Accuracy of sonic anemometers: Laminar wind-tunnel calibrations compared to atmospheric in situ calibrations against a reference instrument.2004In: Boundary-Layer Meteorology, Vol. 111, no 1, p. 33-54Article in journal (Refereed)
  • 193.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    The roughness length for sensible heat and matter over the sea during high wind conditions.2006In: GTP Conference on Turbulence and Scalar Transport in Roughness Sublayers, Boulder, USA,26-28 September 2006, 2006Conference paper (Refereed)
  • 194.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bergström, Hans
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Calculation of wind speed variation with height over the sea2006In: Wind Engineering, Vol. 30, no 4, p. 269-286Article in journal (Refereed)
  • 195.
    Högström, Ulf
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Smedman, Ann-Sofi
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Hunt, Julian
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A top-down theory for the neutral atmospheric surface layercompared with experiments2004In: IUTAM Symposium on Reynolds Number Scaling in Turbulent Flow, Kluwer Academic Publisher , 2004, p. 324-Chapter in book (Refereed)
  • 196. Iorgulescu, I.
    et al.
    Beven, Keith J.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Musy, A.
    Flow, mixing, and displacement in using a data-based hydrochemical model to predict conservative tracer data2007In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 43, no 3, p. W03401-Article in journal (Refereed)
    Abstract [en]

    We extend the data-based hydrochemical model of Iorgulescu et al. (2005), able to simulate discharge and reactive chemical tracer concentrations (silica and calcium) in streamflow for subcatchments of the Haute-Mentue research basin (Switzerland), to the prediction of additional δ 18O values treated as a conservative tracer. The hydrochemical model is based on a parameterization of three runoff components (direct precipitation (DP), acid soil water (AS), and deep groundwater (GW)) in a chemical mixing model. Each component is modeled through an identical structure consisting of a nonlinear gain and a linear transfer function with two reservoirs (fast/slow) in parallel having a constant partition between them. We formulate a set of hypotheses concerning the isotope characterization of each component to provide additional information about how new rainfall inputs are processed in the hydrological response of the catchment. In particular, the AS component is modeled through a nested structure of hypotheses (models) of increasing complexity. It will be shown that hydrological processes in the hillslope associated with the DP, AS, and GW components are especially effective in filtering of higher-frequency fluctuations in precipitation isotopic ratios at the intraevent, interevent/seasonal, and annual/multiannual timescales. The highly nonlinear and nonstationary AS component represents predominantly “recent” water stored in the upper decimeters of the soil profile. Results also suggest that subsurface pathways are significant for the DP component. A local flow path mechanism is proposed for explaining the large fluxes of subsurface flows.

  • 197.
    Israelsson, Sven
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Long-term measurements of the vertical electrical potential gradient in the atmospheric surface layers2007In: International conference on atmospheric electricity ICAE, 2007Conference paper (Other (popular scientific, debate etc.))
    Abstract [en]

    : A long series of measurements of the surface potential gradient have been made since 1962 in Sweden in the Marsta Observatory (59◦56 N; 17◦35 W) located in rural area 10 km north of Uppsala. Nearest forest is located more than 1 km from the observatory, which provides undisturbed micro-meteorological conditions. There are no industrial establishments around the observatory. A modifed atmospheric electrical station of the Kasemir–Dolezalek construction is used. During long periods other electric and meteorological parameters are measured.

    The study shows that the effect of local air pollution appears essentially less than at other evaluated continental atmospheric electric stations. The diurnal variations at Marsta are well correlated with the Carnegie curve during winter and ill correlated during summer.

    Our long-term measurements during the years 1962—2002 show no pronounced changes in the vertical potential gradiant in winter or during the year. Other previous long-term measurements in Europe, however, show a long-term decrease in the vertical potential gradient. The differences in the observations can be due to changes in the surroundings of the observation sites. Even local changes in the concentration of air polution can explain the differences. Baloon measurements of the ionospheric potential from 50 years measurements at different places over the globe show no long-term trend.

  • 198. Jacob, Carstensen
    et al.
    Emilio, Hernandez-Garcia
    Lars, Håkanson
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science. LUVA.
    Terminology list for threshold modelling, identification and uncertainty evaluation.2006Report (Other scientific)
  • 199. Jiang, T.
    et al.
    Chen, Y.D.
    Xu, Chong-yu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Chen, X.H.
    Chen, X.
    Singh, V.P.
    Comparison of hydrological impacts of climate change simulated by six hydrological models in the Dongjiang Basin, South China2007In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 336, no 3-4, p. 316-333Article in journal (Refereed)
    Abstract [en]

    Large differences in future climatic scenarios found when different global circulation models (GCMs) are employed have been extensively discussed in the scientific literature. However, differences in hydrological responses to the climatic scenarios resulting from the use of different hydrological models have received much less attention. Therefore, comparing and quantifying such differences are of particular importance for the water resources management of a catchment, a region, a continent, or even the globe. This study investigates potential impacts of human-induced climate change on the water availability in the Dongjiang basin, South China, using six monthly water balance models, namely the Thornthwaite–Mather (TM), Vrije Universitet Brussel (VUB), Xinanjiang (XAJ), Guo (GM), WatBal (WM), and Schaake (SM) models. The study utilizes 29-year long records of monthly streamflow and climate in the Dongjiang basin. The capability of the six models in simulating the present climate water balance components is first evaluated and the results of the models in simulating the impact of the postulated climate change are then analyzed and compared. The results of analysis reveal that (1) all six conceptual models have similar capabilities in reproducing historical water balance components; (2) greater differences in the model results occur when the models are used to simulate the hydrological impact of the postulated climate changes; and (3) a model without a threshold in soil moisture simulation results in greater changes in model-predicted soil moisture with respect to alternative climates than the models with a threshold soil moisture. The study provides insights into the plausible changes in basin hydrology due to climate change, that is, it shows that there can be significant implications for the investigation of response strategies for water supply and flood control due to climate change.

  • 200.
    Johansson, Cecilia
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    Bergström, Hans
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Air and Water Science.
    A study of the wind field above Gotland2005Report (Other scientific)
1234567 151 - 200 of 387
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