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  • 351. Berre, I.
    et al.
    Boon, Wietse M.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Flemisch, B.
    Fumagalli, A.
    Gläser, D.
    Keilegavlen, E.
    Scotti, A.
    Stefansson, I.
    Tatomir, A.
    Brenner, K.
    Burbulla, S.
    Devloo, P.
    Duran, O.
    Favino, M.
    Hennicker, J.
    Lee, I. -H
    Lipnikov, K.
    Masson, R.
    Mosthaf, K.
    Nestola, M. G. C.
    Ni, C. -F
    Nikitin, K.
    Schädle, P.
    Svyatskiy, D.
    Yanbarisov, R.
    Zulian, P.
    Verification benchmarks for single-phase flow in three-dimensional fractured porous media2021In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 147, article id 103759Article in journal (Refereed)
    Abstract [en]

    Flow in fractured porous media occurs in the earth's subsurface, in biological tissues, and in man-made materials. Fractures have a dominating influence on flow processes, and the last decade has seen an extensive development of models and numerical methods that explicitly account for their presence. To support these developments, four benchmark cases for single-phase flow in three-dimensional fractured porous media are presented. The cases are specifically designed to test the methods’ capabilities in handling various complexities common to the geometrical structures of fracture networks. Based on an open call for participation, results obtained with 17 numerical methods were collected. This paper presents the underlying mathematical model, an overview of the features of the participating numerical methods, and their performance in solving the benchmark cases.

  • 352.
    Berre, Inga
    et al.
    Univ Bergen, Dept Math, Allegaten 41, N-5007 Bergen, Norway..
    Boon, Wietse M.
    KTH Royal Inst Technol, Dept Math, Lindstedtsvagen 25, S-11428 Stockholm, Sweden..
    Flemisch, Bernd
    Univ Stuttgart, Dept Hydromech & Modelling Hydrosyst, Pfaffenwaldring 61, D-70569 Stuttgart, Germany..
    Fumagalli, Alessio
    Univ Bergen, Dept Math, Allegaten 41, N-5007 Bergen, Norway.;Politecn Milan, Lab Modeling & Sci Comp, Pza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Glaeser, Dennis
    Univ Stuttgart, Dept Hydromech & Modelling Hydrosyst, Pfaffenwaldring 61, D-70569 Stuttgart, Germany..
    Keilegavlen, Eirik
    Univ Bergen, Dept Math, Allegaten 41, N-5007 Bergen, Norway..
    Scotti, Anna
    Politecn Milan, Lab Modeling & Sci Comp, Pza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Stefansson, Ivar
    Univ Bergen, Dept Math, Allegaten 41, N-5007 Bergen, Norway..
    Tatomir, Alexandru
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Gottingen, Dept Appl Geol, Geosci Ctr, Goldschmidtstr 3, D-3707 Gottingen, Germany.;Uppsala Univ, Dept Earth Sci, Villavagen 16, S-75236 Uppsala, Sweden..
    Brenner, Konstantin
    Univ Cote dAzar, CNRS, INRIA, LJAD, Nice, France..
    Burbulla, Samuel
    Univ Stuttgart, Inst Appl Anal & Numer Simulat, Pfaffenwaldring 57, D-70569 Stuttgart, Germany..
    Devloo, Philippe
    FEC Univ Estadual Campinas, R Josiah Willard Gibbs 85 Cidade Univ, BR-13083839 Campinas, SP, Brazil..
    Duran, Omar
    FEC Univ Estadual Campinas, R Josiah Willard Gibbs 85 Cidade Univ, BR-13083839 Campinas, SP, Brazil..
    Favino, Marco
    Univ Lausanne, Inst Earth Sci, UNIL Mouline, Bldg Geopolis, CH-1015 Lausanne, Switzerland..
    Hennicker, Julian
    Univ Genave, Sect Math, 2-4 Rue Liavre,CP 64, CH-1211 Genave, Switzerland..
    Lee, I-Hsien
    Natl Cent Univ, Grad Inst Appl Geol, Taipei, Taiwan.;Natl Cent Univ, Ctr Environm Studies, Taipei, Taiwan..
    Lipnikov, Konstantin
    Los Alamos Natl Lab, Los Alamos, NM USA..
    Masson, Roland
    Univ Cote dAzar, CNRS, INRIA, LJAD, Nice, France..
    Mosthaf, Klaus
    Tech Univ Denmark, Dept Environm Engn, Bldg 115, DK-2800 Lyngby, Denmark..
    Nestola, Maria Giuseppina Chiara
    Univ Svizzera Italiana, Inst Computat Sci, Med & Engn Grp, Numer Simulat Sci, Via G Buffi 13, CH-6900 Lugano Ticino, Switzerland..
    Ni, Chuen-Fa
    Natl Cent Univ, Grad Inst Appl Geol, Taipei, Taiwan.;Natl Cent Univ, Ctr Environm Studies, Taipei, Taiwan..
    Nikitin, Kirill
    Russian Acad Sci, Marchuk Inst Numer Math, Moscow, Russia..
    Schadle, Philipp
    Swiss Fed Inst Technol, Inst Geophys, Geothermal Energy & Geofluids Grp, CH-8092 Zurich, Switzerland..
    Svyatskiy, Daniil
    Los Alamos Natl Lab, Los Alamos, NM USA..
    Yanbarisov, Ruslan
    Russian Acad Sci, Marchuk Inst Numer Math, Moscow, Russia..
    Zulian, Patrick
    Univ Svizzera Italiana, Inst Computat Sci, Med & Engn Grp, Numer Simulat Sci, Via G Buffi 13, CH-6900 Lugano Ticino, Switzerland..
    Verification benchmarks for single-phase flow in three-dimensional fractured porous media2021In: Advances in Water Resources, ISSN 0309-1708, E-ISSN 1872-9657, Vol. 147, article id 103759Article in journal (Refereed)
    Abstract [en]

    Flow in fractured porous media occurs in the earth's subsurface, in biological tissues, and in man-made materials. Fractures have a dominating influence on flow processes, and the last decade has seen an extensive development of models and numerical methods that explicitly account for their presence. To support these developments, four benchmark cases for single-phase flow in three-dimensional fractured porous media are presented. The cases are specifically designed to test the methods' capabilities in handling various complexities common to the geometrical structures of fracture networks. Based on an open call for participation, results obtained with 17 numerical methods were collected. This paper presents the underlying mathematical model, an overview of the features of the participating numerical methods, and their performance in solving the benchmark cases.

  • 353.
    Bertini, Claudia
    et al.
    Univ Roma La Sapienza, Dipartimento Ingn Civile Edile & Ambientale, I-00184 Rome, Italy.
    Buonora, Luca
    Univ Roma La Sapienza, Dipartimento Ingn Civile Edile & Ambientale, I-00184 Rome, Italy.
    Ridolfi, Elena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Ctr Nat Hazards & Disaster Sci, S-75236 Uppsala, Sweden.
    Russo, Fabio
    Univ Roma La Sapienza, Dipartimento Ingn Civile Edile & Ambientale, I-00184 Rome, Italy.
    Napolitano, Francesco
    Univ Roma La Sapienza, Dipartimento Ingn Civile Edile & Ambientale, I-00184 Rome, Italy.
    On the Use of Satellite Rainfall Data to Design a Dam in an Ungauged Site2020In: Water, E-ISSN 2073-4441, Vol. 12, no 11, article id 3028Article in journal (Refereed)
    Abstract [en]

    The estimation of the design peak discharge is crucial for the hydrological design of hydraulic structures. A commonly used approach is to estimate the design storm through the intensity-duration-area-frequency (IDAF) curves and then use it to generate the design discharge through a hydrological model. In ungauged areas, IDAF curves and design discharges are derived throughout regionalization studies, if any exist for the area of interest, or from using the hydrological information of the closest and most similar gauged place. However, many regions around the globe remain ungauged or are very poorly gauged. In this regard, a unique opportunity is provided by satellite precipitation products developed and improved in the last decades. In this paper, we show weaknesses and potentials of satellite data and, for the first time, we evaluate their applicability for design purposes. We employ CMORPH-Climate Prediction Center MORPHing technique satellite precipitation estimates to build IDAF curves and derive the design peak discharges for the Pietrarossa dam catchment in southern Italy. Results are compared with the corresponding one provided by a regionalization study, i.e., VAPI-VAlutazione delle Piene in Italia project, usually used in Italy in ungauged areas. Results show that CMORPH performed well for the estimation of low duration and small return periods storm events, while for high return period storms, further research is still needed.

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  • 354.
    Bertini, Claudia
    et al.
    Sapienza Univ Roma, DICEA, Dipartimento Ingn Civile Edile & Ambienlale, Rome, Italy..
    Ridolfi, Elena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Alfonso, Leonardo
    IHE Delft, Dept Integrated Water Syst & Governance, Inst Water Educ, Hydroinformat Chair, Delft, Netherlands..
    Napolitano, Francesco
    Sapienza Univ Roma, DICEA, Dipartimento Ingn Civile Edile & Ambienlale, Rome, Italy..
    Optima Rain Gauge Network Design Based On Multi-Objective Optimization Approach2020In: International conference on numerical analysis and applied mathematics ICNAAM 2019 / [ed] Simos, T; Tsitouras, C, AIP Publishing , 2020, article id 250002Conference paper (Refereed)
    Abstract [en]

    Precipitation is a main input to many hydrological applications, such as water management, flood forecasting and hydrological modelling. The goodness of the rainfall field estimation can thus affect their performances. Despite radar-based and satellite-based measurements have nowadays become very common and accurate, rain gauges monitoring stations are still needed. The gauge density and its spatial distribution are two of the key factors influencing the accuracy in precipitation estimation. Even if in the last decades many studies proposed several methodologies for the design of optimal monitoring networks, only few studies use hydrological model performance as a design criterion. The purpose of this study is to define the optimal rain gauge network for the Mignone River catchment (Italy). The optimal network is defined through a multi-objective optimization approach, where the interpolation error of precipitation is minimised and the performance of a hydrological model based on the Width Function Instantaneous Unit Hydrograph theory is maximised. The optimization is run both without and with constraints, which are based on rainfall patterns. A score to choose the best set of points in the Pareto front is presented. The results suggest that there are preferential areas where sensors locations achieve optimal interpolation error and model performance.

  • 355.
    Bertini, Claudia
    et al.
    Univ Roma La Sapienza, Dept Civil Construct & Environm Engn, Via Eudossiana 18, I-00184 Rome, Italy..
    Ridolfi, Elena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. CNDS, Ctr Nat Hazards & Disaster Sci, S-75236 Uppsala, Sweden.;Univ Fed Minas Gerais, Belo Horizonte, MG, Brazil..
    Resende de Padua, Luiz Henrique
    Univ Fed Minas Gerais, Belo Horizonte, MG, Brazil..
    Russo, Fabio
    Univ Roma La Sapienza, Dept Civil Construct & Environm Engn, Via Eudossiana 18, I-00184 Rome, Italy..
    Napolitano, Francesco
    Univ Roma La Sapienza, Dept Civil Construct & Environm Engn, Via Eudossiana 18, I-00184 Rome, Italy..
    Alfonso, Leonardo
    IHE Delft Inst Water Educ, Delft, Netherlands..
    An entropy-based approach for the optimization of rain gauge network using satellite and ground-based data2021In: Hydrology Research, ISSN 1998-9563, E-ISSN 2224-7955, Vol. 52, no 3, p. 620-635Article in journal (Refereed)
    Abstract [en]

    Accurate and precise rainfall records are crucial for hydrological applications and water resources management. The accuracy and continuity of ground-based time series rely on the density and distribution of rain gauges over territories. In the context of a decline of rain gauge distribution, how to optimize and design optimal networks is still an unsolved issue. In this work, we present a method to optimize a ground-based rainfall network using satellite-based observations, maximizing the information content of the network. We combine Climate Prediction Center MORPhing technique (CMORPH) observations at ungauged locations with an existing rain gauge network in the Rio das Velhas catchment, in Brazil. We use a greedy ranking algorithm to rank the potential locations to place new sensors, based on their contribution to the joint entropy of the network. Results show that the most informative locations in the catchment correspond to those areas with the highest rainfall variability and that satellite observations can be successfully employed to optimize rainfall monitoring networks.

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  • 356. Bertola, Miriam
    et al.
    Bloeschl, Guenter
    Bohac, Milon
    Borga, Marco
    Castellarin, Attilio
    Chirico, Giovanni B.
    Claps, Pierluigi
    Dallan, Eleonora
    Danilovich, Irina
    Ganora, Daniele
    Gorbachova, Liudmyla
    Ledvinka, Ondrej
    Mavrova-Guirguinova, Maria
    Montanari, Alberto
    Ovcharuk, Valeriya
    Viglione, Alberto
    Volpi, Elena
    Arheimer, Berit
    SMHI, Research Department, Hydrology.
    Aronica, Giuseppe Tito
    Bonacci, Ognjen
    Canjevac, Ivan
    Csik, Andras
    Frolova, Natalia
    Gnandt, Boglarka
    Gribovszki, Zoltan
    Guel, Ali
    Guenther, Knut
    Guse, Bjoern
    Hannaford, Jamie
    Harrigan, Shaun
    Kireeva, Maria
    Kohnova, Silvia
    Komma, Juergen
    Kriauciuniene, Jurate
    Kronvang, Brian
    Lawrence, Deborah
    Luedtke, Stefan
    Mediero, Luis
    Merz, Bruno
    Molnar, Peter
    Murphy, Conor
    Oskorus, Dijana
    Osuch, Marzena
    Parajka, Juraj
    Pfister, Laurent
    Radevski, Ivan
    Sauquet, Eric
    Schroeter, Kai
    Sraj, Mojca
    Szolgay, Jan
    Turner, Stephen
    Valent, Peter
    Veijalainen, Noora
    Ward, Philip J.
    Willems, Patrick
    Zivkovic, Nenad
    Megafloods in Europe can be anticipated from observations in hydrologically similar catchments2023In: Nature Geoscience, ISSN 1752-0894, E-ISSN 1752-0908Article in journal (Refereed)
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    Megafloods in Europe can be anticipated from observations in hydrologically similar catchments
  • 357.
    Bettoni, Laura Nina
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Some Like It Hot: Pre-heating Prior to Bioreactor Treatment Enhances Nitrogen Removal From Mine Drainage2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ammonium-nitrate based explosives (NH4NO3) used within the operations of Kiruna iron ore mine release nitrate (NO3-) into the environment, potentially having adverse effects on local river-systems. One way of reducing NO3- impacts to the environment is through a woodchip denitrifying bioreactor (DBR). Waste rock leachate is collected and passed through the bioreactor, where denitrifying microbial communities reduce NO3- to nitrogen gas (N2) using a carbon energy source. However, the efficiency of the DBR present in Kiruna iron ore mine has declined since the start of its operation leading to lower values of NO3-removal throughout the years. 

    Denitrification being a temperature dependent process, a heating device was installed to warm up the water prior to the DBR treatment to counterbalance this decrease. The effect of which has been assessed within this thesis. Chemical analyses encompassing NO3-, nitrite (NO2-), ammonium (NH4+), total organic carbon (TOC), phosphorus compounds (tot-P, PO4-P), and bacterial abundance were then investigated along a flowpath in the DBR. Overall, the results have shown that with an increase in temperature prior to the treatment, TOC, tot-P, PO4-P release was improved. Moreover, NO3- removal doubled compared to the previous year. TOC, tot-P and PO4-P are the result of the hydrolysis process, transforming the woodchips in available carbon source and providing nutrients for the bacteria to perform denitrification. Similarly, the bacterial abundance presented a significant increase with temperature. This suggest that both hydrolysis and bacteria growth enhancement with temperature ultimately participated in the improvement of the denitrification reaction. Moreover, a long-lasting effect of temperature on NO3- removal was observed during a following cold period as NO3- removal stayed above 45% after two months without heating. It is suggested that the cost of heating can be reduced by inducing “heat pulse” instead of continuous heating. Adding a heating system prior to treatment represents a promising solution for the future of sustainable mining, particularly for mines located in extreme climates such as Kiruna. 

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  • 358.
    Beven, Keith
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Lancaster, Lancaster Environm Ctr, Lancaster, England..
    Advice to a young hydrologist2016In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 30, no 20, p. 3578-3582Article in journal (Other academic)
  • 359.
    Beven, Keith
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Lancaster, Lancaster Environm Ctr, Lancaster, England..
    Facets of uncertainty: epistemic uncertainty, non-stationarity, likelihood, hypothesis testing, and communication2016In: Hydrological Sciences Journal, ISSN 0262-6667, E-ISSN 2150-3435, Vol. 61, no 9, p. 1652-1665Article in journal (Refereed)
    Abstract [en]

    This paper presents a discussion of some of the issues associated with the multiple sources of uncertainty and non-stationarity in the analysis and modelling of hydrological systems. Different forms of aleatory, epistemic, semantic, and ontological uncertainty are defined. The potential for epistemic uncertainties to induce disinformation in calibration data and arbitrary non-stationarities in model error characteristics, and surprises in predicting the future, are discussed in the context of other forms of non-stationarity. It is suggested that a condition tree is used to be explicit about the assumptions that underlie any assessment of uncertainty. This also provides an audit trail for providing evidence to decision makers.

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  • 360.
    Beven, Keith
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    So how much of your error is epistemic? Lessons from Japan and Italy2013In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 27, no 11, p. 1677-1680Article in journal (Other academic)
  • 361.
    Beven, Keith
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Lancaster Environment Centre, Lancaster University, Lancaster, UK.
    Almeida, Susana
    Univ Bristol, Dept Civil Engn, Bristol, Avon, England.
    Aspinall, Willy P.
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Bates, Paul D.
    Univ Bristol, Sch Geog Sci, Bristol, Avon, England.
    Blazkova, Sarka
    TG Masaryk Water Resource Inst, Prague, Czech Republic.
    Borgomeo, Edoardo
    Univ Oxford, Environm Change Inst, Oxford, England.
    Freer, Jim
    Univ Bristol, Sch Geog Sci, Bristol, Avon, England.
    Goda, Katsuichiro
    Univ Bristol, Dept Civil Engn, Bristol, Avon, England.
    Hall, Jimw.
    Univ Oxford, Environm Change Inst, Oxford, England.
    Phillips, Jeremy C.
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Simpson, Michael
    Univ Oxford, Environm Change Inst, Oxford, England.
    Smith, Paul J.
    Univ Lancaster, Lancaster Environm Ctr, Lancaster, England;Waternumbers Ltd, Halton Mill, Lancaster LA2 6DN, England.
    Stephenson, David B.
    Univ Exeter, Dept Math & Comp Sci, Exeter, Devon, England.
    Wagener, Thorsten
    Univ Bristol, Dept Civil Engn, Bristol, Avon, England;Univ Bristol, Cabot Inst, Bristol, Avon, England.
    Watson, Matt
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Wilkins, Kate L.
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Epistemic uncertainties and natural hazard risk assessment - Part 1: A review of different natural hazard areas2018In: Natural hazards and earth system sciences, ISSN 1561-8633, E-ISSN 1684-9981, Vol. 18, no 10, p. 2741-2768Article, review/survey (Refereed)
    Abstract [en]

    This paper discusses how epistemic uncertainties are currently considered in the most widely occurring natural hazard areas, including floods, landslides and debris flows, dam safety, droughts, earthquakes, tsunamis, volcanic ash clouds and pyroclastic flows, and wind storms. Our aim is to provide an overview of the types of epistemic uncertainty in the analysis of these natural hazards and to discuss how they have been treated so far to bring out some commonalities and differences. The breadth of our study makes it difficult to go into great detail on each aspect covered here; hence the focus lies on providing an overview and on citing key literature. We find that in current probabilistic approaches to the problem, uncertainties are all too often treated as if, at some fundamental level, they are aleatory in nature. This can be a tempting choice when knowledge of more complex structures is difficult to determine but not acknowledging the epistemic nature of many sources of uncertainty will compromise any risk analysis. We do not imply that probabilistic uncertainty estimation necessarily ignores the epistemic nature of uncertainties in natural hazards; expert elicitation for example can be set within a probabilistic framework to do just that. However, we suggest that the use of simple aleatory distributional models, common in current practice, will underestimate the potential variability in assessing hazards, consequences, and risks. A commonality across all approaches is that every analysis is necessarily conditional on the assumptions made about the nature of the sources of epistemic uncertainty. It is therefore important to record the assumptions made and to evaluate their impact on the uncertainty estimate. Additional guidelines for good practice based on this review are suggested in the companion paper (Part 2).

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  • 362.
    Beven, Keith
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Lancaster, Lancaster Environm Ctr, Lancaster, England.
    Aspinall, Willy P.
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Bates, Paul D.
    Univ Bristol, Sch Geog Sci, Bristol, Avon, England.
    Borgomeo, Edoardo
    Univ Oxford, Environm Change Inst, Oxford, England.
    Goda, Katsuichiro
    Univ Bristol, Dept Civil Engn, Bristol, Avon, England.
    Hall, Jim W.
    Univ Oxford, Environm Change Inst, Oxford, England.
    Page, Trevor
    Univ Lancaster, Lancaster Environm Ctr, Lancaster, England.
    Phillips, Jeremy C.
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Simpson, Michael
    Univ Oxford, Environm Change Inst, Oxford, England.
    Smith, Paul J.
    Univ Lancaster, Lancaster Environm Ctr, Lancaster, England;European Ctr Medium Range Weather Forecasting, Reading, Berks, England.
    Wagener, Thorsten
    Univ Bristol, Dept Civil Engn, Bristol, Avon, England;Univ Bristol, Cabot Inst, Bristol, Avon, England.
    Watson, Matt
    Univ Bristol, Sch Earth Sci, Bristol, Avon, England.
    Epistemic uncertainties and natural hazard risk assessment - Part 2: What should constitute good practice?2018In: Natural hazards and earth system sciences, ISSN 1561-8633, E-ISSN 1684-9981, Vol. 18, no 10, p. 2769-2783Article in journal (Refereed)
    Abstract [en]

    Part 1 of this paper has discussed the uncertainties arising from gaps in knowledge or limited understanding of the processes involved in different natural hazard areas. Such deficits may include uncertainties about frequencies, process representations, parameters, present and future boundary conditions, consequences and impacts, and the meaning of observations in evaluating simulation models. These are the epistemic uncertainties that can be difficult to constrain, especially in terms of event or scenario probabilities, even as elicited probabilities rationalized on the basis of expert judgements. This paper reviews the issues raised by trying to quantify the effects of epistemic uncertainties. Such scientific uncertainties might have significant influence on decisions made, say, for risk management, so it is important to examine the sensitivity of such decisions to different feasible sets of assumptions, to communicate the meaning of associated uncertainty estimates, and to provide an audit trail for the analysis. A conceptual framework for good practice in dealing with epistemic uncertainties is outlined and the implications of applying the principles to natural hazard assessments are discussed. Six stages are recognized, with recommendations at each stage as follows: (1) framing the analysis, preferably with input from potential users; (2) evaluating the available data for epistemic uncertainties, especially when they might lead to inconsistencies; (3) eliciting information on sources of uncertainty from experts; (4) defining a workflow that will give reliable and accurate results; (5) assessing robustness to uncertainty, including the impact on any decisions that are dependent on the analysis; and (6) communicating the findings and meaning of the analysis to potential users, stakeholders, and decision makers. Visualizations are helpful in conveying the nature of the uncertainty outputs, while recognizing that the deeper epistemic uncertainties might not be readily amenable to visualizations.

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  • 363.
    Beven, Keith
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Cloke, Hannah L.
    Department of Geography, King's College London, London, UK.
    Comment on ‘‘Hyperresolution global land surface modeling: Meeting a grand challenge for monitoring Earth’s terrestrial water’’ by Eric F. Wood et al.2012In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 48, p. W01801-Article in journal (Refereed)
  • 364.
    Beven, Keith
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Univ Lancaster, Lancaster Environm Ctr, Lancaster LA1 4YQ, England.;Univ Lausanne, IDYST, Lausanne, Switzerland..
    Davies, Jess
    Univ Lancaster, Lancaster Environm Ctr, Lancaster LA1 4YQ, England..
    Velocities, celerities and the basin of attraction in catchment response2015In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 29, no 25, p. 5214-5226Article in journal (Refereed)
    Abstract [en]

    Catchment systems are interestingly nonlinear, but their dynamics are constrained from being unduly chaotic by mass and energy balance requirements. There have been no attempts in hydrology that we know of that have tried to map both the flow and transport dynamics of a catchment in any form of phase space. In part, this is because of the high dimensionality of the space-time patterns of response; in part because there is sufficient uncertainty about the input and output fluxes estimated by measurement that this might be expected to obscure any attractor-like behaviour. In this study we explore the basin of the catchment attractor for the Multiple Interacting Pathway (MIPs) model that in previous papers has been shown to give good results for the small Gardsjon catchment in Sweden. MIPs is based on particle tracking techniques and gives results for both the flow responses and for the travel and residence time responses of water in the catchment. Here it is used to provide consistent values of fluxes, total storage, travel time distributions and residence time distributions for a long simulation period. The nature of those responses in storage and input dimensions is then investigated. The results suggest that the range of behaviours is hysteretic in interesting ways and constrained by the forcing inputs, with space filling of trajectories in the basin of attraction as should be expected of a forced dissipative system. The range of behaviours exhibited defines a space that the responses of any simpler emulator model will need to span.

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  • 365.
    Beven, Keith J
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Comment on “Equifinality of formal (DREAM) and informal (GLUE) Bayesian approaches in hydrologic modeling?” by Jasper A. Vrugt, Cajo J. F. ter Braak, Hoshin V. Gupta and Bruce A. Robinson2009In: Stochastic environmental research and risk assessment (Print), ISSN 1436-3240, E-ISSN 1436-3259, Vol. 23, p. 1059-1060Article in journal (Refereed)
  • 366. Beven, Keith J.
    Uncertainty in Predictions of Floods and Hydraulic Transport2007In: Transport phenomena in hydraulics / [ed] Rowiński, Paweł, Warszawa: Institute of Geophysics , 2007, p. 5-20Chapter in book (Other academic)
    Abstract [en]

    This paper provides a review of work within the Generalised Likelihood Uncertainty Estimation (GLUE) methodology on estimating uncertainties in predicting flood frequency, flood inundation, and hydraulic transport of solutes in rivers and soils. The issue of prediction uncertainty as an input decision making is also discussed. It is concluded that in real applications it is unlikely that a fully objective approach to uncertainty estimation is possible. It is therefore important that the assumptions made are stated explicitly so that they can be agreed or disputed with the users of the resulting predictions. It is also important that the modelling process be considered as a learning process of constraining uncertainty by adding new information.

  • 367.
    Beygi, Heydar
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Impact of irrigation development and climate change on the water level of Lake Urmia, Iran2015Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Lake Urmia, located in the north-west of Iran, is one of the largest hypersaline lakes in the world. In recent years, there has been a significant decrease in the lake’s area and volume by 88% and 80% respectively. An integrated water balance model of the Lake Urmia Drainage Basin (LUDB) and Lake Urmia was developed to identify these main drivers of the significant changes, and to investigate the possible future evolution of the lake under effects of projected climate change and land use change. We used an energy balance method to estimate the evaporation from the lake and the Turc-Langbein method to estimate the evapotranspiration from the drainage basin of the lake. Agricultural irrigation water was introduced to the model as an extra precipitation over the irrigated fields, after being subtracted from the surplus runoff (precipitation−evapotranspiration). The agricultural land development was assumed to be linear that changed from 300000 ha at 1979 to 500000 at 2010, which is consistent with the best available data on the actual irrigation development in the basin. We estimated the annual evaporation over the Lake Urmia and the evapotranspiration over its drainage basin as 932 mm and 287 mm respectively. Our results showed that decreased precipitation and increased temperature over the basin since 1995 could explain 68% of the observed lake level decrease. Irrigation developments during the last four decades were found to be responsible for 32% of the observed lake level decrease. Thus the future lake level of the Lake Urmia is very likely to continue to decrease unless the current climate condition will be followed by a period of increased precipitation. If the current climate conditions will prevail also in the future, even a 20% decrease in the irrigated land area, which is actually quite ambitious, will not make the lake recover to its ecological level at the end of 2020.

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  • 368. Bhattacharya, B.
    et al.
    Mazzoleni, Maurizio
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Ugay, R.
    Flood inundation mapping of the sparsely gauged large-scale Brahmaputra basin using remote sensing products2019In: Remote Sensing, Vol. 11, no 5, article id 501Article in journal (Refereed)
  • 369.
    Bhattacharya, P.
    et al.
    ivision of Land and Water Resources, Kungliga Tekniska Högskolan, SE-100 44 Stockholm, SwedenSE.
    Jacks, G.
    ivision of Land and Water Resources, Kungliga Tekniska Högskolan, SE-100 44 Stockholm, SwedenSE.
    Ahmed, K. M.
    ivision of Land and Water Resources, Kungliga Tekniska Högskolan, SE-100 44 Stockholm, SwedenSE.
    Routh, Joyanto
    Biogeochemistry Section, Department of Geology and Geochemistry, Stockholm University, SE-106 91 Stockholm, SwedenSE.
    Khan, A. A.
    Department of Geology, University of Dhaka, Dhaka 1000, Bangladesh.
    Arsenic in Groundwater of the Bengal Delta Plain Aquifers in Bangladesh2002In: Bulletin of Environmental Contamination and Toxicology, ISSN 0007-4861, E-ISSN 1432-0800, Vol. 69, no 4, p. 538-545Article in journal (Refereed)
    Abstract [en]

    Not Available

  • 370.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, K.M.
    Hasan, M.A.
    Broms, S.
    Fogelström, J.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sracek, O.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Routh, J.
    Mobility of arsenic in groundwater in a part of Brahmanbaria district, NE Bangladesh2006In: Managing Arsenic in the Environment: From soil to human health / [ed] Naidu, R., Smith, E., Owens, G., Bhattacharya, P. Nadebaum. P., Melbourne, Australia: CSIRO Publishing , 2006, p. 95-115Chapter in book (Refereed)
  • 371.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Claesson, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Fagerberg, Jens
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bundschuh, Jochen
    Storniolo, Angel del R.
    Martin, Raul A.
    Thir, Juan Martin
    Sracek, Ondra
    Natural arsenic in the groundwater of the alluvial aquifers of Santiago del Estero Province, Argentina2005In: Natural Arsenic in Groundwater: Occurrence, Remediation and Management / [ed] Bundschuh, J; Bhattacharya, P; Chandrasekharam, D, London: Balkema, 2005, p. 57-65Conference paper (Refereed)
    Abstract [en]

    Natural occurrences of arsenic has been documented in groundwater of the shallow aquifers of the Chaco-Pampean Plain, Argentina. The distribution of arsenic and mechanisms of its mobilization in the shallow alluvial aquifers was investigated around the city of Santiago del Estero in Northwestern Argentina in order to provide an insight into the complex hydrological and geochemical conditions that yields high As concentrations in groundwater. Significant spatial variations of total arsenic (As-tot) concentrations were observed with an average value of 743 mu g/L. Arsenate was a dominant species in most samples. Average concentrations of Al, Mn, and Fe were 360 mu g/L, 574 mu g/L, and 459 mu g/L, respectively. The 7M HNO3 extraction of sediments and volcanic ash-layer indicated AS(N03) concentrations ranging between 2.5-7.1 mg/kg. AS(N03) indicated a significant positive correlation with Mn-N03, Al-N03, and Fe-N03. Oxalate extractions revealed significant fractions of As (Aso(ox)) in the sediments (0.4-1.4mg/kg) and a dominance of oxalate extractable Al- and Mn. Speciation calculations indicate that Al oxide and hydroxides have the potential to precipitate in the groundwater, suggesting that As adsorption processes may be to some extent controlled by Al oxides and hydroxides. Mobility of As at local scale seems to depend on high pH values, related to the dissolution of carbonates driven by cation exchange, and dissolution of silicates. There is a clear relationship of As with F, V, B and Si, suggesting their common origin in volcanic ash layer. Preliminary conceptual model of arsenic input includes release of As and Al from dissolution of volcanic ash layer, precipitation of Al oxides and hydroxides followed by adsorption of As on Al and Fe phases in sediments, and release of As under high pH conditions.

  • 372.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Mukherjee, A.
    Mukherjee, A. B.
    Groundwater Arsenic in India: Source, Distribution, Effects and Alternate Safe Drinking Water Sources2013In: Reference Module in Earth Systems and Environmental Sciences, Elsevier, 2013Chapter in book (Other academic)
    Abstract [en]

    Elevated natural groundwater arsenic, a carcinogen, has created a severe environmental health crisis in several parts of India. Since the discovery of groundwater arsenic and arsenicosis in West Bengal, in 1984, a huge wealth of information has been generated by groundwater arsenic research during the last three decades. The principal mechanism of arsenic mobilization in groundwater is believed to be reductive dissolution of Fe-oxyhydroxides in aquifer sediments. Arsenic enriched groundwater used for irrigation also leads to long-term risks for arsenic enrichment in the soils and bioaccumulation in crops. Various studies are ongoing to develop a holistic approach for arsenic mitigation.

  • 373.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, M.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Hasan, M.A.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, K.M.
    Sracek, O.
    Jakariya, M.
    Huq, S.M.I.
    Naidu, R.
    Smith, E.
    Owens, G.
    Arsenic mobilisation in the Holocene flood plains in South-central Bangladesh: Evidences from the hydrogeochemical trends and modeling results2008In: Groundwater for Sustainable Development: Problems, Perspectives and Challenges / [ed] Bhattacharya, P., Ramanathan, AL., Mukherjee A.B., Bundschuh, J., Chandrasekharam, D. Keshari, A.K., The Netherlands: Taylor and Francis/A.A. Balkema , 2008, p. 283-299Chapter in book (Refereed)
  • 374.
    Bidleman, Terry
    et al.
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Andersson, Agneta
    Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden, Umeå Marine Sciences Centre, Hörnefors, Sweden.
    Jantunen, Liisa
    Centre for Atmospheric Research Experiments, Environment and Climate Change Canada, Canada.
    Kucklick, John
    Chemical Sciences Division, National Institute of Standards and Technology, Hollings Marine Laboratory, Charleston, SC, USA.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences. Research Unit: Environmental Sciences and Management, North–West University, Potchefstroom, South Africa.
    Letcher, Robert
    Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, Canada.
    Tysklind, Mats
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Wong, Fiona
    Air Quality Processes Research Section, Environment and Climate Change Canada, Toronto, Canada.
    A review of halogenated natural products in Arctic, Subarctic and Nordic ecosystems2019In: Emerging Contaminants, ISSN 2405-6650, E-ISSN 2405-6642, Vol. 5, p. 89-115Article in journal (Refereed)
    Abstract [en]

    Halogenated natural products (HNPs) are organic compounds containing bromine, chlorine, iodine, andrarely fluorine. HNPs comprise many classes of compounds, ranging in complexity from halocarbons tohigher molecular weight compounds, which often contain oxygen and/or nitrogen atoms in addition tohalogens. Many HNPs are biosynthesized by marine bacteria, macroalgae, phytoplankton, tunicates,corals, worms, sponges and other invertebrates. This paper reviews HNPs in Arctic, Subarctic and Nordicecosystems and is based on sections of Chapter 2.16 in the Arctic Monitoring and Assessment Program(AMAP) assessment Chemicals of Emerging Arctic Concern (AMAP, 2017) which deal with the highermolecular weight HNPs. Material is updated and expanded to include more Nordic examples. Much ofthe chapter is devoted to “bromophenolic” HNPs, viz bromophenols (BPs) and transformation productsbromoanisoles (BAs), hydroxylated and methoxylated bromodiphenyl ethers (OH-BDEs, MeO-BDEs) andpolybrominated dibenzo-p-dioxins (PBDDs), since these HNPs are most frequently reported. Othersdiscussed are 2,20-dimethoxy-3,30,5,50-tetrabromobiphenyl (2,20-dimethoxy-BB80), polyhalogenated 10-methyl-1,20-bipyrroles (PMBPs), polyhalogenated 1,10-dimethyl-2,20-bipyrroles (PDBPs), polyhalogenatedN-methylpyrroles (PMPs), polyhalogenated N-methylindoles (PMIs), bromoheptyl- and bromooctylpyrroles, (1R,2S,4R,5R,10E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(20-chloroethenyl)-5-methylcyclohexane (mixed halogenated compound MHC-1), polybrominated hexahydroxanthene derivatives(PBHDs) and polyhalogenated carbazoles (PHCs). Aspects of HNPs covered are physicochemicalproperties, sources and production, transformation processes, concentrations and trends in the physicalenvironment and biota (marine and freshwater). Toxic properties of some HNPs and a discussion of howclimate change might affect HNPs production and distribution are also included. The review concludeswith a summary of research needs to better understand the role of HNPs as “chemicals of emergingArctic concern”.

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  • 375.
    Bidleman, Terry
    et al.
    Umeå University, Sweden.
    Kucklick, John
    National Oceanic and Atmospheric Administration, USA.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Letcher, Robert
    Environment and Climate Change, Canada.
    Jantunen, Liisa
    Environment and Climate Change, Canada.
    Wong, Fiona
    Environment and Climate Change, Canada.
    Halogenated Natural Products2017In: AMAP Assessment 2016: Chemicals of Emerging Arctic Concern, Oslo, Norway: AMAP - Arctic Monitoring and Assessment Programme , 2017, p. 243-267Chapter in book (Refereed)
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    Halogenated Natural Products
  • 376.
    Bidleman, Terry
    et al.
    Umeå universitet, Sweden.
    Kucklick, John
    National Institute of Standards and Technology, South Carolina, USA.
    Letcher, Robert
    National Wildlife Research Centre, Canada.
    Jantunen, Liisa
    Environment and Climate Change, Canada.
    Wong, Fiona
    Environment and Climate Change, Canada.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    CONTAMINANTS OF EMERGING CONCERN IN THE ARCTIC: AN ASSESSMENT OF HALOGENATED NATURAL PRODUCTS2016In: Organohalogen Compounds, ISSN 1026-4892, Vol. 78, p. 193-196, article id 8.4010Article in journal (Refereed)
  • 377.
    Bidleman, Terry
    et al.
    Umeå University, Sweden.
    Kurt-Karakus, Perihan
    Bahcesehir University, Istanbul, Turkey.
    Armitage, James
    University of Toronto, Ontario, Canada.
    Brown, Tanya
    University of Victoria, British Columbia, Canada.
    Danon Schaffer, Monica
    University of British Columbia, Vancouver, Canada.
    Helm, Paul
    Ontario Ministry of the Environment, Toronto, Canada.
    Hung, Haley
    Meteorological Services Canada .
    Jantunen, Liisa
    Environment Canada.
    Kylin, Henrik
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Li, Yi-Fan
    Environment, Canada.
    Loock, Daniela
    Royal Military College of Canada.
    Luttmer, Carol
    Royal Military College of Canada.
    Ma, Jianmin
    Lanzhou University, Peoples Republic of China.
    Macdonald, Robie
    Fisheries and Oceans, Canada.
    Mackay, Don
    Trent University, Peterborough, Ontario, Canada.
    Reid, Liisa
    Trent University, Peterborough, Ontario, Canada.
    Reimer, Ken
    Royal Military College of Canada.
    Chapter 2: Properties, sources, global fate and transport2013In: Canadian Arctic Contaminants Assessment Report III 2013: Persistent Organic Pollutants in Canada’ s North / [ed] Derek Muir, Perihan Kurt-Karakus and Peter Stow, Ottawa: Northern Contaminants Program, Aboriginal Affairs and Northern Development Canada , 2013, p. 19-146Chapter in book (Refereed)
    Abstract [en]

    Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a section on “Physicochemical Properties of Persistent Organic Pollutants”, which identified key physicochemical (pchem) properties, provided the rationale for their measurement or prediction and tabulated literature citations for chemicals that are of concern to the NCP (Bidleman et al. 2003). The section also discussed temperature dependence of pchem properties and their applications to describing partitioning in the physical environment.

    There is, and will continue to be, emphasis on predictive approaches to screening chemicals for persistence, bioaccumulation and toxic (PB&T)properties, as well as long-range atmospheric transport (LRAT) potential (Brown and Wania 2008, Czub et al. 2008, Fenner et al. 2005, Gouin andWania 2007, Howard and Muir 2010, Klasmeier et al. 2006, Matthies et al. 2009, Muir and Howard 2006). This has created the need for determining pchem properties of new and emerging chemicals of concern.

    Predicting gas exchange cycles of legacy persistent organic pollutants (POPs) and new and emerging chemicals of concern places a high demand on the accuracy of pchem properties, particularly the air/water partition coefficient, KAW. Hexachlorocyclohexanes (HCHs) in Arctic Ocean surface waters are close to air-water equilibrium, with excursions toward net volatilization or deposition that vary with location and season (Hargrave et al. 1993, Jantunen et al. 2008a, Lohmann et al. 2009, Su et al. 2006, Wong et al. 2011) while hexachlorobenzene (HCB) (Lohmann et al. 2009, Su et al. 2006, Wong et al. 2011) and some current use pesticides (CUPs) (Wong et al. 2011) are undergoing net deposition. The predicted Arctic Contamination Potential (ACP) for persistent organic chemicals is strongly influenced by ice cover due to its effect on air-water gas exchange (Meyer and Wania 2007).

    Many advances have taken place and numerous papers have been published since CACAR-II, which present new measurements and predictions of pchem properties. This section does not attempt to provide a comprehensive review of the field, or to compile pchem properties from the many studies. The approach taken is to highlight the reports which are most relevant to polar science, particularly in areas of improving reliability of pchem properties for POPs, improving experimental techniques and comparing predictive methods. The section ends with a discussion of polyparameter linear free energy relationships (pp-LFERs), which goes beyond partitioning descriptions based on single pchem properties by taking into account specific chemical interactions that can take place in airsurface and water-surface exchange processes. A detailed list of chemical names and nomenclature are provided in the Glossary.

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  • 378.
    Bignert, Anders
    et al.
    Swedish Museum of Natural History, Stockholm, Sweden.
    Bäcklin, Britt-Marie
    Swedish Museum of Natural History, Stockholm, Sweden.
    Helander, Björn
    Swedish Museum of Natural History, Stockholm, Sweden.
    Roos, Anna
    Swedish Museum of Natural History, Stockholm, Sweden.
    9. Contaminants and Health of Aquatic Wildlife2012In: Ecology and Animal Health / [ed] Leif Norrgren and Jeffrey Levengood, Uppsala: Baltic University Press , 2012, 1, p. 73-85Chapter in book (Other (popular science, discussion, etc.))
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    ehsa 2-9
  • 379. Bijmans, Martijn FM
    et al.
    van Helvoort, Pieter-Jan
    Dar, Shabir A
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Dopson, Mark
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Lens, Piet NL
    Buisman, Cees JN
    Selective recovery of nickel over iron from a nickel-iron solution using microbial sulfate reduction in a gas-lift bioreactor2009In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 43, no 3, p. 853-861Article in journal (Refereed)
    Abstract [en]

    Process streams with high concentrations of metals and sulfate are characteristic for the mining and metallurgical industries. This study aims to selectively recover nickel from a nickel-iron-containing solution at pH 5.0 using a single stage bioreactor that simultaneously combines low pH sulfate reduction and metal-sulfide formation. The results show that nickel was selectively precipitated in the bioreactor at pH 5.0 and the precipitates consisted of >= 83% of the nickel content. The nickel-iron precipitates were partly crystalline and had a metal/sulfur ratio of 1, suggesting these precipitates were NiS and FeS. Experiments focusing on nickel recovery at pH 5.0 and 5.5 reached a recovery of >99.9%, resulting in a nickel effluent concentration <0.05 mu M. The mixed microbial population included known sulfate reducers and acetogens. This study shows that selective metal precipitation in a single stage sulfate reducing bioreactor operated at low pH has the potential to produce metal-sulfides that can be used by the metallurgical industry as a resource for metal production.

  • 380.
    Bindler, Richard
    et al.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Klaminder, Jonatan
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Beyond the peat: synthesizing peat, lake sediments and soils in studies of the Swedish environment2006In: Peatlands: basin evolution and depository of records on global environmental and climatic changes / [ed] I.P. Martini, A. Martínez Cortizas and W. Chesworth, Elsevier, 2006, p. 431-448Chapter in book (Other academic)
    Abstract [en]

    This chapter illustrates on comparing peat and lake sediment records and linking the quantitative record of metals in peat to contemporary environmental problems. Quantifying metal records in peat has been an important step, but new research needs to move beyond this and consider how to apply these data. Lead analyses, including stable isotopes, are now fairly routine and based on these analyses the historical trends of lead deposition are now well established in peat, lake sediments and even glacial ice. The biogeochemical cycling of lead has also been well researched, which allows making this link between the historical lead record and soil biogeochemistry. Because peat and lake sediments seem to record the same changes in mercury deposition, there is similar promise in linking the long-term peat record of mercury and other metals with biogeochemical cycling of mercury and other important metals in forests and soils.

  • 381. Birkel, Christian
    et al.
    Dehaspe, Joni
    Chavarria-Palma, Andres
    Venegas-Cordero, Nelson
    Capell, Réne
    SMHI, Research Department, Hydrology.
    Duran-Quesada, Ana Maria
    Projected climate change impacts on tropical life zones in Costa Rica2021In: Progress in physical geography, ISSN 0309-1333, E-ISSN 1477-0296, article id 03091333211047046Article in journal (Refereed)
    Abstract [en]

    Efforts to protect tropical ecosystems aim at implementing biological corridors across the national territory of Costa Rica. However, potential near-future climate change challenges the effectiveness of such conservation measures. For this purpose, we developed near-future climate change scenarios at high spatial resolution using open-access global data from the Copernicus Climate Data Store (CDS). These projections resulted from downscaling (to a 1km(2) national grid) and quantile-mapping bias-correction of the Essential Climate Variables Global Circulation Model (ECV_GCM) ensemble mean from the CDS using a moderate Representative Concentration Pathway 4.5 (RCP4.5). Projections were evaluated with limited local station data and applied to generate future ecosystem indicators (Holdridge Life Zones, HLZs). We show significantly increasing temperatures of 2.6 degrees C with a spatial variability of +/- 0.4 degrees C for Costa Rica until 2040 with local differences (higher temperatures projected for the southern Costa Rican Caribbean). The future mean annual precipitation showed slightly wetter conditions (120 +/- 43 mm/year) and most prominently in the Costa Rican Caribbean and south Pacific, but no significant drying in the north of Costa Rica by 2040. The bias-corrected climate data were aggregated to decadal and 30-year average (1971-2040) life zone ecosystem indicators that could potentially show ecosystem shifts. Changes in the life zones are most likely due to warmer temperatures and to a lesser extent caused by projected wetter conditions. Shifts are more likely to occur at higher elevations with a potential loss of the sub-tropical rainforest ecosystem. The projections support diminishing tropical dry forests and slightly increasing tropical rain and wet forests in the biological corridors of the driest and wettest regions, respectively. A countrywide spatial uniformity of dominating tropical moist forests (increase from 24% to 49%) at the expense of other HLZs was projected by 2040.

  • 382.
    Biscarini, Chiara
    et al.
    University for Foreigners of Perugia, Perugia, Italy.
    Di Francesco, Silvia
    Niccolò Cusano University, Rome, Italy.
    Ridolfi, Elena
    University of Perugia, Perugia, Italy.
    Manciola, Piergiorgio
    University of Perugia, Perugia, Italy.
    On the simulation of floods in a narrow bending valley: The malpasset dam break case study2016In: Water, Vol. 8, no 11, article id 545Article in journal (Refereed)
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  • 383.
    Bishop, Adrian N.
    et al.
    KTH, School of Computer Science and Communication (CSC), Computer Vision and Active Perception, CVAP.
    Fidan, Baris
    Anderson, Brian D. O.
    Dogancay, Kutluyil
    Pathirana, Pubudu N.
    Optimal Range-Difference-Based Localization Considering Geometrical Constraints2008In: IEEE Journal of Oceanic Engineering, ISSN 0364-9059, E-ISSN 1558-1691, Vol. 33, no 3, p. 289-301Article in journal (Refereed)
    Abstract [en]

    This paper proposes a new type of algorithm aimed at finding the traditional maximum-likelihood (TML) estimate of the position of a target given time-difference-of-arrival (TDOA) information, contaminated by noise. The novelty lies in the fact that a performance index, akin to but not identical with that in maximum likelihood (ML), is a minimized subject to a number of constraints, which flow from geometric constraints inherent in the underlying problem. The minimization is in a higher dimensional space than for TML, and has the advantage that the algorithm can be very straightforwardly and systematically initialized. Simulation evidence shows that failure to converge to a solution of the localization problem near the true value is less likely to occur with this new algorithm than with TML. This makes it attractive to use in adverse geometric situations.

  • 384. Bishop, K.
    et al.
    Seibert, J.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Nyberg, L.
    Rodhe, A.
    Water storage in a till catchment. II: Implications of transmissivity feedback for flow paths and turnover times2011In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 25, no 25, p. 3950-3959Article in journal (Refereed)
    Abstract [en]

    This paper explores the flow paths and turnover times within a catchment characterized by the transmissivity feedback mechanism where there is a strong increase in the saturated hydraulic conductivity towards the soil surface and precipitation inputs saturate progressively more superficial layers of the soil profile. The analysis is facilitated by the correlation between catchment water storage and groundwater levels, which made it possible to model the daily spatial distribution of water storage, both vertically in different soil horizons and horizontally across a 6300-m2 till catchment. Soil properties and episodic precipitation input dynamics, combined with the influence of topographic features, concentrate flow in the horizontal, vertical, and temporal dimensions. Within the soil profile, there was a vertical concentration of lateral flow to superficial soil horizons (upper 30?cm of the soil), where much of the annual flow occurred during runoff episodes. Overland flow from a limited portion of the catchment can contribute to peak flows but is not a necessary condition for runoff episodes. The spatial concentration of flow, and the episodic nature of runoff events, resulted in a strong and spatially structured differentiation of local flow velocities within the catchment. There were large differences in the time spent by the laterally flowing water at different depths, with turnover times of lateral flow across a 1-m-wide soil pedon ranging from under 1?h at 10- to 20-cm depth to a month at 70- to 80-cm depth. In many regards, the hydrology of this catchment appears typical of the hydrology in till soils, which are widespread in Fenno-Scandia. Copyright (c) 2011 John Wiley & Sons, Ltd.

  • 385. Bishop, Kevin
    et al.
    Beven, Keith
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Destouni, Georgia
    Abrahamsson, Katarina
    Andersson, Lotta
    Johnson, K
    Rodhe, Johan
    Hjerdt, Niclas
    Nature as the “Natural” Goal for Water Management: A Conversation2009In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, p. 209-214Article in journal (Refereed)
    Abstract [en]

    The goals for water-quality and ecosystem integrity are often defined relative to “natural” reference conditions in many water-management systems, including the European Union Water Framework Directive. This paper examines the difficulties created for water management by using “natural” as the goal. These difficulties are articulated from different perspectives in an informal (fictional) conversation that takes place after a workshop on reference conditions in water-resources management. The difficulties include defining the natural state and modeling how a system might be progressed toward the natural, as well as the feasibility and desirability of restoring a natural state. The paper also considers the appropriateness for developing countries to adopt the use of natural as the goal for water management. We conclude that failure to critically examine the complexities of having “natural” as the goal will compromise the ability to manage the issues that arise in real basins by not making the ambiguities associated with this “natural” goal explicit. This is unfortunate both for the western world that has embraced this model of “natural as the goal” and for the developing world in so far as they are encouraged to adopt this model.

  • 386.
    Bishop, Kevin
    et al.
    Swedish University Agriculture Science, Sweden.
    Beven, Keith
    Swedish University Agriculture Science.
    Destouni, Georgia
    Swedish University Agriculture Science.
    Abrahamsson, Katarina
    Gothenburg University.
    Andersson, Lotta
    Linköping University, Department of Thematic Studies, Centre for Climate Science and Policy Research. Linköping University, Department of Thematic Studies, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Johnson, Richard K
    Swedish University Agriculture Science.
    Rodhe, Johan
    Gothenburg University.
    Hjerdt, Niclas
    Swedish Meteorological & Hydrological Institute.
    Nature as the "Natural" Goal for Water Management: A Conversation2009In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, no 4, p. 209-214Article in journal (Other academic)
    Abstract [en]

    The goals for water-quality and ecosystem integrity are often defined relative to "natural" reference conditions in many water-management systems, including the European Union Water Framework Directive. This paper examines the difficulties created for water management by using "natural" as the goal. These difficulties are articulated from different perspectives in an informal (fictional) conversation that takes place after a workshop on reference conditions in water-resources management. The difficulties include defining the natural state and modeling how a system might be progressed toward the natural, as well as the feasibility and desirability of restoring a natural state. The paper also considers the appropriateness for developing countries to adopt the use of natural as the goal for water management. We conclude that failure to critically examine the complexities of having "natural" as the goal will compromise the ability to manage the issues that arise in real basins by not making the ambiguities associated with this "natural" goal explicit. This is unfortunate both for the western world that has embraced this model of "natural as the goal" and for the developing world in so far as they are encouraged to adopt this model.

  • 387. Bishop, Kevin
    et al.
    Beven, Keith
    Destouni, Georgia
    Abrahamsson, Katarina
    Andersson, Lotta
    SMHI, Core Services.
    Johnson, Richard K.
    Rodhe, Johan
    Hjerdt, Niclas
    SMHI, Core Services.
    Nature as the "Natural" Goal for Water Management: A Conversation2009In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, no 4, p. 209-214Article in journal (Other academic)
    Abstract [en]

    The goals for water-quality and ecosystem integrity are often defined relative to "natural" reference conditions in many water-management systems, including the European Union Water Framework Directive. This paper examines the difficulties created for water management by using "natural" as the goal. These difficulties are articulated from different perspectives in an informal (fictional) conversation that takes place after a workshop on reference conditions in water-resources management. The difficulties include defining the natural state and modeling how a system might be progressed toward the natural, as well as the feasibility and desirability of restoring a natural state. The paper also considers the appropriateness for developing countries to adopt the use of natural as the goal for water management. We conclude that failure to critically examine the complexities of having "natural" as the goal will compromise the ability to manage the issues that arise in real basins by not making the ambiguities associated with this "natural" goal explicit. This is unfortunate both for the western world that has embraced this model of "natural as the goal" and for the developing world in so far as they are encouraged to adopt this model.

  • 388.
    Bishop, Kevin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Gebrehiwot, Solomon
    SLU Aquatic Sciences and Assessment.
    Taye, Ayale
    Awassa University, Ethiopia.
    Forest Cover and Stream Flow in a Headwater of the Blue Nile: Complementing Observational Data Analysis with Community Perception2010In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 39, no 4, p. 284-294Article in journal (Refereed)
    Abstract [en]

    This study analyses the relation of forest cover and stream flow on the 266 km2 Koga watershed in the headwaters of Blue Nile Basin using both observed hydrological data and community perception. The watershed went from 16% forest cover in 1957 to 1% by 1986. The hydrological record did not reveal changes in the flow regime between 1960 and 2002 despite the reduction in forest area. This agrees with the perception of the downstream community living near the gauging station. The upstream community, however, reported both decreases in low flows and increases in high flows shortly after the forest cover was reduced. The upstream deforestation effect appeared to have been buffered by a wetland lower in the watershed. This study concludes that community perception can be a complement to observational data for better understanding how forest cover influences the flow regime.

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  • 389.
    Bishop, Kevin
    et al.
    SLU-Ultuna.
    Lyon, Steve
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Dahlke, Helen
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    The relationship between land use and water2012In: EOS: Transactions, ISSN 0096-3941, E-ISSN 2324-9250, Vol. 93, no 28, p. 259-Article in journal (Refereed)
    Abstract [en]

    Water As the Mirror of Landscapes: How Useful a Hypothesis for Resource Management?; Uppsala, Sweden, 28–29 March 2012 The question posed in the title of this workshop formed its focus as an international group of more than 50 researchers and managers gathered to discuss our current level of understanding of land-water interactions and the potential impacts this has for resource management. Special emphasis was placed on the Ethiopian highlands, which deliver more than 85% of the flow in the Nile in Egypt. The 2-day workshop, held at the Swedish University of Agricultural Sciences in Uppsala, was cosponsored by the Swedish Ministry for Foreign Affairs as part of its special allocation for global food security and by the International Union of Forest Research Organizations' Unit 3.05, Forest Operations Ecology.

  • 390.
    Bishop, Kevin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala.
    Seibert, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    A primer for hydrology: the beguiling simplicity of Water's journey from rain to stream at 30 Preface2015In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 29, no 16, p. 3443-3446Article in journal (Other academic)
    Abstract [en]

    Water's journey from rain to stream by Harald Grip and Allan Rodhe (1985, in Swedish: Vattnets vag fran regn till back) was one of the first textbooks to present groundwater contributions as a major feature of runoff generation, with implications for water quality and management. Three decades later, we have the privilege of presenting a special issue of Hydrological Processes, Runoff Generation in a Nordic Light: 30Years with Water's Journey from Rain to Stream' that seeks to introduce the book to a larger audience and continue the journey of ideas that the authors set in motion with their book.

  • 391.
    Bishop, Kevin
    et al.
    Uppsala University.
    Seibert, Jan
    Uppsala University, Switzerland.
    Nyberg, Lars
    Karlstad University, Faculty of Social and Life Sciences, Centre for Climate and Safety.
    Rodhe, Allan
    Uppsala University.
    Water storage in a till catchment: II: Implications of transmissivity feedback for flow paths and turnover times2011In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 25, no 25, p. 3950-3959Article in journal (Refereed)
    Abstract [en]

    This paper explores the flow paths and turnover times within a catchment characterized by the transmissivity feedback mechanism where there is a strong increase in the saturated hydraulic conductivity towards the soil surface and precipitation inputs saturate progressively more superficial layers of the soil profile. The analysis is facilitated by the correlation between catchment water storage and groundwater levels, which made it possible to model the daily spatial distribution of water storage, both vertically in different soil horizons and horizontally across a 6300-m2 till catchment. Soil properties and episodic precipitation input dynamics, combined with the influence of topographic features, concentrate flow in the horizontal, vertical, and temporal dimensions. Within the soil profile, there was a vertical concentration of lateral flow to superficial soil horizons (upper 30 cm of the soil), where much of the annual flow occurred during runoff episodes. Overland flow from a limited portion of the catchment can contribute to peak flows but is not a necessary condition for runoff episodes. The spatial concentration of flow, and the episodic nature of runoff events, resulted in a strong and spatially structured differentiation of local flow velocities within the catchment. There were large differences in the time spent by the laterally flowing water at different depths, with turnover times of lateral flow across a 1-m-wide soil pedon ranging from under 1 h at 10- to 20-cm depth to a month at 70- to 80-cm depth. In many regards, the hydrology of this catchment appears typical of the hydrology in till soils, which are widespread in Fenno-Scandia.

  • 392.
    Bizet, Alicia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Risker och åtgärder för saltvatteninträngning i dricksvattenbrunnar i ett nutids- och framtidsperspektiv2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Just over one million inhabitants in Sweden are dependent on individual drinking water supply from groundwater. When the groundwater levels are too low in a groundwater reservoir, it can lead to saltwater intrusion in drinking water wells. The purpose of this study was to establish whether topography, distance to sea, well depth, soil depth and type of soil correlated with chloride in drinking water, to investigate whether there is a risk for saltwater intrusion in a future changed climate, due to climate change, and to investigate if there are any measures to minimize saltwater intrusion. 

    Kendall’s tau was used to investigate if there were any significant correlations between chloride and topography, distance to sea, well depth and soil depth. Wilcoxon rank sum test was used to investigate if there was a significant difference between the soil types. In this study the results only showed a significant correlation between chloride and distance to sea (p=0,000341) and between chloride and topography (p=0,0124). There was no significant correlation between chloride and the rest of the parameters. However, earlier research has shown that there is a correlation between chloride and all previous mentioned parameters. There was a significant correlation between topography and well depth, which can imply that the wells are drilled shallower in lowland areas. Regarding the soil depth connected to chloride, it is assumed that the soil depth is too thin (about one meter) to see any clear results, since a shallow soil depth won’t affect the groundwater recharge enough. This could also contribute to no significant difference between chloride and soil types. 

    For the second part of the study a model was built in Matlab, to investigate if and how climate change will affect changes in groundwater levels and therefore if it will influence saltwater intrusion. The reference period was 2004-2020 and the future scenarios were RCP4.5 and RCP8.5, which were divided into two periods: 2021-2060 and 2061-2099. The model showed lower groundwater levels in the future, which can imply there is a greater risk of saltwater intrusion. Although there are multiple limitations and the model could be made more nuanced. 

    For the third part of this study, a literature study was made, where seven different measures where investigated: to control groundwater abstraction, to install waterefficient techniques in households, to drill shallower wells in risk areas, reversed osmosis, ADR (abstraction, desalination, recharge) and SWT (subsurface water technologies). These were compared to each other, where advantages and disadvantages were balanced against each other. Overall, preventative measures are preferable, although SWT and ADR are better than reversed osmosis for already contaminated water. 

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  • 393. Bjork, Goran
    et al.
    Nordberg, Kjell
    Arneborg, Lars
    SMHI, Research Department, Oceanography.
    Bornmalm, Lennart
    Harland, Rex
    Robijn, Ardo
    Odalen, Malin
    Seasonal oxygen depletion in a shallow sill fjord on the Swedish west coast2017In: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 175, p. 1-14Article in journal (Refereed)
  • 394. Bjork, Goran
    et al.
    Stranne, Christian
    Borenäs, Karin
    SMHI, Core Services.
    The Sensitivity of the Arctic Ocean Sea Ice Thickness and Its Dependence on the Surface Albedo Parameterization2013In: Journal of Climate, ISSN 0894-8755, E-ISSN 1520-0442, Vol. 26, no 4, p. 1355-1370Article in journal (Refereed)
    Abstract [en]

    In this study, the response of sea ice thickness to changes in the external forcing is investigated and particularly how this response depends on the surface albedo formulation by means of a one-dimensional coupled ocean-ice-atmosphere model. The main focus is on the thickness response to the atmospheric heat advection F-wall, solar radiation F-SW, and amount of snow precipitation S-prec. Different albedo parameterization schemes [ECHAM5, CSIRO, and Community Climate System Model, version 3 (CCSM3)] representing albedos commonly used in global climate models are compared together with more simplified schemes. Using different albedo schemes with the same external forcing produces large differences in ice thickness. The ice thickness response is similar for all realistic albedo schemes with a nearly linear decrease with increasing F-wall in the perennial ice regime and with a steplike transition into seasonal ice when F-wall exceeds a certain threshold. This transition occurs at an annual-mean ice thickness of 1.7-2.0 m. Latitudinal differences in solar insolation generally leads to increasing ice thickness toward the North Pole. The snow response varies significantly depending on which albedo scheme is used. The ECHAM5 scheme yields thinner ice with S-prec, the CSIRO scheme gives ice thickness nearly independent of S-prec, and with the CCSM3 scheme the ice thickness decreases with S-prec. A general result is that the modeled ice cover is rather sensitive to positive perturbations of the external heat supply when it is close to the transition such that just a small increase of, for example, F-wall can force the ice cover into the seasonal regime.

  • 395. Björk, G
    et al.
    Nohr, C
    Gustafsson, BG
    Lindberg, Amund E. B.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Ice dynamics in the Bothnian Bay inferred from ADCP measurements2008In: Tellus. Series A, Dynamic meteorology and oceanography, ISSN 0280-6495, E-ISSN 1600-0870, Vol. 60, no 1, p. 178-188Article in journal (Refereed)
    Abstract [en]

    A bottom mounted ADCP has monitored the ice motion and thickness in Bothnian Bay, Baltic Sea during the entire winter season 2004. The ADCP was deployed at 20 m depth at Falkensgrund well outside the land fast ice zone. The data shows that the ice motion is primarily driven by the wind but with a clear influence of internal ice stresses. The ice stresses become more dominant as the ice grow thicker with increasing number of observations with nearly stationary ice for relatively high wind speeds. A clear dependence of the ice/wind speed ratio to wind shifts is detected with higher ratio in the new wind direction. The effect of strain hardening is also seen in several events as decreasing ice speed, sometimes to zero, in spite of constant wind speed and wind direction. A rough force balance computation gives a compressive ice strength of about  9 × 104 N m−2 , which is much larger than normally used in numerical ice models. The ice thickness data show numerous ice ridges with ice draft well above 1 m passing the instrument. The ridges make up a large portion, 30–50%, of the total ice volume showing that dynamical processes are important for the total ice production in the Bothnian Bay.

  • 396.
    Björk, Mats
    et al.
    Stockholm Univ, Dept Ecol Environm & Plant Sci, S-10691 Stockholm, Sweden..
    Rosenqvist, Gunilla
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Gröndahl, Fredrik
    KTH, Royale Inst Technol, KTH Teknikringen 10B, Stockholm, Sweden.;Dept Sustainable Dev Environm Sci & Engn, S-10044 Stockholm, Sweden..
    Bonaglia, Stefano
    Univ Gothenburg, Dept Marine Sci, Box 461, S-40530 Gothenburg, Sweden..
    Methane emissions from macrophyte beach wrack on Baltic seashores2023In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 52, p. 171-181Article in journal (Refereed)
    Abstract [en]

    Beach wrack of marine macrophytes is a natural component of many beaches. To test if such wrack emits the potent greenhouse gas methane, field measurements were made at different seasons on beach wrack depositions of different ages, exposure, and distance from the water. Methane emissions varied greatly, from 0 to 176 mg CH4-C m(-2) day(-1), with a clear positive correlation between emission and temperature. Dry wrack had lower emissions than wet. Using temperature data from 2016 to 2020, seasonal changes in fluxes were calculated for a natural wrack accumulation area. Such calculated average emissions were close to zero during winter, but peaked in summer, with very high emissions when daily temperatures exceeded 20 degrees C. We conclude that waterlogged beach wrack significantly contributes to greenhouse gas emissions and that emissions might drastically increase with increasing global temperatures. When beach wrack is collected into heaps away from the water, the emissions are however close to zero.

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  • 397.
    Blackburn, Nicholas
    et al.
    MicroWISE, Ebeltoft, Denmark.
    Haecky, Pia
    MicroWISE, Ebeltoft, Denmark.
    Jurgensone, Iveta
    Latvian Institute of Aquatic Ecology, Riga, Latvia.
    Griniene, Evelina
    Marine Research Institute, Klaipėda University, Klaipėda, Lithuania.
    Brugel, Sonia
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Umeå University, Faculty of Science and Technology, Umeå Marine Sciences Centre (UMF).
    Andersson, Agneta
    Umeå University, Faculty of Science and Technology, Umeå Marine Sciences Centre (UMF). Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Carstensen, Jacob
    Department of Ecoscience, Aarhus University, Roskilde, Denmark.
    The use of an automated organism tracking microscope in mesocosm experiments2022In: Limnology and Oceanography: Methods, E-ISSN 1541-5856, Vol. 20, no 12, p. 768-780Article in journal (Refereed)
    Abstract [en]

    A method for automatically counting and measuring sizes and motility behavior of zooplankton and phytoplankton in water samples is presented. Two video cameras are focused on separate optical chambers of different sizes. The chambers are filled and emptied repeatedly by synchronized pumps. Real-time motion analysis is performed by computer on the respective video feeds. Fluorescence from chlorophyll a (Chl a) is imaged at single pixel resolution. Measured parameters for individual organisms include size, swimming velocity, motility patterns, and chlorophyll fluorescence density. The system was tested during a mesocosm experiment where it was mounted on one of several mesocosm columns. The results were validated against Chl a measurements and microscopy counts. A sampling interval of 1 per day revealed detailed dynamics of chlorophyll activity as well as shifts in both the phytoplankton and zooplankton community structure over the course of a month. A helix coefficient, a metric related to organism motility behavior, showed substantial variation over time, consistent with changing plankton communities. Sampling rates as frequent as 1 per hour enables detailed analysis of diurnal vertical migration and similar phenomena at fixed sampling points.

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  • 398.
    Blasiak, Robert
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Jouffray, Jean-Baptiste
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Norström, Albert V.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Queiroz, Cibele
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Wabnitz, Colette C. C.
    Österblom, Henrik
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    The Ocean Decade as an instrument of peace2023In: Current Opinion in Environmental Sustainability, ISSN 1877-3435, E-ISSN 1877-3443, Vol. 64, article id 101319Article in journal (Refereed)
    Abstract [en]

    The United Nations Decade of Ocean Science for Sustainable Development 2021-2030 (the 'Ocean Decade') is poised to stimulate new cooperation for ocean science, but makes no mention of conflict or peace. We contend that this is a missed opportunity, and use an environmental peacebuilding typology to review how ocean science has historically contributed to peace. Such considerations are timely in the context of an increasingly complex and multidimensional ocean risk landscape, due among other things to unprecedented growth in the extent and intensity of ocean uses, and increasing conflict potential as the ocean becomes a more crowded and coveted place. We conclude by proposing the Ocean Decade Implementation Plan be appended to include an eighth intended outcome: 'A Peaceful Ocean'.

  • 399.
    Blauhut, Veit
    et al.
    Univ Freiburg, Environm Hydrol Syst, Fac Environm & Nat Resources, Freiburg, Germany..
    Stoelzle, Michael
    Univ Freiburg, Environm Hydrol Syst, Fac Environm & Nat Resources, Freiburg, Germany..
    Ahopelto, Lauri
    Aalto Univ, Water & Dev Res Grp, Sch Engn, Aalto, Finland.;Finnish Environm Inst, Freshwater Ctr, Helsinki, Finland..
    Brunner, Manuela, I
    Univ Freiburg, Environm Hydrol Syst, Fac Environm & Nat Resources, Freiburg, Germany..
    Teutschbein, Claudia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Wendt, Doris E.
    Univ Birmingham, Sch Geog Earth & Environm Sci, Birmingham, W Midlands, England.;Univ Bristol, Dept Civil Engn, Bristol, Avon, England..
    Akstinas, Vytautas
    Lithuanian Energy Inst, Lab Hydrol, Kaunas, Lithuania..
    Bakke, Sigrid J.
    Univ Oslo, Dept Geosci, Oslo, Norway..
    Barker, Lucy J.
    UK Ctr Ecol & Hydrol, Wallingford, Oxon, England..
    Bartosova, Lenka
    Global Change Res Inst CAS, Brno, Czech Republic..
    Briede, Agrita
    Univ Latvia, Fac Geog & Earth Sci, Riga, Latvia..
    Cammalleri, Carmelo
    European Commiss, Joint Res Ctr, Ispra, Italy..
    Kalin, Ksenija Cindric
    Croatian Meteorol & Hydrol Serv, Div Dev Climate Prod & Applicat, Zagreb, Croatia..
    De Stefano, Lucia
    Univ Complutense Madrid, Fac Ciencias Geol, Madrid, Spain..
    Fendekova, Miriam
    Comenius Univ, Dept Hydrogeol, Fac Nat Sci, Ilkovicova 6, Bratislava 84215, Slovakia..
    Finger, David C.
    Reykjavik Univ, Sch Engn, Reykjavik, Iceland.;Johannes Kepler Univ Linz, Energieinst, Linz, Austria..
    Huysmans, Marijke
    Vrije Univ Brussel, Dept Hydrol & Hydraul Engn, Brussels, Belgium..
    Ivanov, Mirjana
    Inst Hydrometeorol & Seismol, Podgorica, Montenegro..
    Jaagus, Jaak
    Univ Tartu, Dept Geog, Inst Ecol & Earth Sci, Tartu, Estonia..
    Jakubinsky, Jiri
    Global Change Res Inst CAS, Brno, Czech Republic..
    Krakovska, Svitlana
    Ukrainian Hydrometeorol Inst, Lab Appl Climatol, Kiev, Ukraine..
    Laaha, Gregor
    Univ Nat Resources & Life Sci, Inst Stat, Vienna, Austria..
    Lakatos, Monika
    Hungarian Meteorol Serv, Budapest, Hungary..
    Manevski, Kiril
    Aarhus Univ, Dept Agroecol, Tjele, Denmark..
    Andersen, Mathias Neumann
    Aarhus Univ, Dept Agroecol, Tjele, Denmark..
    Nikolova, Nina
    Sofia Univ St Kliment Ohridski, Dept Climatol Hydrol & Geomorphol, Fac Geol & Geog, Sofia, Bulgaria..
    Osuch, Marzena
    Polish Acad Sci, Inst Geophys, Warsaw, Poland..
    van Oel, Pieter
    Wageningen Univ, Water Resources Management Grp, Wageningen, Netherlands..
    Radeva, Kalina
    Sofia Univ St Kliment Ohridski, Dept Climatol Hydrol & Geomorphol, Fac Geol & Geog, Sofia, Bulgaria..
    Romanowicz, Renata J.
    Polish Acad Sci, Inst Geophys, Warsaw, Poland..
    Toth, Elena
    Univ Bologna, Dept Civil Chem Environm & Mat Engn, Bologna, Italy..
    Trnka, Mirek
    Global Change Res Inst CAS, Brno, Czech Republic..
    Urosev, Marko
    Serbian Acad Arts & Sci, Geog Inst Jovan Cvijic, Belgrade, Serbia..
    Reguera, Julia Urquijo
    Univ Politecn Madrid, Dept Agroforestry Engn, Escuela Tecn Super Ingn Agron & Biosistemas, Madrid, Spain..
    Sauquet, Eric
    INRAE, RiverLy, Villeurbanne, France..
    Stevkov, Aleksandra
    Natl Hydrometeorol Serv, Dept Meteorol, Skopje, North Macedonia..
    Tallaksen, Lena M.
    Univ Oslo, Dept Geosci, Oslo, Norway..
    Trofimova, Iryna
    Ukrainian Hydrometeorol Inst, Lab Appl Climatol, Kiev, Ukraine..
    Van Loon, Anne F.
    Vrije Univ Amsterdam, Inst Environm Studies, Amsterdam, Netherlands..
    van Vliet, Michelle T. H.
    Univ Utrecht, Dept Phys Geog, Utrecht, Netherlands..
    Vidal, Jean-Philippe
    INRAE, RiverLy, Villeurbanne, France..
    Wanders, Niko
    Univ Utrecht, Dept Phys Geog, Utrecht, Netherlands..
    Werner, Micha
    IHE Delft Inst Water Educ, Water Resources & Ecosyst Dept, Delft, Netherlands..
    Willems, Patrick
    Katholieke Univ Leuven, Hydraul & Geotech Sect, Dept Civil Engn, Leuven, Belgium..
    Zivkovic, Nenad
    Univ Belgrade, Fac Geog, Belgrade, Serbia..
    Lessons from the 2018-2019 European droughts: a collective need for unifying drought risk management2022In: Natural hazards and earth system sciences, ISSN 1561-8633, E-ISSN 1684-9981, Vol. 22, no 6, p. 2201-2217Article in journal (Refereed)
    Abstract [en]

    Drought events and their impacts vary spatially and temporally due to diverse pedo-climatic and hydrologic conditions, as well as variations in exposure and vulnerability, such as demographics and response actions. While hazard severity and frequency of past drought events have been studied in detail, little is known about the effect of drought management strategies on the actual impacts and how the hazard is perceived by relevant stakeholders. In a continental study, we characterised and assessed the impacts and the perceptions of two recent drought events (2018 and 2019) in Europe and examined the relationship between management strategies and drought perception, hazard, and impact. The study was based on a pan-European survey involving national representatives from 28 countries and relevant stakeholders responding to a standard questionnaire. The survey focused on collecting information on stakeholders' perceptions of drought, impacts on water resources and beyond, water availability, and current drought management strategies on national and regional scales. The survey results were compared with the actual drought hazard information registered by the European Drought Observatory (EDO) for 2018 and 2019. The results highlighted high diversity in drought perception across different countries and in values of the implemented drought management strategies to alleviate impacts by increasing national and sub-national awareness and resilience. The study identifies an urgent need to further reduce drought impacts by constructing and implementing a European macro-level drought governance approach, such as a directive, which would strengthen national drought management and mitigate damage to human and natural assets.

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  • 400. Blauhut, Veit
    et al.
    Stoelzle, Michael
    Ahopelto, Lauri
    Brunner, Manuela I.
    Teutschbein, Claudia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Wendt, Doris E.
    Akstinas, Vytautas
    Bakke, Sigrid J.
    Barker, Lucy J.
    Bartošová, Lenka
    Briede, Agrita
    Cammalleri, Carmelo
    De Stefano, Lucia
    Fendeková, Miriam
    Finger, David C.
    Huysmans, Marijke
    Ivanov, Mirjana
    Jaagus, Jaak
    Jakubínský, Jiří
    Kalin, Ksenija Cindrić
    Krakovska, Svitlana
    Laaha, Gregor
    Lakatos, Monika
    Manevski, Kiril
    Neumann Andersen, Mathias
    Nikolova, Nina
    Osuch, Marzena
    van Oel, Pieter
    Radeva, Kalina
    Romanowicz, Renata J.
    Toth, Elena
    Trnka, Mirek
    Urošev, Marko
    Urquijo Reguera, Julia
    Sauquet, Eric
    Stevkova, Silvana
    Tallaksen, Lena M.
    Trofimova, Iryna
    van Vliet, Michelle T. H.
    Vidal, Jean-Philippe
    Wanders, Niko
    Werner, Micha
    Willems, Patrick
    Živković, Nenad
    Lessons from the 2018–2019 European droughts: A collective need for unifying drought risk management2021In: Natural hazards and earth system sciences, ISSN 1561-8633, E-ISSN 1684-9981Article in journal (Other academic)
    Abstract [en]

    Drought events and their impacts vary spatially and temporally due to diverse pedo-climatic and hydrologic conditions, as well as variations in exposure and vulnerability, such as demographics and response actions. While hazardous severity and frequency of past drought events have been studied in detail, little is known about the effect of drought management strategies on the actual impacts, and how the hazard is perceived by relevant stakeholders for inducing action. In a continental study, we characterised and assessed the impacts and the perceptions of two recent drought events (2018 and 2019) in Europe and examined the relationship between management strategies and drought perception, hazard and impacts. The study was based on a pan-European survey involving national representatives from 28 countries and relevant stakeholders responding to a standard questionnaire. The survey focused on collecting information on stakeholders’ perceptions of drought, impacts on water resources and beyond, water availability and current drought management strategies at national and regional scales. The survey results were compared with the actual drought hazard information registered by the European Drought Observatory (EDO) for 2018 and 2019. The results highlighted high diversity in drought perceptions across different countries and in values of implemented drought management strategies to alleviate impacts by increasing national and sub-national awareness and resilience. The study concludes with an urgent need to further reduce drought impacts by constructing and implementing a European macro-level drought governance approach, such as a directive, which would strengthen national drought management and lessen harm to human and natural potentials.

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