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  • 1.
    Abdel-Fattah, Dina
    et al.
    UiT – The Arctic University of Norway, Norway; University of Alaska Fairbanks, USA.
    Danielson, Mats
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. International Institute for Applied Systems Analysis, Austria.
    Ekenberg, Love
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. International Institute for Applied Systems Analysis, Austria.
    Hock, Regine
    University of Alaska Fairbanks, USA; University of Oslo, Norway.
    Trainor, Sarah
    University of Alaska Fairbanks, USA.
    Application of a structured decision-making process in cryospheric hazard planning: Case study of Bering Glacier surges on local state planning in Alaska2024In: Journal of Multi-Criteria Decision Analysis, ISSN 1057-9214, E-ISSN 1099-1360, Vol. 31, no 1-2, article id e1825Article in journal (Refereed)
    Abstract [en]

    Surging glaciers are glaciers that experience rapidly accelerated glacier flow over a comparatively short period of time. Though relatively rare worldwide, Alaska is home to the largest number of surge-type glaciers globally. However, their impact on the broader socioecological system in the state is both poorly understood and under-researched, which poses a challenge in developing appropriate sustainability decisions in Alaska. We investigated how the surge patterns of the Bering Glacier in Alaska have potentially devastating effects on the local ecological biodiversity of its watershed via a structured decision-making analysis of the different possible consequences. Specifically, this analysis was conducted to explore the various outcomes of a Bering Glacier surge particularly if humans have an increased presence near the glacier due to the area potentially becoming a state park. This work explored the benefits of applying a risk and decision analytical framework in a cryosphere context, to better understand the socioeconomic impact of glacier surges. This is a novel approach in which a decision analysis tool was used to better understand an environmental sustainability challenge, offering an innovative method to support the achievement of the United Nations Sustainability Development Goals in Alaska. We therefore emphasise the need for integrated biophysical and socioeconomic analyses when it comes to understanding glacier hazards. Our research highlights the importance of understanding and researching biophysical changes as well as using a structured decision-making process for complicated hazard planning scenarios, exemplified via glaciated regions in Alaska, in order to create adaptation strategies that are sustainable and encompass the range of possible outcomes.

  • 2. Abdennadher, Jihene
    et al.
    Boukthir, Moncef
    Döös, Kristofer
    Stockholm University, Faculty of Science, Department of Meteorology .
    Water Mass Transformation in a Secluded Bay of the Mediterranean Sea2023In: Tellus. Series A, Dynamic meteorology and oceanography, ISSN 0280-6495, E-ISSN 1600-0870, Vol. 75, no 1, p. 375-391Article in journal (Refereed)
    Abstract [en]

    This case study demonstrates how water transformation in a secluded bay can be investigated using a range of Lagrangian analysis methods that can be calculated with a mass-conserving Lagrangian trajectory model. The study focuses on analysing the water mass transformation and overturning circulation in the Gulf of Gabès. The gradual transformation of water masses flowing through the Gulf was analysed using model-simulated Lagrangian trajectories. It was found that the overturning circulation in the Gulf gradually deepens, although it is falsely exaggerated by up to 50 metres when computed as a simple longitude-depth Lagrangian stream function.

    The Lagrangian method enabled the determination of the spatial dependence of transit time. The analysis revealed that most of the water in the Gulf has a transit time short enough to adjust to seasonal variability. However, in the innermost part of the Gulf, there exists an anticyclonic vortex that tends to trap water on longer timescales, preventing it from adjusting to seasonal variability. The trajectories were computed using velocity and mass transport fields from a high-resolution (1/96°) hydrodynamic ROMS model, which includes the relatively strong tides in this region of the Mediterranean.

  • 3.
    Abdoush, Diala
    et al.
    SMHI, Samhällsplanering.
    Björkert, Daniel
    SMHI, Samhällsplanering.
    Danielsson, Kristina
    SMHI, Samhällsplanering.
    Engblom, Anna
    SMHI, Samhällsplanering.
    Johnsen, Åsa
    SMHI, Samhällsplanering.
    Pettersson, Ola
    SMHI, Samhällsplanering.
    SVAR 20222024Report (Other academic)
    Abstract [en]

     

    SVAR 2022 brings significant changes compared to previous versions of SVAR, the Swedish Water Archive. The shift towards utilizing current and detailed data, coupled with automated workflows, has led to more consistent products created uniformly across the entire country. Automation has also resulted in a more consistent quality across the dataset, distinguishing it from previous manual methods.

    The primary focus of SVAR 2022 has been to meet the needs of water authorities for water bodies and to provide support for SMHI's S-HYPE model and Coastal Zone model. Some products have been discontinued while others have been introduced. Many have also undergone changes, both in terms of geometry and attributes, with the goal of refining and cleaning to produce clearer and more accurate products. For example, drainage basins are now only delimited by watershed boundaries, unlike previous versions where coastlines were also considered. Additionally, main drainage basins now contain only primary drainage areas, while small coastal areas between outlets are now found in the new BARO product.

    The coverage of SVAR 2022 primarily extends within Sweden's territories, meaning products are developed solely within Sweden's territorial borders. Drainage basins have therefore not been generated outside Sweden's borders; instead, foreign drainage basins have been downloaded and adapted to the Swedish ones along the border. Unlike previous SVAR versions, marine areas now only extend to the territorial sea boundary in the ocean.

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    SVAR 2022
  • 4.
    Abdulhameed, Isam Mohammed
    et al.
    University of Anbar, College of Engineering, Upper Euphrates Basin Developing Centre, Ramadi, Iraq.
    Sulaiman, Sadeq Oleiwi
    University of Anbar, College of Engineering, Dams and Water Resources Department, Ramadi, Iraq.
    Ahmed Najm, Abu Baker
    University of Anbar, College of Engineering, Dams and Water Resources Department, Ramadi, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Optimising water resources management by Using Water Evaluation and Planning (WEAP) in the West of Iraq2022In: Journal of Water and Land Development, ISSN 1429-7426, no 53, p. 176-186Article in journal (Refereed)
    Abstract [en]

    Iraq has been suffering from decreasing Euphrates discharge due to the construction of dams within upstream countries and the use of surface irrigation systems. The country is facing a problem with meeting the increasing demand for water as a result of population growth and development in the industrial and agricultural sectors. Therefore, a simulation modelling was applied for western Iraq (Ramadi city as a case study) using the Water Evaluation and Planning System (WEAP) for the period 2018–2035. This research follows a four-step approach that involves: (i) evaluating the available water of the Euphrates River under declined water imports caused by the construction of dams in Turkey and Syria, (ii) assessing present and future water demands of the domestic, industrial, and agricultural sectors, (iii) improving water productivity (WP) by means of saving more water, (iv) estimating the economic returns under improved water use. The results showed that Iraq would face a serious problem in the coming years, represented by the limited storage of Haditha Dam, which is considered the strategic water storage site for the central and southern regions of Iraq. The study indicated the necessity of finding alternative sources of water supply by adopting new water management strategies to reduce the water deficit. 

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  • 5.
    Abhishek, Sarabjot
    et al.
    Dr BR Ambedkar Natl Inst Technol, Dept Phys, GT Rd Bye Pass, Jalandhar 144027, Punjab, India..
    Kaur, Sarabjot
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Mehra, Rohit
    Dr BR Ambedkar Natl Inst Technol, Dept Phys, GT Rd Bye Pass, Jalandhar 144027, Punjab, India..
    Estimation of Uranium and Related Health Risks Due to Consumption of Groundwater in Lower Himalayas2023In: Indian Journal of Pure & Applied Physics, ISSN 0019-5596, E-ISSN 0975-1041, Vol. 61, no 6, p. 478-483Article in journal (Refereed)
    Abstract [en]

    Exposure to uranium via ingestion of edible products may lead to serious health hazards when taken in quantities more than recommended limit. Hence, to assess the uranium content in groundwater and concerned health hazards 64 groundwater samples were collected from Hamirpur and Mandi districts of Himachal Pradesh. The samples were collected in pre monsoon season from the handpumps and bowries. The region lies in Lower Himalayan range which is storehouse of various granatic rocks. Presence of uranium deposits in Tileli (Mandi), Rajpura (Una), Lambehra (Hamirpur) makes the area more vulnerable for the study. The groundwater samples were analysed to measure concentration of uranium using LED Fluorimeter developed by Quantalase Private. Limited. The uranium concentration in groundwater samples varied from 0.25 to 17.29 & mu;g L-1, with an average value of 1.97. Uranium concentration in none of the samples surpassed the limit of 30 & mu;g L-1 recommended by WHO(2011), 60 & mu;g L-1 set by AERB(2004). Health risks were estimated in terms radiological and chemical toxicity for different isotopes of uranium. The calculated average mortality and morbidity risks were lower than the actual prescribed limit. The average Lifetime Average Daily Dose (LADD) was calculated as 0.04 and Hazard Quotient (HQ) below unity. Annual ingestion doses for different age groups were also measured which lies under safe limit. Thus, it is recommended that the groundwater is safe for consumption by public. Using Hair Compartment Model for uranium and mean daily uranium intake of 2.71 & mu;g for 60-year exposure period, organ specific doses due to uranium radioisotopes in prime organs/tissues and excretion rates via urine, faeces and hair pathway are estimated.

  • 6. Abiye, T. A.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Arsenic concentration in groundwater: Archetypal study from South Africa2019In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 9, article id 100246Article in journal (Refereed)
    Abstract [en]

    South Africa does not have significant surface water resources, which is often easily affected by unpredictable and rapidly changing climatic variables, due to its location in the arid and semi-arid climatic setting. In large part of the country, groundwater from weathered and fractured crystalline rocks plays pivotal role in sustaining the livelihood, often it contains toxic metals released from the host rocks. The host rocks that are responsible for arsenic release in groundwater are primarily enriched due to metamorphism and igneous processes that resulted in the enrichment of economic minerals. Preliminary assessment indicates that the main arsenic containing minerals are arsenopyrite (FeAsS), arsenical oxide, sulpharsenide, arsenopyritical reefs, leucopyrite, löllingite (FeAs2) and scorodite (FeAsO4·2H2O). Owing to the release of arsenic from highly mineralized rocks that constitute the aquifers, arsenic concentration in the groundwater reaches up to 253 μg/L (Namaqualand), 6150 μg/L (west of Johannesburg), about 500 μg/L in the Karoo aquifers, considerably higher than the WHO guideline value of 10 μg/L. Acid mine drainage from coal and gold mining is also found to be an important source of arsenic and other toxic metals in groundwater.

  • 7.
    Abong'o, Deborah
    et al.
    University of Nairobi, Kenya.
    Wandiga, Shem
    University of Nairobi. Kenya.
    Jumba, Isac
    University of Nairobi, Kenya.
    van den Brink, Paul
    Wageningen University, the Netherlands.
    Nazariwo, Betty
    Makerere University, Uganda.
    Madadi, Vincent
    University of Nairobi, Kenya.
    Wafula, Godfrey
    University of Nairobi, Kenya.
    Kylin, Henrik
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Nkedi-Kizza, Peter
    University of Florida, USA.
    Organochlorine pesticide residue levels in soil from the Nyando River catchment, Kenya2015In: Africa Journal of Physical Sciences, ISSN 2313-3317, Vol. 2, no 1, p. 18-32Article in journal (Refereed)
    Abstract [en]

    Soil samples were collected from six locations representative of the Nyando River catchment area of the Lake Victoria over a period of two years. Sampling was done four times in the year in February, May, September and December 2005 and 2006 in farms where maize, tea, sugar cane, coffee, rice and vegetables have been grown over the years. This coincided with the effects of different seasons and farming activities on residue levels of the pesticides in use. The objective was to investigate levels and distribution of organochlorine pesticides that have either been banned or are restricted for use in Kenya. Organochlorine pesticides investigated were DDT, lindane, aldrin, dieldrin, heptachlor, endrin, endosulfan (both α- and β- isomers and endosulfan sulphate), the sum is called “total” or Σendosulfan and methoxychlor. Prior to the ban or restriction in use, these pesticides had found wide applications in public health for control of disease vectors and in agriculture for control of crop pests. The analysis revealed presence of all the targeted pesticides with the highest mean concentrations for methoxychlor 140 ± 1.5 μg/kg, Σendosulfan (30 ± 2.1 μg/kg), aldrin (18 ± 0.28 μg/kg), respectively. The results show the presence of these pesticides in soils in the basin and this could be impacting negatively on the ecosystem health of the area.

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  • 8.
    Acosta Navarro, Juan Camilo
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Anthropogenic influence on climate through changes in aerosol emissions from air pollution and land use change2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Particulate matter suspended in air (i.e. aerosol particles) exerts a substantial influence on the climate of our planet and is responsible for causing severe public health problems in many regions across the globe. Human activities have altered the natural and anthropogenic emissions of aerosol particles through direct emissions or indirectly by modifying natural sources. The climate effects of the latter have been largely overlooked. Humans have dramatically altered the land surface of the planet causing changes in natural aerosol emissions from vegetated areas. Regulation on anthropogenic and natural aerosol emissions have the potential to affect the climate on regional to global scales. Furthermore, the regional climate effects of aerosol particles could potentially be very different than the ones caused by other climate forcers (e.g. well mixed greenhouse gases). The main objective of this work was to investigate the climatic effects of land use and air pollution via aerosol changes.

    Using numerical model simulations it was found that land use changes in the past millennium have likely caused a positive radiative forcing via aerosol climate interactions. The forcing is an order of magnitude smaller and has an opposite sign than the radiative forcing caused by direct aerosol emissions changes from other human activities. The results also indicate that future reductions of fossil fuel aerosols via air quality regulations may lead to an additional warming of the planet by mid-21st century and could also cause an important Arctic amplification of the warming. In addition, the mean position of the intertropical convergence zone and the Asian monsoon appear to be sensitive to aerosol emission reductions from air quality regulations. For these reasons, climate mitigation policies should take into consideration aerosol air pollution, which has not received sufficient attention in the past.

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    Anthropogenic influence on climate through changes in aerosol emissions from air pollution and land use change
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    Omslagsframsida
  • 9.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Schreyer, Lynn
    Washington State University, USA.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Lin, Hai
    University of Colorado Denver, USA.
    Pore-scale modeling of vapor transport in partially saturated capillary tube with variable area using chemical potential2016In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 52, no 9, p. 7023-7035Article in journal (Refereed)
    Abstract [en]

    Here we illustrate the usefulness of using the chemical potential as the primary unknown by modeling isothermal vapor transport through a partially saturated cylindrically symmetric capillary tube of variable cross-sectional area using a single equation. There are no fitting parameters and the numerical solutions to the equation are compared with experimental results with excellent agreement. We demonstrate that isothermal vapor transport can be accurately modeled without modeling the details of the contact angle, microscale temperature fluctuations, or pressure fluctuations using a modification of the Fick-Jacobs equation. We thus conclude that for a single, axisymmetric pore, the enhancement factor depends upon relative humidity boundary conditions at the liquid bridge interfaces, distance between liquid bridges, and bridge lengths.

  • 10. Addor, Nans
    et al.
    Rössler, Ole
    Köplin, Nina
    Huss, Matthias
    Weingartner, Rolf
    Seibert, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Robust changes and sources of uncertainty in the projected hydrological regimes of Swiss catchments2014In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 50, no 10, p. 7541-7562Article in journal (Refereed)
    Abstract [en]

    Projections of discharge are key for future water resources management. These projections are subject to uncertainties, which are difficult to handle in the decision process on adaptation strategies. Uncertainties arise from different sources such as the emission scenarios, the climate models and their postprocessing, the hydrological models, and the natural variability. Here we present a detailed and quantitative uncertainty assessment, based on recent climate scenarios for Switzerland (CH2011 data set) and covering catchments representative for midlatitude alpine areas. This study relies on a particularly wide range of discharge projections resulting from the factorial combination of 3 emission scenarios, 10–20 regional climate models, 2 postprocessing methods, and 3 hydrological models of different complexity. This enabled us to decompose the uncertainty in the ensemble of projections using analyses of variance (ANOVA). We applied the same modeling setup to six catchments to assess the influence of catchment characteristics on the projected streamflow, and focused on changes in the annual discharge cycle. The uncertainties captured by our setup originate mainly from the climate models and natural climate variability, but the choice of emission scenario plays a large role by the end of the 21st century. The contribution of the hydrological models to the projection uncertainty varied strongly with catchment elevation. The discharge changes were compared to the estimated natural decadal variability, which revealed that a climate change signal emerges even under the lowest emission scenario (RCP2.6) by the end of the century. Limiting emissions to RCP2.6 levels would nevertheless reduce the largest regime changes by the end of the century by approximately a factor of two, in comparison to impacts projected for the high emission scenario SRES A2. We finally show that robust regime changes emerge despite the projection uncertainty. These changes are significant and are consistent across a wide range of scenarios and catchments. We propose their identification as a way to aid decision making under uncertainty.

  • 11.
    Adem Esmail, Blal
    et al.
    Department of Civil, Environmental, and Mechanical Engineering, University of Trento, Via Mesiano 77, Trento, 38123, Italy.
    Geneletti, Davide
    Department of Civil, Environmental, and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy.
    Design and impact assessment of watershed investments: An approach based on ecosystem services and boundary work.2017In: Environmental impact assessment review, ISSN 0195-9255, E-ISSN 1873-6432, Vol. 62, p. 1-13Article in journal (Refereed)
    Abstract [en]

    Watershed investments, whose main aim is to secure water for cities, represent a promising opportunity for large-scale sustainability transitions in the near future. If properly designed, they promote activities in the watershed that enhance ecosystem services while protecting nature and biodiversity, as well as achieving other societal goals. In this paper, we build on the concepts of ecosystem services and boundary work, to develop and test an operative approach for designing and assessing the impact of watershed investments. The approach is structured to facilitate negotiations among stakeholders. Its strategic component includes setting the agenda; defining investment scenarios; and assessing the performance of watershed investments as well as planning for a follow-up. Its technical component concerns data processing; tailoring spatially explicit ecosystem service models; hence their application to design a set of “investment portfolios”, generate future land use scenarios, and model impacts on selected ecosystem services. A case study illustrates how the technical component can be developed in a data scarce context in sub-Saharan Africa in a way that is functional to support the steps of the strategic component. The case study addresses soil erosion and water scarcity-related challenges affecting Asmara, a medium-sized city in Eritrea, and considers urban water security and rural poverty alleviation as two illustrative objectives, within a ten-year planning horizon. The case study results consist in spatially explicit data (investment portfolio, land use scenario, impact on ecosystem services), which were aggregated to quantitatively assess the performance of different watershed investments scenarios, in terms of changes in soil erosion control. By addressing stakeholders' concerns of credibility, saliency, and legitimacy, the approach is expected to facilitate negotiation of objectives, definition of scenarios, and assessment of alternative watershed investments, ultimately, to contribute to implementing an adaptive watershed management.

  • 12.
    Adnan Abdu, Jihad
    et al.
    Halmstad University, School of Information Technology.
    Lundström, Philip
    Halmstad University, School of Information Technology.
    Water Quality Device: Testing Through Electronic Measurements2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Water is the source of all life, but unfortunately, the water quality is getting only worse due to many factors like overuse, contamination, indifference and even by nature itself. By identifying the problem, we are one step closer to solving the problem, and that is why an intelligent water quality device is required to examine water and detect impurities within it. In this project, we are developing a device that uses an entirely new method to measure water quality. Even though the theory behind the device is very advanced, the device is still primitive in its functions and needs development to increase the usefulness and accuracy of the measurements!

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  • 13.
    Adolfsson Lindahl, Frida
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Edholm, Sigrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Hagberg, Felicia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Holmgren, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Källbom, Jacob
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Magnusson, Astrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Våtmarkers potential att rena avloppsvatten från läkemedelsrester2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie genomfördes på uppdrag av det statliga forskningsinstitutet Formas. Syftet med rapporten var att undersöka hur effektiva våtmarker är som tilläggsrening av avloppsvatten, detta med avseende på reducering av läkemedel samt skadeeffekter på akvatiska organismer. Rapporten baserades på en tidigare studie utförd av Breitholtz et al. (2012) där mätningar av läkemedelshalter samt mortalitet och larvutveckling hos hoppkräftor, Nitocra spinipes, gjordes i fyra olika våtmarker.  De fyra våtmarkerna ligger i Eskilstuna, Oxelösund, Nynäshamn och Trosa. Deras mätningar undersökte mortalitet och larvutvecklingskvot för hoppkräftor i prover utspädda med bräckt vatten vid koncentration avloppsvatten på, 11,25 %; 22,5 %; 45% och 90 %. Proverna för läkemedelshalter späddes inte ut och enbart ett mätvärde per våtmark togs vid inflödet och utflödet.

    I denna rapport undersöktes dessa frågeställningar: (1) Är anlagda våtmarker som tilläggsrening en effektiv metod med avseende på skadeeffekter hos hoppkräftor, (2) till vilken grad reduceras halten läkemedel när våtmarker används som tilläggsrening samt (3) finns det ett samband mellan läkemedelsrester och hoppkräftornas överlevnad?

    För att besvara de tre frågeställningarna genomfördes en metaanalys av data från studien av Breitholtz et al. (2012). Hoppkräftors mortalitet, larvutvecklingskvot (LDR) och koncentration av läkemedel analyserades. Endast mortalitet och larvutvecklingskvot hade tillräckligt med data för utförande av en metaanalys. Läkemedelsanalysen kunde bara göras på en grundläggande nivå.

    Metaanalysen programmerades i MATLAB R2019b, där skillnaden i medelvärdet för mortalitet respektive larvutvecklingskvot beräknades mellan in- och utflöde för de fyra våtmarkerna. Skillnaderna för varje våtmark vägdes samman med invers-varians metoden för att få ett sammanvägt medelvärde. Analysen av läkemedel gjordes på nio läkemedel från Breitholtz et al. (2012). De nio valdes ut då de har pekats ut av Svenska Miljöinstitutet som intressanta ur ett avloppsreningsperspektiv. Excel användes för att göra enklare statistiska analyser mellan in- och utflöde i våtmarkerna. Slutligen gjordes en jämförelse mellan hoppkräftors skadeeffekter och läkemedelshalter genom att ta ut skillnaden i medelvärde mellan in- och utflöde.

    Resultatet från analyserna visade att när våtmarker användes som tilläggsrening minskade mortaliteten hos hoppkräftor för koncentrationerna 11,25 % och 90 % avloppsvatten. För koncentrationerna 22,5 % och 45 % fanns däremot ingen signifikant skillnad i mortalitet. Larvutvecklingskvoten minskade efter våtmarksbehandlingen för alla koncentrationer utom 90 %. Läkemedelshalten minskade i snitt med 30 % mellan inflöde och utflöde i våtmarkerna. För läkemedlen sulfametoxazol och oxazepam kunde dock en ökning ses efter behandling med våtmark. Ingen direkt trend kunde utläsas mellan läkemedelshalt och mortalitet hos hoppkräftor. Detta berodde troligtvis på att andra faktorer och föroreningar påverkade hoppkräftornas mortalitet och larvutvecklingskvot i högre grad än läkemedelshalterna.

    I studien kunde ingen slutsats dras om huruvida tilläggsvåtmarker är en effektiv reningsmetod med avseende på skadeeffekter hos hoppkräftor. Hoppkräftor är bra indikatorer på föroreningar i vattnet, dock är det svårt att bestämma vilka föroreningar som påverkar mest i detta fall. Detta medför att inga direkta samband mellan läkemedel och hoppkräftors mortalitet kunde påvisas i studien. De undersökta läkemedlen reducerades generellt. Eftersom mätningarna gjordes under vinterförhållanden då nedbrytningen i våtmarken är som minst effektiv bör resultatet ses som ett lägsta värde.

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  • 14. Aggarwal, Pradeep K.
    et al.
    Romatschke, Ulrike
    Araguas-Araguas, Luis
    Belachew, Dagnachew
    Longstaffe, Frederick J.
    Berg, Peter
    SMHI, Research Department, Hydrology.
    Schumacher, Courtney
    Funk, Aaron
    Proportions of convective and stratiform precipitation revealed in water isotope ratios2016In: Nature Geoscience, ISSN 1752-0894, E-ISSN 1752-0908, Vol. 9, no 8, p. 624-+Article in journal (Refereed)
  • 15.
    Agha Karimi, Armin
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Internal Variability Role on Estimating Sea Level Acceleration in Fremantle Tide Gauge Station2021In: Frontiers in Earth Science, E-ISSN 2296-6463, Vol. 9, article id 664947Article in journal (Refereed)
    Abstract [en]

    Low frequency internal signals bring challenges to signify the role of anthropogenic factors in sea level rise and to attain a certain accuracy in trend and acceleration estimations. Due to both spatially and temporally poor coverage of the relevant data sets, identification of internal variability patterns is not straightforward. In this study, the identification and the role of low frequency internal variability (decadal and multidecadal) in sea level change of Fremantle tide gauge station is analyzed using two climate indices, Pacific Decadal Oscillation (PDO) and Tripole Interdecadal Pacific Oscillation (TPI). It is shown that the multidecadal sea level variability is anticorrelated with corresponding components of climate indices in the Pacific Ocean, with correlation coefficients of -0.9 and -0.76 for TPI and PDO, respectively. The correlations are comparatively low on decadal time scale, -0.5 for both indices. This shows that internal variability on decadal and multidecadal scales affects the sea level variation in Fremantle unequally and thus, separate terms are required in trajectory models. To estimate trend and acceleration in Fremantle, three trajectory models are tested. The first model is a simple second-degree polynomial comprising trend and acceleration terms. Low passed PDO, representing decadal and interdecadal variabilities in Pacific Ocean, added to the first model to form the second model. For the third model, decomposed signals of decadal and multidecadal variability of TPI are added to the first model. In overall, TPI represents the low frequency internal variability slightly better than PDO for sea level variation in Fremantle. Although the estimated trends do not change significantly, the estimated accelerations varies for the three models. The accelerations estimated from the first and second models are statistically insignificant, 0.006 +/- 0.012 mm yr(-2) and 0.01 +/- 0.01 mm yr(-2), respectively, while this figure for the third model is 0.018 +/- 0.011 mm yr(-2). The outcome exemplifies the importance of modelling low frequency internal variability in acceleration estimations for sea level rise in regional scale.

  • 16.
    Agha Karimi, Armin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Bagherbandi, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. Univ Gävle, Fac Engn & Sustainable Dev, Gävle, Sweden..
    Horemuz, Milan
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Multidecadal Sea Level Variability in the Baltic Sea and Its Impact on Acceleration Estimations2021In: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 8Article in journal (Refereed)
    Abstract [en]

    Multidecadal sea level variation in the Baltic Sea is investigated from 1900 to 2020 deploying satellite and in situ datasets. As a part of this investigation, nearly 30 years of satellite altimetry data are used to compare with tide gauge data in terms of linear trend. This, in turn, leads to validation of the regional uplift model developed for the Fennoscandia. The role of North Atlantic Oscillation (NAO) in multidecadal variations of the Baltic Sea is also analyzed. Although NAO impacts the Baltic Sea level on seasonal to decadal time scales according to previous studies, it is not a pronounced factor in the multidecadal variations. The acceleration in the sea level rise of the basin is reported as statistically insignificant in recent studies or even decelerating in an investigation of the early 1990s. It is shown that the reason for these results relates to the global warming hiatus in the 1950s-1970s, which can be seen in all eight tide gauges used for this study. To account for the slowdown period, the acceleration in the basin is investigated by fitting linear trends to time spans of six to seven decades, which include the hiatus. These results imply that the sea level rise is accelerated in the Baltic Sea during the period 1900-2020.

  • 17.
    Agha Karimi, Armin
    et al.
    KTH.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. KTH.
    Huremuz, Milan
    KTH.
    Multidecadal sea level variability in the Baltic sea and its impact on acceleration estimations2021In: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 8, article id 702512Article in journal (Refereed)
    Abstract [en]

    Multidecadal sea level variation in the Baltic Sea is investigated from 1900 to 2020 deploying satellite and in situ datasets. As a part of this investigation, nearly 30 years of satellite altimetry data are used to compare with tide gauge data in terms of linear trend. This, in turn, leads to validation of the regional uplift model developed for the Fennoscandia. The role of North Atlantic Oscillation (NAO) in multidecadal variations of the Baltic Sea is also analyzed. Although NAO impacts the Baltic Sea level on seasonal to decadal time scales according to previous studies, it is not a pronounced factor in the multidecadal variations. The acceleration in the sea level rise of the basin is reported as statistically insignificant in recent studies or even decelerating in an investigation of the early 1990s. It is shown that the reason for these results relates to the global warming hiatus in the 1950s−1970s, which can be seen in all eight tide gauges used for this study. To account for the slowdown period, the acceleration in the basin is investigated by fitting linear trends to time spans of six to seven decades, which include the hiatus. These results imply that the sea level rise is accelerated in the Baltic Sea during the period 1900–2020.

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  • 18.
    Agha Karimi, Armin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Ghobadi-Far, Khosro
    Department of Geosciences, Virginia Tech, Blacksburg, VA, United States.
    Passaro, Marcello
    Deutsches Geodätisches Forschungsinstitut der Technischen Universität München, Munich, Germany.
    Barystatic and steric sea level variations in the Baltic Sea and implications of water exchange with the North Sea in the satellite era2022In: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 9, article id 963564Article in journal (Refereed)
    Abstract [en]

    Satellite altimetry, satellite gravimetry, and in-situ subsurface salinity and temperature profiles are used to investigate the total, barystatic, and steric sea level variations in the Baltic Sea, respectively. To estimate the steric sea level, the density variations are weighted in deeper layers to prevent overestimation of their contribution. We show that the sum of barystatic and steric components exhibits excellent cross correlation (0.9) with satellite altimetry sea level variations and also explains up to 84% of total signal variability from 2002 to 2019. Considering the dominance of barystatic sea level variations in the basin and the limitation of satellite gravimetry in resolving the mass change in water-land transition zones (known as the leakage problem), the mismatch is likely attributed to the inadequate accuracy of the barystatic datasets. The total sea level and its contributors are further decomposed into seasonal, interannual, and decadal temporal components. It is shown that despite its insignificant contributions to seasonal and interannual changes, the steric sea level plays an important role in decadal variations. Additionally, we show that the interannual variations of the barystatic sea level are governed by the North Atlantic Oscillation in the basin. The sea level variation in the North Sea is also examined to deduce the water exchange patterns on different time scales. A drop in the North Sea level can be seen from 2005 to 2011 which is followed by the Baltic Sea level with a ~3-year lag, implying the outflow from the Baltic Sea to the North Sea.

  • 19.
    AghaKouchak, Amir
    et al.
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA; Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA USA.
    Mirchi, Ali
    Oklahoma State Univ, Dept Biosyst & Agr Engn, Stillwater, OK 74078 USA.
    Madani, Kaveh
    Yale Univ, MacMillan Ctr Int & Area Studies, New Haven, CT USA; Stockholm Univ, Dept Phys Geog, Stockholm, Sweden.
    Di Baldassarre, Giuliano
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Nazemi, Ali
    Concordia Univ, Dept Bldg Civil & Environm Engn, Montreal, PQ, Canada.
    Alborzi, Aneseh
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Anjileli, Hassan
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Azarderakhsh, Marzi
    Fairleigh Dickinson Univ, Sch Comp Sci & Engn, Teaneck, NJ USA.
    Chiang, Felicia
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Hassanzadeh, Elmira
    Polytech Montreal, Dept Civil Geol & Min Engn, Montreal, PQ, Canada.
    Huning, Laurie S.
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA; Calif State Univ Long Beach, Dept Civil Engn & Construct Engn Management, Long Beach, CA 90840 USA.
    Mallakpour, Iman
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Martinez, Alexandre
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Mazdiyasni, Omid
    Univ Calif Irvine, Dept Civil & Environm Engn, Irvine, CA 92697 USA.
    Moftakhari, Hamed
    Univ Alabama, Dept Civil Construct & Environm Engn, Tuscaloosa, AL USA.
    Norouzi, Hamid
    CUNY, New York City Coll Technol, Brooklyn, NY 11210 USA.
    Sadegh, Mojtaba
    Boise State Univ, Dept Civil Engn, Boise, ID 83725 USA.
    Sadeqi, Dalal
    Kuwait Inst Sci Res, Water Res Ctr, Kuwait, Kuwait.
    Van Loon, Anne F.
    Vrije Univ Amsterdam, Inst Environm Studies, Amsterdam, Netherlands.
    Wanders, Niko
    Univ Utrecht, Fac Geosci, Dept Phys Geog, Utrecht, Netherlands.
    Anthropogenic Drought: Definition, Challenges, and Opportunities2021In: Reviews of geophysics, ISSN 8755-1209, E-ISSN 1944-9208, Vol. 59, no 2, article id e2019RG000683Article, review/survey (Refereed)
    Abstract [en]

    Traditional, mainstream definitions of drought describe it as deficit in water-related variables or water-dependent activities (e.g., precipitation, soil moisture, surface and groundwater storage, and irrigation) due to natural variabilities that are out of the control of local decision-makers. Here, we argue that within coupled human-water systems, drought must be defined and understood as a process as opposed to a product to help better frame and describe the complex and interrelated dynamics of both natural and human-induced changes that define anthropogenic drought as a compound multidimensional and multiscale phenomenon, governed by the combination of natural water variability, climate change, human decisions and activities, and altered micro-climate conditions due to changes in land and water management. This definition considers the full spectrum of dynamic feedbacks and processes (e.g., land-atmosphere interactions and water and energy balance) within human-nature systems that drive the development of anthropogenic drought. This process magnifies the water supply demand gap and can lead to water bankruptcy, which will become more rampant around the globe in the coming decades due to continuously growing water demands under compounding effects of climate change and global environmental degradation. This challenge has de facto implications for both short-term and long-term water resources planning and management, water governance, and policymaking. Herein, after a brief overview of the anthropogenic drought concept and its examples, we discuss existing research gaps and opportunities for better understanding, modeling, and management of this phenomenon.

    Plain Language Summary

    This article reviews research and progress on the notion of anthropogenic drought broadly defined as drought events caused or intensified by human activities. Most commonly used drought definitions are based on deficit in hydrologic/meteorologic drivers such as precipitation and runoff. Within coupled human-water systems, however, drought must be defined and understood as the complex and interrelated dynamics of both natural and human-induced changes. This anthropogenic drought definition considers the full spectrum of dynamic feedbacks and processes (e.g., land-atmosphere interactions and water and energy balance) within human-nature systems. Ideally, anthropogenic drought and the corresponding human interactions should be incorporated in models that include land-atmosphere interactions, water balance, and energy balance. In this article, we review existing research gaps and opportunities for better understanding, modeling, and management of this phenomenon.

  • 20.
    Ahlberg, Jesper
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Distributed snow modelling integrating ground penetrating radar data for improved runoff predictions in a Swedish mountain basin2009In: EGU General Assembly 2009, 2009Conference paper (Other academic)
    Abstract [en]

    Operational forecasts of snow melt runoff in Sweden are currently running with precipitation and temperature as the main input variables and calibrated with runoff data, and there is an interest to make better use of new measurement systems for distributed snow data. At the same time, various data assimilation techniques are becoming more frequently used in hydrological modeling, in order to reduce uncertainties related to both model structure errors and errors in input and calibration data. Thus, it is important to address not only what type of snow data that can be used to improve the model predictions, but also what type of input data and model structures that are optimal in relation to the available snow data. The objective of this study is to investigate to what extent the runoff predictions can be improved by assimilation of temporal and spatially distributed snow data, and if the improvements depend on the choice of model structures, for instance the use of energy balance or day-degree snow models. In order to achieve these objectives a new distributed snow model has been implemented into the hydrological modeling framework HYSS/HYPE. This model can easily be setup with either an energy balance model or a day-degree model for the snow pack calculations, and it is easy to run the model with different spatial resolutions. In the fully distributed case, snow drift processes are implicitly included in the model through a precipitation distribution model, based on topographical information and wind direction. The model was applied to a mountain basin in northern Sweden used for hydropower production, where extensive snow measurements were taken during the last two winters 2007-2009. A climate station is located at the outlet of the regulation lake, including automated point measurements of snow depth, snow mass (snow pillow), snow wetness and snow temperature. Distributed snow cover data was sampled using ground-penetrating radar from snow mobiles. Measurements were taken at the time of the maximum snow cover, providing a data set with snow depth, snow density, snow water equivalent along 20 km long transects in representative areas of the basin. The precipitation distribution model was calibrated using the distributed SWE data from the GPR measurements. Application of the calibrated model to previous years without available snow data show that the runoff predictions was improved compared to calibrations without the distributed snow data, however the improvements were larger for the energy balance compared to the day-degree model. Further developments will include assimilation of the temporal and spatial snow data to adjust the distribution of various input variables, for instance air temperature and wind speed.

  • 21.
    Ahlberg, Jesper
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Snow melt runoff simulations using ensemble Kalman filter assimilation of distributed snow data2010Conference paper (Other academic)
  • 22. Ahlers, R.
    et al.
    Cleaver, F
    Rusca, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Schwartz, K.
    Unleashing Entrepreneurs or Controlling Unruly Providers?: The Formalisation of Small-scale Water Providers in Greater Maputo, Mozambique2013In: Journal of Development Studies, ISSN 0022-0388, E-ISSN 1743-9140, Vol. 49, no 4, p. 470-482Article in journal (Refereed)
    Abstract [en]

    The existing legal and policy framework regulating water service provision in Greater Maputo, Mozambique appears fixated on the official service areas. In doing so it inadequately addresses the geographically varied service provision modalities which characterise the city. We argue that the predominant legal and policy framework does little to support development of improved services in areas unserved by the formal utility. Although ad hoc measures recognising small-scale providers as a temporary alternative to service provision by a formal utility have been implemented, these measures appear designed to increase control over these providers rather than support the service delivery capacity of small-scale providers.

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  • 23.
    Ahlgren, Joakim
    et al.
    Umeå University, Faculty of Science and Technology, Umeå Marine Sciences Centre (UMF). The Swedish Institute for the Marine Environment, PO Box 260, SE-40530 Göteborg, Sweden.
    Grimvall, Anders
    Omstedt, Anders
    Rolff, Carl
    Wikner, Johan
    Umeå University, Faculty of Science and Technology, Umeå Marine Sciences Centre (UMF). The Swedish Institute for the Marine Environment, PO Box 260, SE-40530 Göteborg, Sweden.
    Temperature, DOC level and basin interactions explain the declining oxygen concentrations in the Bothnian Sea2017In: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 170, p. 22-30Article in journal (Refereed)
    Abstract [en]

    Hypoxia and oxygen deficient zones are expanding worldwide. To properly manage this deterioration of the marine environment, it is important to identify the causes of oxygen declines and the influence of anthropogenic activities. Here, we provide a study aiming to explain the declining oxygen levels in the deep waters of the Bothnian Sea over the past 20 years by investigating data from environmental monitoring programmes. The observed decline in oxygen concentrations in deep waters was found to be primarily a consequence of water temperature increase and partly caused by an increase in dissolved organic carbon (DOC) in the seawater (R-Adj(2). = 0.83) as well as inflow from the adjacent sea basin. As none of the tested eutrophication-related predictors were significant according to a stepwise multiple regression, a regional increase in nutrient inputs to the area is unlikely to explain a significant portion of the oxygen decline. Based on the findings of this study, preventing the development of anoxia in the deep water of the Bothnian Sea is dependent on the large-scale measures taken to reduce climate change. In addition, the reduction of the nutrient load to the Baltic Proper is required to counteract the development of hypoxic and phosphate-rich water in the Baltic Proper, which can form deep water in the Bothnian Sea. The relative importance of these sources to oxygen consumption is difficult to determine from the available data, but the results clearly demonstrate the importance of climate related factors such as temperature, DOC and inflow from adjacent basins for the oxygen status of the sea.

  • 24.
    Ahlinder, Jon
    et al.
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Eriksson, Karolina Ida Anna
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Hellmér, Maria
    Department of Biology, Science Division, Swedish Food Agency, Sweden.
    Salomonsson, Emelie
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Granberg, Malin
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Dacklin, Ingrid
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Elving, Josefine
    Department of Chemistry, Environment and Feed Hygiene, National Veterinary Institute, Sweden.
    Brindefalk, Björn
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Upstream land use with microbial downstream consequences: iron and humic substances link to Legionella spp.Manuscript (preprint) (Other academic)
  • 25.
    Ahlinder, Jon
    et al.
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden; Department of Tree Breeding, Skogforsk, Sävar, Sweden.
    Eriksson, Karolina Ida Anna
    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).
    Hellmér, Maria
    Department of Biology, Science Division, Swedish Food Agency, Sweden.
    Salomonsson, Emelie
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Granberg, Malin
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Dacklin, Ingrid
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden.
    Elving, Josefine
    Department of Chemistry, Environment and Feed Hygiene, Swedish Veterinary Agency, Sweden.
    Brindefalk, Björn
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI), Sweden; Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden.
    Upstream land use with microbial downstream consequences: iron and humic substances link to Legionella spp2024In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 256, article id 121579Article in journal (Refereed)
    Abstract [en]

    Intensified land use can disturb water quality, potentially increasing the abundance of bacterial pathogens, threatening public access to clean water. This threat involves both direct contamination of faecal bacteria as well as indirect factors, such as disturbed water chemistry and microbiota, which can lead to contamination. While direct contamination has been well described, the impact of indirect factors is less explored, despite the potential of severe downstream consequences on water supply. To assess direct and indirect downstream effects of buildings, farms, pastures and fields on potential water sources, we studied five Swedish lakes and their inflows. We analysed a total of 160 samples in a gradient of anthropogenic activity spanning four time points, including faecal and water-quality indicators. Through species distribution modelling, Random Forest and network analysis using 16S rRNA amplicon sequencing data, our findings highlight that land use indirectly impacts lakes via inflows. Land use impacted approximately one third of inflow microbiota taxa, in turn impacting ∌20–50 % of lake taxa. Indirect effects via inflows were also suggested by causal links between e.g. water colour and lake bacterial taxa, where this influenced the abundance of several freshwater bacteria, such as Polynucleobacter and Limnohabitans. However, it was not possible to identify direct effects on the lakes based on analysis of physiochemical- or microbial parameters. To avoid potential downstream consequences on water supply, it is thus important to consider possible indirect effects from upstream land use and inflows, even when no direct effects can be observed on lakes. Legionella (a genus containing bacterial pathogens) illustrated potential consequences, since the genus was particularly abundant in inflows and was shown to increase by the presence of pastures, fields, and farms. The approach presented here could be used to assess the suitability of lakes as alternative raw water sources or help to mitigate contaminations in important water catchments. Continued broad investigations of stressors on the microbial network can identify indirect effects, avoid enrichment of pathogens, and help secure water accessibility.

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  • 26.
    Ahlkrona, Malva
    SMHI.
    Phospherous in a Biogeochemical Lake Model2002Report (Other academic)
    Abstract [en]

    BIOLA isa biogeochemical lake model within the V ASTRA research programme. The model's

    main purpose is to predict the ecological responses to changed nutrient loads. The phosphorus simulations were not satisfactory and the sediment was thought to be the critical part. The aim of this work was to improve the phosphorus simulations. Therefore a new sediment approach has been developed. Three main changes of the sediment processes were carried through:

    • Resuspension of sediments from erosion and transportation bottoms was added

    • The sediments were divided into an upper, aerobic, and a lower, anaerobic, layer

    • The relation between sorbed and dissolved phosphorus in the sediments was described by

    Langmuir isotherms, with a sorption 2.5 times higher at aerobic compared to anaerobic

    conditions

    The modelling of total phosphorus and blue-green algae was improved. Especially the timing of high concentration peaks was much better. One problem still lingering is the modelled oxygen levels, which were much higher than the observed levels. Therefore the model has not been tested for anaerobic conditions. A verage release rates from the sediments were 2.5 mg Pa-1 <luring the summer, which is reasonable. A 20-year simulation of step-response was run with increased and decreased nutrient loads. Roughly four years after the change, the model had reached a new equilibrium.

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  • 27.
    Ahlstedt, Oskar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    How variations of the duration and time to peak of the Chicago Design Storm affect the hydraulic response, as well as the areas contributing to peak runoff, of a synthetic urban catchment area2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With an expanding urbanization in the world, and thus the expansion of impermeable surfaces, the risk of pluvial floods is an increasing factor that needs to be considered. This, in combination with increasing rain intensities and frequency of rain events indicates a problem both today and for the future. With this in mind, it is an advantage to increase the knowledge of how different variations of extreme rainfall affects the hydraulic response of urban catchments, as well as which areas in urban environments contribute to the flood peak.

    The aims of this study are, with a particle tracking approach, to investigate how the peak runoff contributing areas differ geographically depending on the duration and time to peak of the rainfall event. This also includes the evaluation of what sizes of urban catchment areas are relevant to include when modelling the hydraulic response of Swedish urban catchment in relation to the characteristics of the hyetograph. The catchment area used in this study is made synthetically to represent a generic Swedish urban catchment with regards to the proportions of hardened surfaces, buildings and low points, as well as the slope of the catchment. Various variants of the Chicago Design Storm were implemented in the model. This included three different durations of 2-, 4- and 6 hours of which each, separately, constituted of three different time to peak that is decided by an r-value when creating the design storms. The r-values used in this study is 0.1, 0.4 and 0.8 where the values correlates to an early-, centred- and late peak of the hyetograph. To be able to investigate the peak contributing area, a particle tracking approach was initially used as an equivalent to tracers where the particles are first evenly distributed over the catchment area to then be concentrated to the locations that shows a variation in in the peak contributing area. This was done by using the modelling program MIKE 21 Flow Model FM powered by DHI, which also was used to run the hydrodynamic simulations of the inundation.

    The results of the hydrodynamic simulations showed that the rain events generated more runoff as the duration was extended. In addition, the timing of the peak of the rainfall intensity also had an impact on the result as the runoff increased with increasing r-value. Thus, as the peak of the hyetograph is delayed, it imposes an increasing risk of severe flooding. Furthermore, with the use of particle tracking, it could be concluded that the different design storm had an influence on the peak contributing distance where the distance grew larger when the duration of the rainfall event was extended and when the peak of the storm was delayed.

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  • 28.
    Ahlström, Hanna
    et al.
    Royal Swedish Acad Sci, Global Econ Dynam & Biosphere, POB 50005, SE-10405 Stockholm, Sweden..
    Hileman, Jacob
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Government.
    Wang-Erlandsson, Lan
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, Stockholm, Sweden..
    Garcia, Maria Mancilla
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden.;Univ Libre Bruxelles ULB, Fac Sci, Socioenvironm Dynam Res Grp SONYA, Brussels, Belgium..
    Moore, Michele-Lee
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden.;Univ Victoria, Dept Geog, Victoria, BC, Canada.;Univ Victoria, Ctr Global Studies, Victoria, BC, Canada..
    Jonas, Krisztina
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden..
    Pranindita, Agnes
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, Stockholm, Sweden..
    Kuiper, Jan J.
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden..
    Fetzer, Ingo
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden..
    Jaramillo, Fernando
    Stockholm Univ, Bolin Ctr Climate Res, Stockholm, Sweden.;Stockholm Univ, Dept Phys Geog, Stockholm, Sweden..
    Svedin, Uno
    Stockholm Univ, Stockholm Resilience Ctr, Stockholm, Sweden..
    An Earth system law perspective on governing social-hydrological systems in the Anthropocene2021In: Earth System Governance, ISSN 2589-8116, Vol. 10, article id 100120Article in journal (Refereed)
    Abstract [en]

    The global hydrological cycle is characterized by complex interdependencies and self-regulating feedbacks that keep water in an ever-evolving state of flux at local, regional, and global levels. Increasingly, the scale of human impacts in the Anthropocene is altering the dynamics of this cycle, which presents additional challenges for water governance. "Earth system law" provides an important approach for addressing gaps in governance that arise from the mismatch between the global hydrological cycle and dispersed regulatory architecture across institutions and geographic regions. In this article, we articulate the potential for Earth system law to account for core hydrological problems that complicate water governance, including delay, redistribution, intertwinements, permanence, and scale. Through merging concepts from Earth system law with existing policy and legal principles, we frame an approach for addressing hydrological problems in the Anthropocene and strengthening institutional fit between established governance systems and the global hydrological cycle. We discuss how such an approach can be applied, and the challenges and implications for governing water as a cycle and complex social-hydrological system, both in research and practice.

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  • 29.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering. SIBELCO Ankerpoort NV, Op Bos 300, NL-6223 EP Maastricht, Netherlands.;Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Global Groundwater: Source, Scarcity, Security and Solutions2021In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 15, article id 100605Article, book review (Other academic)
  • 30. Ahmed, Mohamed Ismaiel
    et al.
    Shook, Kevin
    Pietroniro, Alain
    Stadnyk, Tricia
    Pomeroy, John W.
    Pers, Charlotta
    SMHI, Research Department, Hydrology.
    Gustafsson, David
    SMHI, Research Department, Hydrology.
    Implementing a parsimonious variable contributing area algorithm for the prairie pothole region in the HYPE modelling framework2023In: Environmental Modelling & Software, ISSN 1364-8152, E-ISSN 1873-6726, Vol. 167, article id 105769Article in journal (Refereed)
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    Implementing a parsimonious variable contributing area algorithm for the prairie pothole region in the HYPE modelling framework
  • 31.
    Ahmed, Rafiq
    Linköping University, The Tema Institute, Department of Water and Environmental Studies.
    Seasonal Variation of Inorganic Nutrients (DSi, DIN and DIP) Concentration in Swedish River2007Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
    Abstract [en]

    Rivers have been playing most important role as fresh water source and medium of nutrient transportation from terrestrial to aquatic ecosystem. Inorganic form of nutrients (DSi, DIN and DIP) are plant available mostly control the productivity of aquatic ecosystem. Transfer of these nutrients in higher concentrations cause harmful eutrophication in receiving water body.

    Study of dissolved inorganic nutrients concentrations in 12 Swedish rivers of different basin characteristics demonstrated both similar and varying behaviour from river to river and from season to season depending on catchment hydrology; land use and geology. Highest concentration did not coincide with the highest runoff. High DSi concentration observed in the unperturbed rivers however, high DIN and DIP concentration observed in agriculture dominated river followed by river basin dominated by industrial and urban activities. DSi and DIN concentration observed high in winter and decreased through spring to reach lowest in summer. DIP concentration although found low in summer but high concentration observed in early spring and early autumn. Rivers with low average runoff positively correlated with DSi and DIN concentration however, DIP demonstrated weak correlation.

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  • 32.
    Ahmerkamp, Soeren
    et al.
    Max Planck Inst Marine Microbiol, D-28359 Bremen, Germany..
    Jalaluddin, Farooq Moin
    Max Planck Inst Marine Microbiol, D-28359 Bremen, Germany..
    Cui, Yuan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Physiology and Environmental Toxicology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Brumley, Douglas R.
    Univ Melbourne, Sch Math & Stat, Parkville, Vic 3010, Australia..
    Pacherres, Cesar O.
    Alfred Wegener Inst, Helmholtz Ctr Polar & Marine Res, Bremerhaven, Germany.;Univ Copenhagen, Dept Biol, Copenhagen, Denmark..
    Berg, Jasmine S.
    Univ Lausanne, Inst Earth Surface Dynam, CH-1015 Lausanne, Switzerland..
    Stocker, Roman
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, CH-8093 Zurich, Switzerland..
    Kuypers, Marcel M. M.
    Max Planck Inst Marine Microbiol, D-28359 Bremen, Germany..
    Koren, Klaus
    Aarhus Univ, Ctr Water Technol, Dept Biol, DK-8000 Aarhus, Denmark..
    Behrendt, Lars
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Physiology and Environmental Toxicology.
    Simultaneous visualization of flow fields and oxygen concentrations to unravel transport and metabolic processes in biological systems2022In: CELL REPORTS METHODS, ISSN 2667-2375, Vol. 2, no 5, article id 100216Article in journal (Refereed)
    Abstract [en]

    From individual cells to whole organisms, O-2 transport unfolds across micrometer- tomillimeter-length scales and can change within milliseconds in response to fluid flows and organismal behavior. The spatiotemporal complexity of these processes makes the accurate assessment of O-2 dynamics via currently availablemethods difficult or unreliable. Here, we present "sensPIV,'' a method to simultaneously measure O-2 concentrations and flow fields. By tracking O-2-sensitive microparticles in flow using imaging technologies that allow for instantaneous referencing, wemeasuredO(2) transportwithin (1) microfluidic devices, (2) sinkingmodel aggregates, and (3) complex colony-forming corals. Through the use of sensPIV, we find that corals use ciliarymovement to link zones of photosynthetic O-2 production to zones of O-2 consumption. SensPIV can potentially be extendable to study flow-organism interactions across many life-science and engineering applications.

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  • 33. Aho, Kelly S.
    et al.
    Fair, Jennifer H.
    Hosen, Jacob D.
    Kyzivat, Ethan D.
    Logozzo, Laura A.
    Rocher-Ros, Gerard
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Umeå University, Arctic Research Centre at Umeå University.
    Weber, Lisa C.
    Yoon, Byungman
    Raymond, Peter A.
    Distinct concentration-discharge dynamics in temperate streams and rivers: CO2 exhibits chemostasis while CH4 exhibits source limitation due to temperature control2021In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 66, no 10, p. 3656-3668Article in journal (Refereed)
    Abstract [en]

    Streams and rivers are significant sources of carbon dioxide (CO2) and methane (CH4) to the atmosphere. However, the magnitudes of these fluxes are uncertain, in part, because dissolved greenhouse gases (GHGs) can exhibit high spatiotemporal variability. Concentration-discharge (C-Q) relationships are commonly used to describe temporal variability stemming from hydrologic controls on solute production and transport. This study assesses how the partial pressures of two GHGs—pCO2 and pCH4—vary across hydrologic conditions over 4 yr in eight nested streams and rivers, at both annual and seasonal timescales. Overall, the range of pCO2 was constrained, ranging from undersaturated to nine times oversaturated, while pCH4 was highly variable, ranging from 3 to 500 times oversaturated. We show that pCO2 exhibited chemostatic behavior (i.e., no change with Q), in part, due to carbonate buffering and seasonally specific storm responses. In contrast, we show that pCH4 generally exhibited source limitation (i.e., a negative relationship with Q), which we attribute to temperature-mediated production. However, pCH4 exhibited chemostasis in a wetland-draining stream, likely due to hydrologic connection to the CH4-rich wetland. These findings have implications for CO2 and CH4 fluxes, which are controlled by concentrations and gas transfer velocities. At high Q, enhanced gas transfer velocity acts on a relatively constant CO2 stock but on a diminishing CH4 stock. In other words, CO2 fluxes increase with Q, while CH4 fluxes are modulated by the divergent Q dynamics of gas transfer velocity and concentration.

  • 34. Aich, Valentin
    et al.
    Liersch, Stefan
    Vetter, Tobias
    Andersson, Jafet
    SMHI, Research Department, Hydrology.
    Mueller, Eva N.
    Hattermann, Fred F.
    Climate or Land Use?-Attribution of Changes in River Flooding in the Sahel Zone2015In: Water, E-ISSN 2073-4441, Vol. 7, no 6, p. 2796-2820Article in journal (Refereed)
    Abstract [en]

    This study intends to contribute to the ongoing discussion on whether land use and land cover changes (LULC) or climate trends have the major influence on the observed increase of flood magnitudes in the Sahel. A simulation-based approach is used for attributing the observed trends to the postulated drivers. For this purpose, the ecohydrological model SWIM (Soil and Water Integrated Model) with a new, dynamic LULC module was set up for the Sahelian part of the Niger River until Niamey, including the main tributaries Sirba and Goroul. The model was driven with observed, reanalyzed climate and LULC data for the years 1950-2009. In order to quantify the shares of influence, one simulation was carried out with constant land cover as of 1950, and one including LULC. As quantitative measure, the gradients of the simulated trends were compared to the observed trend. The modeling studies showed that for the Sirba River only the simulation which included LULC was able to reproduce the observed trend. The simulation without LULC showed a positive trend for flood magnitudes, but underestimated the trend significantly. For the Goroul River and the local flood of the Niger River at Niamey, the simulations were only partly able to reproduce the observed trend. In conclusion, the new LULC module enabled some first quantitative insights into the relative influence of LULC and climatic changes. For the Sirba catchment, the results imply that LULC and climatic changes contribute in roughly equal shares to the observed increase in flooding. For the other parts of the subcatchment, the results are less clear but show, that climatic changes and LULC are drivers for the flood increase; however their shares cannot be quantified. Based on these modeling results, we argue for a two-pillar adaptation strategy to reduce current and future flood risk: Flood mitigation for reducing LULC-induced flood increase, and flood adaptation for a general reduction of flood vulnerability.

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  • 35. Aich, Valentin
    et al.
    Liersch, Stefan
    Vetter, Tobias
    Fournet, Samuel
    Andersson, Jafet
    SMHI, Research Department, Hydrology.
    Calmanti, Sandro
    van Weert, Frank H. A.
    Hattermann, Fred F.
    Paton, Eva N.
    Flood projections within the Niger River Basin under future land use and climate change2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 562, p. 666-677Article in journal (Refereed)
    Abstract [en]

    This study assesses future flood risk in the Niger River Basin (NRB), for the first time considering the simultaneous effects of both projected climate change and land use changes. For this purpose, an ecohydrological process-based model (SWIM) was set up and validated for past climate and land use dynamics of the entire NRB. Model runs for future flood risks were conducted with an ensemble of 18 climate models, 13 of them dynamically downscaled from the CORDEX Africa project and five statistically downscaled Earth System Models. Two climate and two land use change scenarios were used to cover a broad range of potential developments in the region. Two flood indicators (annual 90th percentile and the 20-year return flood) were used to assess the future flood risk for the Upper, Middle and Lower Niger as well as the Benue. The modeling results generally show increases of flood magnitudes when comparing a scenario period in the near future (2021-2050) with a base period (1976-2005). Land use effects are more uncertain, but trends and relative changes for the different catchments of the NRB seem robust. The dry areas of the Sahelian and Sudanian regions of the basin show a particularly high sensitivity to climatic and land use changes, with an alarming increase of flood magnitudes in parts. A scenario with continuing transformation of natural vegetation into agricultural land and urbanization intensifies the flood risk in all parts of the NRB, while a "regreening" scenario can reduce flood magnitudes to some extent. Yet, land use change effects were smaller when compared to the effects of climate change. In the face of an already existing adaptation deficit to catastrophic flooding in the region, the authors argue for a mix of adaptation and mitigation efforts in order to reduce the flood risk in the NRB. (C) 2016 Elsevier B.V. All rights reserved.

  • 36. Akam, Sajjad A.
    et al.
    Swanner, Elizabeth D.
    Yao, Hongming
    Hong, Wei-Li
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Peckmann, Jörn
    Methane-derived authigenic carbonates – A case for a globally relevant marine carbonate factory2023In: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 243, article id 104487Article in journal (Refereed)
    Abstract [en]

    Precipitation of methane-derived authigenic carbonates (MDAC) is an integral part of marine methane production and consumption, but MDAC's relative significance to the global marine carbon cycle is not well understood. Here we provide a synthesis and perspective to highlight MDAC from a global marine carbon biogeochemistry viewpoint. MDAC formation is a result and archive of carbon‑sulfur (C S) coupling in the shallow sulfatic zone and carbon‑silicon (C Si) coupling in deeper methanic sediments. MDAC constitute a carbon sequestration of 3.93 Tmol C yr−1 (range 2.34–5.8 Tmol C yr−1) in the modern ocean and are the third-largest carbon burial mechanism in marine sediments. This burial compares to 29% (11–57%) organic carbon and 10% (6–23%) skeletal carbonate carbon burial along continental margins. MDAC formation is also an important sink for benthic alkalinity and, thereby, a potential contributor to bottom water acidification. Our understanding of the impact of MDAC on global biogeochemical cycles has evolved over the past five decades from what was traditionally considered a passive carbon sequestration mechanism in a seep-oasis setting to what is now considered a dynamic carbonate factory expanding from deep sediments to bottom waters—a factory that has been operational since the Precambrian. We present a strong case for the need to improve regional scale quantification of MDAC accumulation rates and associated carbonate biogeochemical parameters, leading to their incorporation in present and paleo‑carbon budgets in the next phase of MDAC exploration.

  • 37.
    Akhoudas, Camille Hayatte
    et al.
    Stockholm University, Faculty of Science, Department of Geological Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Sallée, Jean-Baptiste
    Reverdin, Gilles
    Haumann, F. Alexander
    Pauthenet, Etienne
    Chapman, Christopher C.
    Margirier, Félix
    Lo Monaco, Claire
    Metzl, Nicolas
    Meilland, Julie
    Stranne, Christian
    Stockholm University, Faculty of Science, Department of Geological Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Isotopic evidence for an intensified hydrological cycle in the Indian sector of the Southern Ocean2023In: Nature Communications, E-ISSN 2041-1723, Vol. 14, article id 2763Article in journal (Refereed)
    Abstract [en]

    The hydrological cycle is expected to intensify in a warming climate. However, observational evidence of such changes in the Southern Ocean is difficult to obtain due to sparse measurements and a complex superposition of changes in precipitation, sea ice, and glacial meltwater. Here we disentangle these signals using a dataset of salinity and seawater oxygen isotope observations collected in the Indian sector of the Southern Ocean. Our results show that the atmospheric water cycle has intensified in this region between 1993 and 2021, increasing the salinity in subtropical surface waters by 0.06 ± 0.07 g kg−1 per decade, and decreasing the salinity in subpolar surface waters by -0.02 ± 0.01 g kg−1 per decade. The oxygen isotope data allow to discriminate the different freshwater processes showing that in the subpolar region, the freshening is largely driven by the increase in net precipitation (by a factor two) while the decrease in sea ice melt is largely balanced by the contribution of glacial meltwater at these latitudes. These changes extend the growing evidence for an acceleration of the hydrological cycle and a melting cryosphere that can be expected from global warming.

  • 38. Akhtar, Naveed
    et al.
    Krug, Amelie
    Brauch, Jennifer
    Arsouze, Thomas
    Dieterich, Christian
    SMHI, Research Department, Oceanography.
    Ahrens, Bodo
    European marginal seas in a regional atmosphere-ocean coupled model and their impact on Vb-cyclones and associated precipitation2019In: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 53, no 9-10, p. 5967-5984Article in journal (Refereed)
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  • 39.
    Akhter, Firoza
    et al.
    KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, S-10046 Stockholm, Sweden..
    Mazzoleni, Maurizio
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Ctr Nat Hazards & Disaster Sci CNDS, S-75236 Uppsala, Sweden..
    Brandimarte, Luigia
    KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, S-10046 Stockholm, Sweden..
    Analysis of 220 Years of Floodplain Population Dynamics in the US at Different Spatial Scales2021In: Water, E-ISSN 2073-4441, Vol. 13, no 2, article id 141Article in journal (Refereed)
    Abstract [en]

    In this study, we explore the long-term trends of floodplain population dynamics at different spatial scales in the contiguous United States (U.S.). We exploit different types of datasets from 1790-2010-i.e., decadal spatial distribution for the population density in the US, global floodplains dataset, large-scale data of flood occurrence and damage, and structural and nonstructural flood protection measures for the US. At the national level, we found that the population initially settled down within the floodplains and then spread across its territory over time. At the state level, we observed that flood damages and national protection measures might have contributed to a learning effect, which in turn, shaped the floodplain population dynamics over time. Finally, at the county level, other socio-economic factors such as local flood insurances, economic activities, and socio-political context may predominantly influence the dynamics. Our study shows that different influencing factors affect floodplain population dynamics at different spatial scales. These facts are crucial for a reliable development and implementation of flood risk management planning.

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  • 40. Akselsson, Cecilia
    et al.
    Olsson, Jonas
    SMHI, Research Department, Hydrology.
    Belyazid, Salim
    Capell, Réne
    SMHI, Research Department, Hydrology.
    Can increased weathering rates due to future warming compensate for base cation losses following whole-tree harvesting in spruce forests?2016In: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 128, no 1-2, p. 89-105Article in journal (Refereed)
  • 41.
    Al Mousawi, Eman
    et al.
    Department of Civil Engineering, Faculty of Engineering, University of Babylon, Hillah, Babylon 51001, Iraq.
    Jahad, Udai Adnain
    Department of Environment Engineering, Faculty of Engineering, University of Babylon, Hillah, Babylon 51001, Iraq.
    Chabuk, Ali
    Department of Environment Engineering, College of Engineering, University of Babylon, Babylon 51001, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Majdi, Ali
    Building and Construction Techniques Engineering, Al-Mustaqbal University College, 51001, Babylon, Iraq.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Applying Different Water Quality Indices and GIS to Assess the Water Quality, Case Study: Euphrates River in Qadisiyah Province2023In: Polish Journal of Environmental Studies, ISSN 1230-1485, E-ISSN 2083-5906, Vol. 32, no 5, p. 4201-4217Article in journal (Refereed)
    Abstract [en]

    A well-known tool for assessing the quality of surface water is the water quality index (WQI) model. In this study, the WQI was generated to classify the water flowing in the Euphrates River in Qadisiyah Province. To develop analytical models, a connection between the findings and satellite images was developed. It is possible to determine what category a river’s water quality for domestic use will fall into. The Weighted Arithmetic Water Quality Index (WWQI), Canadian Water Quality Index (CWQI),and Bascarón Water Quality Index (BWQI) were used to evaluate and examine the suitability of the Euphrates River in the city by analysing the water quality of samples taken from the five locations (Muhanawia (L1), Salahia (L2), Shamiyah (L3), Shamiyah (L4), Gammas (L5)). The hydrogen ionspH, temperature T, dissolved oxygen DO, nitrate NO3, calcium Ca, magnesium Mg, total hardness TH, potassium K, sodium Na, sulfate SO4, chlorine Cl, total dissolved solids TDS, and electrical conductivity ECvalues are provided for 2020 and 2021. Results showed the Euphrates River was deemed severely contaminated at location Gammas (L5) but acceptable at location Muhanawia (L1). During the research phase, the water quality for the Euphrates achieved a maximum of 87.43 using the CWQI for Muhanawia (L1) in 2021 and a minimum of 15.6 using the BWQI for Gammas (L5) in 2021. The excessive sulphate, total dissolved solids, calcium, and total hardness concentrations led to the low WQI. The results are analysed using a GIS, and a network database connected to the GIS is required to utilize its analytical capabilities and the geographically scattered data throughout the study region. The Water Quality Index (WQI) is not suitable for drinking, as it is below the average of the World Health Organization (WHO) suggestions.

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  • 42. Ala-aho, P.
    et al.
    Soulsby, C.
    Pokrovsky, O. S.
    Kirpotin, S. N.
    Karlsson, Jan
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Serikova, Svetlana
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Manasypov, R.
    Lim, A.
    Krickov, I.
    Kolesnichenko, L. G.
    Laudon, H.
    Tetzlaff, D.
    Permafrost and lakes control river isotope composition across a boreal Arctic transect in the Western Siberian lowlands2018In: Environmental Research Letters, E-ISSN 1748-9326, Vol. 13, no 3, p. =20-=20, article id 034028Article in journal (Refereed)
    Abstract [en]

    The Western Siberian Lowlands (WSL) store large quantities of organic carbon that will be exposed and mobilized by the thawing of permafrost. The fate of mobilized carbon, however, is not well understood, partly because of inadequate knowledge of hydrological controls in the region which has a vast low-relief surface area, extensive lake and wetland coverage and gradually increasing permafrost influence. We used stable water isotopes to improve our understanding of dominant landscape controls on the hydrology of the WSL. We sampled rivers along a 1700 km South-North transect from permafrost-free to continuous permafrost repeatedly over three years, and derived isotope proxies for catchment hydrological responsiveness and connectivity. We found correlations between the isotope proxies and catchment characteristics, suggesting that lakes and wetlands are intimately connected to rivers, and that permafrost increases the responsiveness of the catchment to rainfall and snowmelt events, reducing catchment mean transit times. Our work provides rare isotope-based field evidence that permafrost and lakes/wetlands influence hydrological pathways across a wide range of spatial scales (10-105 km2) and permafrost coverage (0%-70%). This has important implications, because both permafrost extent and lake/wetland coverage are affected by permafrost thaw in the changing climate. Changes in these hydrological landscape controls are likely to alter carbon export and emission via inland waters, which may be of global significance.

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  • 43. Ala-aho, P.
    et al.
    Soulsby, C.
    Pokrovsky, O. S.
    Kirpotin, S. N.
    Karlsson, Jan
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Serikova, Svetlana
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Vorobyev, S. N.
    Manasypov, R. M.
    Loiko, S.
    Tetzlaff, D.
    Using stable isotopes to assess surface water source dynamics and hydrological connectivity in a high-latitude wetland and permafrost influenced landscape2018In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 556, p. 279-293Article in journal (Refereed)
    Abstract [en]

    Climate change is expected to alter hydrological and biogeochemical processes in high-latitude inland waters. A critical question for understanding contemporary and future responses to environmental change is how the spatio-temporal dynamics of runoff generation processes will be affected. We sampled stable water isotopes in soils, lakes and rivers on an unprecedented spatio-temporal scale along a 1700 km transect over three years in the Western Siberia Lowlands. Our findings suggest that snowmelt mixes with, and displaces, large volumes of water stored in the organic soils and lakes to generate runoff during the thaw season. Furthermore, we saw a persistent hydrological connection between water bodies and the landscape across permafrost regions. Our findings help to bridge the understanding between small and large scale hydrological studies in high-latitude systems. These isotope data provide a means to conceptualise hydrological connectivity in permafrost and wetland influenced regions, which is needed for an improved understanding of future biogeochemical changes.

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  • 44.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hydro-politics of Water Resources in Iraq2022In: Proceedings of the 39th IAHR World Congress: From Snow To Sea / [ed] Miguel Ortega-Sánchez, International Association for Hydro-Environment Engineering and Research (IAHR) , 2022, p. 2960-2968Conference paper (Refereed)
    Abstract [en]

    Iraq relies in its water resources on the Tigris and Euphrates and their tributaries. It is located at the lower part of the catchment area of these rivers. The long-term average annual flow that enter Iraq is about 30 BCM from the Euphrates, 22.2 BCM from the Tigris, 24.78BCM from tributaries and 7BCM from side valleys between Iraq and Iran. Now, the flow of these rivers is decreasing due to climate change and hydrological projects established in the upper parts of the catchment. Precipitation will decrease 15-25% during this century and the flow of the Tigris and Euphrates Rivers will be reduced by 29-73%. This will cause a grave depletion of ground water resources. Turkey is trying to build 22 dams and 19 hydropower stations. Iran built 12 dams, diverted the flow of some tributaries inside Iran, and blocked all the valleys that contributes water from its land to Iraq. The factors affecting the hydro politics within these basin are: Water scarcity, Climate change and Hydrological projects, population growth rate, Energy issues, Water mismanagement, Economic changes, Expansions of projects and technology, Political issues, International water laws and Public awareness. To solve the problem of water scarcity in Iraq they should do the following: A. Reach agreements with Riparian Parties B. Develop Long-term Strategy that should take care of rehabilitating of hydrological projects, Improving the efficiency of diversion and supply, Using of Nonconventional Water Resources, Irrigation modernization using suitable techniques, Developing a Public awareness program and establishing an agenda for training.

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  • 45.
    Albert, Séréna
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Benthic-pelagic coupling in a changing world: Structural and functional responses of microbenthic communities to organic matter settling2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Marine soft sediments form the second largest habitat on the planet. Organisms residing in this environment represent a vast reservoir of biodiversity, and play key roles in ecosystem processes. Most benthic organisms depend on organic matter (OM) inputs from phytoplankton in the overlying water column as food supply, but human impacts such as eutrophication and climate change are profoundly altering natural ecosystem dynamics. The consequences of changes in benthic-pelagic coupling for the biodiversity and functioning of soft-sediment communities have yet to be resolved. 

    The aim of this thesis is to assess the role of OM settling on soft-sediments microeukaryotic (small organisms < 1 mm) and bacterial communities. The intents are two-fold, to investigate impacts on (1) community structure and diversity (chapters I, II and IV); and (2) ecosystem functioning, notably in relation to nitrogen (N) cycling (chapters I and III). 

    Our results show that settling OM quantity and quality both had a significant impact on microeukaryotic alpha-diversity. We observed a decrease in alpha-diversity following settling of diatom-derived spring bloom OM, possibly as a result of competitive exclusion, while cyanobacteria-derived summer bloom OM did not affect alpha-diversity (chapters I and IV). We also found that high biomass of diatoms and others fast sinking phytoplankton groups in the water column led to lower microeukaryotic alpha diversity after this material settled on the seafloor (chapter IV). Presumably, following this large sedimentation event, sediment oxygen (O2) demand was strongly stimulated, excluding O2-sensitive taxa. Overall, we propose that the assembly of microeukaryotic communities was primarily mediated by OM settling quantity (chapter IV), while differences in OM quality led to significant but more subtle changes, occurring at fine taxonomic level (chapter I). The response of bacterial communities to OM settling was less pronounced, and probably restricted to the uppermost sediment layer (chapters I and IV). We did, however, observe a significant effect of OM quality on bacterial communities assembly at the sediment-water interface, with taxa favored either by diatom- or by cyanobacteria-derived OM (chapter II). This study also showed that feedback mechanisms from nutrient recycling in the sediment could play a role in this response. Finally, our results indicated a substantial influence of OM quality on N cycling at the sediment-water interface. We found that settling of fresh OM (i.e. low C:N ratio) stimulated denitrification activity (chapters I and III), while simultaneously promoting more N recycling to the water column than settling of degraded OM (i.e. high C:N ratio) did (chapter III).  

    Altogether, our results indicate that current changes in OM settling dynamics in marine systems will likely impact microeukaryotic and, to some extent, bacterial biodiversity in soft sediments. Alterations in settling OM quality, in particular, may also affect crucial microbial processes involved in N cycling. This thesis highlights the importance of considering benthic-pelagic coupling mechanisms to better understand likely future changes in marine ecosystems.

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  • 46.
    Albertini, Cinzia
    et al.
    Univ Napoli Federico II, Dipartimento Ingn Civile Edile & Ambientale, I-80125 Naples, Italy.;Politecn Bari, Dipartimento Ingn Civile Ambientale Terr Edile &, I-70125 Bari, Italy..
    Mazzoleni, Maurizio
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Ctr Nat Hazards & Disaster Sci, S-75236 Uppsala, Sweden..
    Totaro, Vincenzo
    Politecn Bari, Dipartimento Ingn Civile Ambientale Terr Edile &, I-70125 Bari, Italy..
    Iacobellis, Vito
    Politecn Bari, Dipartimento Ingn Civile Ambientale Terr Edile &, I-70125 Bari, Italy..
    Di Baldassarre, Giuliano
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Ctr Nat Hazards & Disaster Sci, S-75236 Uppsala, Sweden..
    Socio-Hydrological Modelling: The Influence of Reservoir Management and Societal Responses on Flood Impacts2020In: Water, E-ISSN 2073-4441, Vol. 12, no 5, article id 1384Article in journal (Refereed)
    Abstract [en]

    Over the last few years, several socio-hydrological studies have investigated the risk dynamics generated by the complex interactions between floods and societies, with a focus on either changing reservoir operation rules or raising levees. In this study, we propose a new socio-hydrological model of human-flood interactions that represents both changes in the reservoir management strategies and updating of the levee system. Our model is applied to simulate three prototypes of floodplain management strategies to cope with flood risk: green systems, in which societies resettle outside the flood-prone area; technological systems, in which societies implement structural measures, such as levees; and green-to-techno systems, in which societies shift from green to technological approaches. Floodplain dynamics are explored simulating possible future scenarios in the city of Brisbane, Australia. Results show that flood risk is strongly influenced by changes in flood and drought memory of reservoir operators, while risk-awareness levels shape the urbanisation of floodplains. Furthermore, scenarios of more frequent and higher magnitude events prove to enhance social flood memory in green systems, while technological systems experience much higher losses. Interestingly, green-to-techno systems may also evolve toward green floodplain management systems in response to large losses and technical/economical unfeasibility of larger structural measures.

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  • 47.
    Alcolombri, Uria
    et al.
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland..
    Peaudecerf, Francois J.
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland..
    Fernandez, Vicente I.
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland..
    Behrendt, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental toxicology. Uppsala University, Science for Life Laboratory, SciLifeLab. Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland.
    Lee, Kang Soo
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland..
    Stocker, Roman
    Swiss Fed Inst Technol, Dept Civil Environm & Geomat Engn, Inst Environm Engn, Zurich, Switzerland..
    Sinking enhances the degradation of organic particles by marine bacteria2021In: Nature Geoscience, ISSN 1752-0894, E-ISSN 1752-0908, Vol. 14, no 10, p. 775-780Article in journal (Refereed)
    Abstract [en]

    The sinking of organic particles in the ocean and their degradation by marine microorganisms is one of the main drivers of the biological pump. Yet, the mechanisms determining the magnitude of the pump remain poorly understood, limiting our ability to predict this carbon flux in future ocean scenarios. Current ocean models assume that the biological pump is governed by the competition between sinking speed and degradation rate, with the two processes independent from one another. Contrary to this paradigm, we show that sinking itself is a primary determinant of the rate at which bacteria degrade particles. Heterotrophic bacterial degradation rates were obtained from a laboratory study on model surface-colonized particles at atmospheric pressure under a range of flow speeds to mimic different sinking velocities. We find that even modest sinking speeds of 8 m day−1 enhance degradation rates more than 10-fold compared with degradation rates of non-sinking particles. We discovered that the molecular mechanism underlying this sinking-enhanced degradation is the flow-induced removal from the particles of the oligomeric breakdown products, which otherwise compete for enzymatic activity. This mechanism applies across several substrates and bacterial strains, suggesting its potentially broad occurrence under natural marine conditions. Integrating our findings into a mathematical model of particulate carbon flux, we propose that the coupling of sinking and degradation may contribute, in conjunction with other processes, to determining the magnitude of the vertical carbon flux in the ocean.

  • 48.
    Aldama Campino, Aitor
    Stockholm University, Faculty of Science, Department of Meteorology .
    Atmospheric and oceanic circulation from a thermodynamic perspective2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The climate system is continuously transporting and exchanging heat, freshwater, carbon and other tracers in different spatio-temporal scales. Therefore, analysing the system from a thermodynamic or biogeochemical framework is highly convenient. In this thesis the interaction between the ocean and the atmospheric circulation is analysed using thermodynamical and biogeochemical coordinates. Due to the dimensionality of the climate system stream functions are used to reduce this complexity and facilitate the understanding of the different processes that take place. The first half of this thesis, focuses on the interaction between the atmospheric and the ocean circulation from a thermodynamic perspective. We introduce the hydrothermohaline stream function which combines the atmospheric circulation in humidity-potential temperature (hydrothermal) space and the ocean circulation in salinity-temperature coordinates (thermohaline). A scale factor of 7.1 is proposed to link humidity and salinity coordinates. Future scenarios are showing an increase of humidity in the atmosphere due to the increase of temperatures which results in a widening of the hydrothermal stream function along the humidity coordinate. In a similar way, the ocean circulation in the thermohaline space expands along the salinity coordinate. The link between salinity and humidity changes is strongest at net evaporation regions where the gain of water vapour in the atmosphere results in a salinification in the ocean. In addition, the ocean circulation in latitude-carbon space is investigated. By doing so, we are able to distinguish the roles of different water masses and circulation pathways for ocean carbon. We find that the surface waters in the subtropical gyres are the main drivers of the meridional carbon transport in the ocean. By separating the carbon in its different constituents we show that the carbon transported by the majority of the water masses is a result of the solubility pump. The contribution of the biological pump is predominant in the deep Pacific Ocean. The effects of the Mediterranean Overflow Waters on the North Atlantic are discussed in the final part of the thesis.

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  • 49. Alda-Vidal, C.
    et al.
    Kooy, M.
    Rusca, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Mapping operation and maintenance: an everyday urbanism analysis of inequalities within piped water supply in Lilongwe, Malawi2018In: Urban Geography, Vol. 39, no 1, p. 104-121Article in journal (Refereed)
    Abstract [en]

    In this article, we analyze the production of inequalities within the centralized water supply network of Lilongwe. We use a process-based analysis to understand how urban infrastructure is made to work and explain the disparity in levels of service by tracing the everyday practices of those who operate the infrastructure. This extends existing analyses of everyday practices in relation to urban water inequalities in African cities by focusing on formal operators, rather than water users, and looking within the networked system, rather than outside it. Our findings show that these practices work to exacerbate existing water stress in poor areas of the city. We conclude with a reflection on how understanding these practices as the product of the perceptions, rationalizations, and interpretations of utility staff who seek to manage the city’s (limited) water as best they can offers insight into what is required for a more progressive urban water politics.

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  • 50. Alda-Vidal, C.
    et al.
    Rusca, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Zwarteveen, M.
    Schwartz, K.
    Pouw, N.
    Occupational genders and gendered occupations: the case of water provisioning in Maputo, Mozambique2017In: Gender, Place and Culture: A Journal of Feminist Geography, ISSN 0966-369X, E-ISSN 1360-0524, Vol. 24, no 7, p. 974-990Article in journal (Refereed)
    Abstract [en]

    Taking issue with how associations between technical prowess or entrepreneurship and masculinity tend to be taken for granted or are seen as stemming from natural or intrinsic gender differences, over the last two decades feminist scholars have developed theoretical approaches to understand the gendering of professions and abilities as the performative outcome of particular cultures and histories. We build on these insights to explore how associations between masculinities, technology and entrepreneurship shape ideas and practices of small-scale water provision in Maputo. Our findings show how activities (i.e. technical craftsmanship, hard physical work) or abilities (i.e. risk-taking, innovativeness) regarded as masculine tend to be considered the defining features of the profession. This shapes how men and women make sense of and talk about their work, each of them tactically emphasizing and performing those aspects best fitting their gender. Our detailed documentation of men’s and women’s everyday involvements in water provisioning challenges the existence of sharp boundaries and distinctions between genders and professional responsibilities. It shows that water provisioning requires many other types of work and skills and male and female household members collaborate and share their work. The strong normative-cultural associations between gender and water provisioning lead to a distinct under-recognition of women’s importance as water providers. We conclude that strategies to effectively support small-scale water businesses while creating more space and power for women involved in the business require the explicit recognition and re-conceptualization of water provisioning as a household business.

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