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Greening of Svalbard
Get PDFSvalbard, located between 76°30′N and 80°50′N, is among the regions in the world with the most rapid temperature increase. We processed a cloud-free time-series of MODIS-NDVI for Svalbard. The dataset is interpolated to daily data during the 2000–2022 period with 232 m pixel resolution. The onset of growth, with a clear phenological definition, has been mapped each year. Then the integrated NDVI from the onset (O) of growth each year to the time of average (2000–2022) peak (P) of growth (OP NDVI) have been calculated. OP NDVI has previously shown high correlation with field-based tundra productivity. Daily mean temperature data from 11 meteorological stations are compared with the NDVI data. The OP NDVI values show very high and significant correlation with growing degree days computed from onset to time of peak of growth for all the meteorological stations used. On average for the entire Svalbard, the year 2016 first had the highest greening (OP NDVI values) recorded since the year 2000, then the greening in 2018 surpassed 2016, then 2020 surpassed 2018, and finally 2022 was the year with the overall highest greening by far for the whole 2000–2022 period. This shows a rapid recent greening of Svalbard very strongly linked to temperature increase, although there are regional differences: the eastern parts of Svalbard show the largest variability between years, most likely due to variability in the timing of sea-ice break-up in adjacent areas. Finally, we find that areas dominated by manured moss-tundra in the polar desert zone require new methodologies, as moss does not share the seasonal NDVI dynamics of tundra communities.publishedVersio
Numerical Simulations of Viscous Fingering in Fractured Porous Media
Get PDFThe effect of heterogeneity induced by highly permeable fracture networks on viscous miscible fingering in porous media is examined using high-resolution numerical simulations. We consider the planar injection of a less viscous fluid into a two-dimensional fractured porous medium that is saturated with a more viscous fluid. This problem contains two sets of fundamentally different preferential flow regimes; the first is caused by the viscous fingering, and the second is due to the permeability contrasts between the fractures and the rock matrix. We study the transition from the regime where the flow is dominated by the viscous instabilities, to the regime where the heterogeneity induced by the fractures define the flow paths. Our findings reveal that even minor permeability differences between the rock matrix and fractures significantly influence the behavior of viscous fingering. The interplay between the viscosity contrast and permeability contrast leads to the preferential channeling of the less viscous fluid through the fractures. Consequently, this channeling process stabilizes the displacement front within the rock matrix, ultimately suppressing the occurrence of viscous fingering, particularly for higher permeability contrasts. We explore three fracture geometries: two structured and one random configuration and identify a complex interaction between these geometries and the development of unstable flow. While we find that the most important factor determining the effect of the fracture network is the ratio of fluid volume flowing through the fractures and the rock matrix, the exact point for the cross-over regime is dependent on the geometry of the fracture network.publishedVersio
Assessing the potential for gas supersaturation downstream of hydropower plants in Norway, Austria and Germany
Get PDFHydroelectric power facilities can generate episodic total dissolved gas supersaturation (TDGS), which is harmful to aquatic life. We developed a decision tree-based risk assessment to identify the potential for TDGS at hydropower plants and conducted validation measurements at selected facilities. Applying the risk model to Norway's hydropower plants (n = 1696) identified 473 (28 %) high-risk plants characterized by secondary intakes and Francis or Kaplan turbines, which are prone to generating TDGS when air is entrained. More than half of them discharge directly to rivers (283, 17 % of total). Measurements at 11 high-risk plants showed that 8 of them exhibited biologically relevant TDGS (120 % to 229 %). In Austria and Germany, the analysis of hydropower plants was limited due to significant data constraints. Out of 153 hydropower plants in Austria, 80 % were categorized at moderate risk for TDGS. Two Austrian plants were monitored, revealing instances of TDGS in both (up to 125 %). In Germany, out of 403 hydropower plants, 265 (66 %) fell into the moderate risk, with none in the high-risk category. At a dam in the Rhine River, TDGS up to 118 % were observed. Given the uncertainty due to limited data access and the prevalence of run-of-river plants in Austria and Germany, there remains an unclarified risk of TDGS generation in these countries, especially at spillways of dams and below aerated turbines. The results indicate a previously overlooked potential for the generation of biologically harmful TDGS at hydropower installations. It is recommended to systematically screen for TDGS at hydropower installations through risk assessment, monitoring, and, where needed, the implementation of mitigation measures. This is increasingly critical considering the expanding global initiatives in hydropower and efforts to maintain the ecological status of freshwater ecosystems.publishedVersio
Advances in understanding of air-sea exchange and cycling of greenhouse gases in the upper ocean
Get PDFThe air–sea exchange and oceanic cycling of greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), carbon monoxide (CO), and nitrogen oxides (NOx = NO + NO2), are fundamental in controlling the evolution of the Earth’s atmospheric chemistry and climate. Significant advances have been made over the last 10 years in understanding, instrumentation and methods, as well as deciphering the production and consumption pathways of GHG in the upper ocean (including the surface and subsurface ocean down to approximately 1000 m). The global ocean under current conditions is now well established as a major sink for CO2, a major source for N2O and a minor source for both CH4 and CO. The importance of the ocean as a sink or source of NOx is largely unknown so far. There are still considerable uncertainties about the processes and their major drivers controlling the distributions of N2O, CH4, CO, and NOx in the upper ocean. Without having a fundamental understanding of oceanic GHG production and consumption pathways, our knowledge about the effects of ongoing major oceanic changes—warming, acidification, deoxygenation, and eutrophication—on the oceanic cycling and air–sea exchange of GHG remains rudimentary at best. We suggest that only through a comprehensive, coordinated, and interdisciplinary approach that includes data collection by global observation networks as well as joint process studies can the necessary data be generated to (1) identify the relevant microbial and phytoplankton communities, (2) quantify the rates of ocean GHG production and consumption pathways, (3) comprehend their major drivers, and (4) decipher economic and cultural implications of mitigation solutions.publishedVersio
Factors influencing microplastic abundances in the sediments of a seagrass-dominated tropical atoll
Get PDFSeagrass meadows are one of the world's most diverse ecosystems offering habitats for an extensive array of species, as well as serving as protectors of coral reefs and vital carbon sinks. Furthermore, they modify hydrodynamics by diminishing water flow velocities and enhancing sediment deposition, indicating the potential for microplastic accumulation in their sediments. The build-up of microplastics could potentially have ecological impacts threatening to ecosystems, however little is known about microplastic abundance and controlling factors in seagrass sediments. Here we investigated microplastic characteristics and abundances within sediments underlying four seagrass meadow sites on the Turneffe Atoll, Belize. Sediment cores were collected and sub-sampled to include a range of replicate surface sediments (0–4 cm) and depth cores (sediment depths 0–2, 2–5, 5–10, 10–20 and 20–30 cm). These were analysed using 25 μm resolution μFTIR, with spectral maps processed using siMPle software. Microplastics were prevalent across the sites with an abundance range (limit of detection (LOD) blank-corrected) of < LOD to 17137 microplastics kg−1 dw found on the east side of the atoll. However, their abundances varied greatly between the replicate samples. Polyethylene and polypropylene were the most commonly detected polymers overall, although the dominant polymer type varied between sites. There were no differences in the abundance of microplastics between sites, nor could abundance distributions be explained by seagrass cover. However, abundances of microplastics were highest in sediments with lower proportions of fine grained particles (clay, <4 μm) suggesting that hydrodynamics override seagrass effects. Additionally, no patterns were seen between microplastic abundance and depth of sediment. This suggests that microplastic abundance and distribution in seagrass meadows may vary significantly depending on the specific geographical locations within those meadows, and that more complex hydrodynamic factors influence spatial variability at a localised scale.publishedVersio
Protective factors associated with resilience among unaccompanied refugee minors after settling in Norway: a matched cross-sectional study
Get PDFThis study aimed to examine protective factors associated with resilience among unaccompanied refugee minors in comparison to their Norwegian peers and to examine associations between resilience factors and characteristics related to positive outcomes among unaccompanied minors. Data stem from the Pathways to Independence study conducted in Bergen municipality, Norway in 2018–2019 where 81 unaccompanied minors aged 15–20 participated (83.3% male; 80% response rate). An age- and sex-matched control group of 324 adolescents was retrieved from the youth@hordaland study conducted in Norway in 2012. Resilience factors were assessed by the Resilience Scale for Adolescents. Unaccompanied minors reported lower scores on Goal Orientation (d = 0.4), Social Competence (d = 0.4), and Social Support (d = 0.7) compared to Norwegian adolescents. Being male was associated with lower scores on Goal Orientation (standardized mean difference [SMD] = − 0.9) and Social Support (SMD = − 0.9) among unaccompanied minors, while being in frequent contact with family in the home country was associated with higher scores on all resilience factors (SMD range = 0.6–1.1). The number of leisure activities was associated with Social Competence (SMD = 0.22). There were no significant associations between the resilience factors and amount of support in the living arrangements or contact with the child welfare services. Unaccompanied minors reported fewer resilience factors compared to Norwegian adolescents, indicating that they may have different needs compared to other adolescents. Our study also suggests that frequent contact with family in the home country may be important to bolster positive development for unaccompanied minors after settlement.publishedVersio
«Oss og vårt», en samskapende prosess for bedre arbeidsmiljø - en evaluering
Get PDFDet overordnede målet med dette prosjektet har vært å evaluere arbeidsmiljøverktøyet «Oss og vårt», samt å belyse i hvilken grad verktøyet kan bidra til å nå IA-avtalens mål om bedre arbeidsmiljø, og redusert fravær og frafall på kort og lang sikt. Det ble gjennomført 3 fokusguppeintervju med til sammen 9 IA-, BHT-, og HR-rådgivere, samt historieverksteder og intervjuer ved 7 sykehjem. Hovedfunnet viser at «Oss og vårt» på kort sikt kan bidra til å løse lokale utfordringer knyttet til organisering, planlegging og gjennomføring av arbeidet som kan bidra til å redusere anerkjente risikofaktorer. Videre fremkommer det av resultatene at metodikken ressurskrevende, og hverdagen på sykehjemmene hemmer kontinuiteten i prosessen. Dersom tiltaket skal kunne bidra til en forbedring av arbeidsmiljø og reduksjon av fravær og frafall på lang sikt fordrer det at bruken av verktøyet forankres på alle nivå i organisasjonen.«Oss og vårt», en samskapende prosess for bedre arbeidsmiljø - en evalueringpublishedVersio
Developmental dyslexia in children with perinatal exposure to hypoxia: A systematic review
Get PDFBackground Research on a health-related event at the stage of labour and the occurrence of adverse outcomes at the school age has provided inconclusive results. Thus far, no systematic reviews have been conducted. Thus, the objective of this study is to investigate the association between hypoxia during pregnancy or delivery and the subsequent occurrence of a developmental dyslexia in school-age children. Methods We used a standard search strategy of electronic databases (PubMed, PsycINFO, Web of Science, EMBASE, and Cochrane Library) and handsearching. We included observational studies (cohort studies, case-control studies) that consider as an exposure the presence of hypoxia during pregnancy or delivery, and as an outcome, developmental dyslexia in school-age children. Two reviewers independently conducted the search and determined eligibility, which was not restricted by language or year of publication. Results The search took place until 1 April 2023. Of the 1,336 abstracts screened, 6 were assessed for eligibility. Of the six eligible studies, no studies met the pre-specified eligibly criteria. Conclusions We were unable to assess the association between hypoxia and developmental dyslexia, as no eligible studies were found. Thus, the association between hypoxia during pregnancy or delivery and dyslexia in school-age children remains unknown.publishedVersio
Transnational experience exchange between countries towards speeding up EU renewable transition: example of Norway-Croatia
Get PDFThe RePowerEU plan aims to increase wind energy capacity to 480 GW by 2030, with 300 GW coming from offshore wind farms, to achieve climate neutrality by 2050. Due to Croatia's substantial dependence on nautical and coastal tourism, along with significant concerns regarding negative environmental impacts, the installation of offshore wind farms has not been previously considered. However, due to increased demand for renewables, the offshore energy potential resurfaced. The recent Action Plan for the Uptake of Offshore Renewable Energy Sources in Croatia (May 2023) estimated offshore wind potential at 25 GW and identified more than 29 000 km2 of area available for offshore renewables. Norway, with its extensive experience in offshore engineering and pioneering developments in offshore wind, is a suitable partner in joint innovation and a resource for tried and tested best practices. In this collaborative research, a review of relevant documents, research articles, and interviews with industry experts from both from Croatia and Norway was conducted to obtain a broader perspective of the implications of offshore development in Croatia. As an outcome of this preliminary research, the paper outlines the required evaluations in the Croatian context, in terms of the social, environmental, legislative, and technical aspects that are to be considered for large-scale integration of wind energy into the Croatian grid. It also identifies the necessary grid improvements to achieve a reliable and sustainable grid of the future.publishedVersio
Medically assisted integrated rehabilitation program for people with opioid dependence: a quasi-experimental evaluation using multi-criteria decision analysis
Get PDFBackground Opioid use disorders constitute a vast disease burden, need for comprehensive treatment, and substantial costs to individuals, families, and society. The multifaceted needs of people with opioid dependence call for integrated care. The study aims to assess the added value of an integrated medically assisted rehabilitation (MAR) program providing opioid agonist therapy for patients with opioid dependence as compared to the standard of care (SoC) in Norway. Methods The intervention includes a comprehensive tertiary care integrated MAR program in Bergen. SoC is a much less intense primary care program in Oslo. 682 and 609 patients from Bergen, and 864 and 771 patients from Oslo were included in 2017 and 2019, respectively. A multi-criteria decision analysis (MCDA) framework was used where the relative preferences of the importance of the outcomes were obtained from a discrete choice experiment among five different stakeholder-groups. Seven outcomes related to health, well-being, experience of the care process, and cost were measured. The performance scores were measured in a study with a quasi-experimental design. Scores were analyzed using linear mixed methods. Performance scores for the outcomes were standardized and multiplied by their relative preferences to obtain the overall value scores in the MCDA. Results We found similar value scores for both care delivery models regarding physical functioning, psychological well-being, social relationships & participation, enjoyment of life, and total costs. The Bergen-model scored higher on continuity of care (0.733 versus 0.680), while the SoC-model scored higher on person-centeredness (0.772 versus 0.635). Overall value scores were marginally in favor of the MAR-Bergen (0.708 versus 0.705 for patients). Conclusion Acknowledging the significance of different life aspects emphasizes the need for integrated care at a specific level for people with opioid dependence. We conclude that the two highly effective treatment approaches produce promising outcomes in a challenging population and are quite similar. However, further research with more robust longitudinal data is needed.publishedVersio