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Ecotoxicological assessment of sediments dredged from Numana harbor 2023
Ecotoxicological assessment of sediments dredged from Numana harbor 2023publishedVersio
An agenda for the future of Arctic snow research: the view from Svalbard
The Arctic region is warming at over twice the mean rate of the Northern Hemisphere and nearly four times faster than the globe since 1979. The local rate of warming is even higher in the European archipelago of Svalbard. This warming is transforming the terrestrial snow cover, which modulates surface energy exchanges with the atmosphere, accounts for most of the runoff in Arctic catchments and is also a transient reservoir of atmospherically deposited compounds, including pollutants. Improved observations, understanding and modelling of changes in Arctic snow cover are needed to anticipate the effects these changes will have on the Arctic climate, atmosphere, terrestrial ecosystems and socioeconomic factors. Svalbard has been an international hub of polar research for many decades and benefits from a well-developed science infrastructure. Here, we present an agenda for the future of snow research in Svalbard, jointly developed by a multidisciplinary community of experts. We review recent trends in snow research, identify key knowledge gaps, prioritize future research efforts and recommend supportive actions to advance our knowledge of present and future snow conditions pertaining to glacier mass balance, permafrost, surface hydrology, terrestrial ecology, the cycling and fate of atmospheric contaminants, and remote sensing of snow cover. This perspective piece addresses issues relevant to the circumpolar North and could be used as a template for other national or international Arctic research plans.publishedVersio
Three major mesoplanktonic communities resolved by in situ imaging in the upper 500 m of the global ocean
Aim The distribution of mesoplankton communities has been poorly studied at global scale, especially from in situ instruments. This study aims to (1) describe the global distribution of mesoplankton communities in relation to their environment and (2) assess the ability of various environmental-based ocean regionalizations to explain the distribution of these communities. Location Global ocean, 0–500 m depth. Time Period 2008–2019. Major Taxa Studied Twenty-eight groups of large mesoplanktonic and macroplanktonic organisms, covering Metazoa, Rhizaria and Cyanobacteria. Methods From a global data set of 2500 vertical profiles making use of the Underwater Vision Profiler 5 (UVP5), an in situ imaging instrument, we studied the global distribution of large (>600 μm) mesoplanktonic organisms. Among the 6.8 million imaged objects, 330,000 were large zooplanktonic organisms and phytoplankton colonies, the rest consisting of marine snow particles. Multivariate ordination (PCA) and clustering were used to describe patterns in community composition, while comparison with existing regionalizations was performed with regression methods (RDA). Results Within the observed size range, epipelagic plankton communities were Trichodesmium-enriched in the intertropical Atlantic, Copepoda-enriched at high latitudes and in upwelling areas, and Rhizaria-enriched in oligotrophic areas. In the mesopelagic layer, Copepoda-enriched communities were also found at high latitudes and in the Atlantic Ocean, while Rhizaria-enriched communities prevailed in the Peruvian upwelling system and a few mixed communities were found elsewhere. The comparison between the distribution of these communities and a set of existing regionalizations of the ocean suggested that the structure of plankton communities described above is mostly driven by basin-level environmental conditions. Main Conclusions In both layers, three types of plankton communities emerged and seemed to be mostly driven by regional environmental conditions. This work sheds light on the role not only of metazoans, but also of unexpected large protists and cyanobacteria in structuring large mesoplankton communities.Three major mesoplanktonic communities resolved by in situ imaging in the upper 500 m of the global oceanpublishedVersio
Warmer and wetter: Outlining climate services for snow-dependent tourism in Norway – The case of Lofoten
Human-induced climate change potentially impacts nature-based activities in Lofoten and may limit the attractiveness of the destination for tourists seeking recreation and adventure in the mountains. As a climate service, we calculated climate indicators relevant to the tourism sector based on the representative concentration pathways RCP4.5 and RCP8.5 until 2060. We used high-resolution gridded climate data and projections to calculate indicators such as changes in the frequency and intensity of consecutive wet days, changes in precipitation type (snow, sleet, rain), changes in the number of skiing days on ungroomed, natural snow, and changes of the monthly 0 °C-isoline. We found a minor, but non-robust increase in the number of consecutive wet days with a precipitation intensity > 8 mm/day, and a clear change in the precipitation regime depending on altitude that leads to more precipitation falling as rain instead of snow. Also, a strong decrease in the number of skiing days is projected by the climate models as the monthly near-surface 0 °C-isoline increases. These are important findings for long-term planning and investments in the tourism sector in Lofoten, especially as tourism growth is considered an important tool for regional economic development. The analytical methods used in this study are transferable to analyses on a regional to national scale. National maps and data material for 11 regions were recently published onWarmer and wetter: Outlining climate services for snow-dependent tourism in Norway – The case of LofotenpublishedVersio
Sampling-Based Methods for Uncertainty Propagation in Flood Modeling Under Multiple Uncertain Inputs: Finding Out the Most Efficient Choice
In probabilistic flood modeling, uncertainty manifests in frequency of occurrence, or histograms, for quantities of interest, including the Flood Extent and hazard rating (HR). Such modeling at the field-scale requires the identification of a more efficient alternative to the Standard Monte Carlo (SMC) method that can reproduce comparable output probability distributions with a relatively reduced sample size, including detailed histograms of quantities of interest. Latin hypercube sampling (LHS) is the most evaluated alternative for fluvial floods but yields no considerable sample size reduction. Potentially better alternatives include adaptive stratified sampling (ASS), Quasi Monte Carlo (QMC) and Haar-wavelet expansion (HWE), which are yet unevaluated for probabilistic flood modeling. To fulfill this gap, LHS, ASS, QMC, and HWE are compared to quantify sample size reduction to reproduce output detailed histograms—for Flood Extent, and average and maximum HR—while keeping the difference below 10% to the reference SMC prediction. The comparison is done for two test cases with two (i.e., inflow discharge and Manning's coefficient) and three (i.e., further including the ground elevation) input random variables, and a real case with five input random variables. With two input random variables, all four alternatives yield sample size reductions, with QMC and HWE considerably outperforming the others; with three and more input random variables, HWE becomes inflexible and LHS underperforms. Still, QMC is a better choice than ASS to boost sample size reduction for the real case and shall be preferred in probabilistic flood modeling. Accompanying research codes are openly available online.Sampling-Based Methods for Uncertainty Propagation in Flood Modeling Under Multiple Uncertain Inputs: Finding Out the Most Efficient ChoicepublishedVersio
Deep Convection as the Key to the Transition From Eocene to Modern Antarctic Circumpolar Current
From the Eocene (∼50 million years ago) to today, Southern Ocean circulation has evolved from the existence of two ocean gyres to the dominance of the Antarctic Circumpolar Current (ACC). It has generally been thought that the opening of Southern Ocean gateways in the late Eocene, in addition to the alignment of westerly winds with these gateways or the presence of the Antarctic ice sheet, was a sufficient requirement for the transition to an ACC of similar strength to its modern equivalent. Nevertheless, models representing these changes produce a much weaker ACC. Here we show, using an eddying ocean model, that the missing ingredient in the transition to a modern ACC is deep convection around the Antarctic continent. This deep convection is caused by cold temperatures and high salinities due to sea-ice production around the Antarctic continent, leading to both the formation of Antarctic Bottom Water and a modern-strength ACC.publishedVersio
Insights into the vulnerability of Antarctic glaciers from the ISMIP6 ice sheet model ensemble and associated uncertainty
The Antarctic Ice Sheet represents the largest source of uncertainty in future sea level rise projections, with a contribution to sea level by 2100 ranging from −5 to 43 cm of sea level equivalent under high carbon emission scenarios estimated by the recent Ice Sheet Model Intercomparison for CMIP6 (ISMIP6). ISMIP6 highlighted the different behaviors of the East and West Antarctic ice sheets, as well as the possible role of increased surface mass balance in offsetting the dynamic ice loss in response to changing oceanic conditions in ice shelf cavities. However, the detailed contribution of individual glaciers, as well as the partitioning of uncertainty associated with this ensemble, have not yet been investigated. Here, we analyze the ISMIP6 results for high carbon emission scenarios, focusing on key glaciers around the Antarctic Ice Sheet, and we quantify their projected dynamic mass loss, defined here as mass loss through increased ice discharge into the ocean in response to changing oceanic conditions. We highlight glaciers contributing the most to sea level rise, as well as their vulnerability to changes in oceanic conditions. We then investigate the different sources of uncertainty and their relative role in projections, for the entire continent and for key individual glaciers. We show that, in addition to Thwaites and Pine Island glaciers in West Antarctica, Totten and Moscow University glaciers in East Antarctica present comparable future dynamic mass loss and high sensitivity to ice shelf basal melt. The overall uncertainty in additional dynamic mass loss in response to changing oceanic conditions, compared to a scenario with constant oceanic conditions, is dominated by the choice of ice sheet model, accounting for 52 % of the total uncertainty of the Antarctic dynamic mass loss in 2100. Its relative role for the most dynamic glaciers varies between 14 % for MacAyeal and Whillans ice streams and 56 % for Pine Island Glacier at the end of the century. The uncertainty associated with the choice of climate model increases over time and reaches 13 % of the uncertainty by 2100 for the Antarctic Ice Sheet but varies between 4 % for Thwaites Glacier and 53 % for Whillans Ice Stream. The uncertainty associated with the ice–climate interaction, which captures different treatments of oceanic forcings such as the choice of melt parameterization, its calibration, and simulated ice shelf geometries, accounts for 22 % of the uncertainty at the ice sheet scale but reaches 36 % and 39 % for Institute Ice Stream and Thwaites Glacier, respectively, by 2100. Overall, this study helps inform future research by highlighting the sectors of the ice sheet most vulnerable to oceanic warming over the 21st century and by quantifying the main sources of uncertainty.publishedVersio
Participatory research approaches to studying social capital in youth mentoring: Not the panacea we hoped for
Participatory approaches have gained broad interest among researchers as a vehicle for allowing participants’ experiences and voices to inform research, beyond simply being a source of data. However, participants in mentoring programs, particularly young people, often are not included in research partnerships in a meaningful way. Additionally, practitioners often struggle to translate research findings into program improvements. This paper examines the experiences of a research team collaborating with two user groups: mentoring practitioners, and youth with migrant and refugee backgrounds participating in mentoring programs. With ambitions for meaningful user involvement, our aim was to develop and test a digital intervention for supporting social capital in mentoring. The paper draws primarily upon participant observation and qualitative data from a focus group and panel discussions. While youth voices did inform and shape the research, we also experienced challenges related to youth understanding and engagement. The adult practitioners participated actively but encountered tensions due to their dual roles as co-researchers and mentoring professionals, and resource constraints. Ultimately, a close collaboration enabled the co-creation of adaptations to our research approaches, allowing meaningful participation for some of the youth, and facilitating program changes. This paper offers lessons for researchers wishing to conduct participatory research in the context of youth mentoring, as well as specific suggestions for those studying social capital. It contributes to the discussion on participatory approaches with multicultural youth, presenting critical reflections on our experiences within this mentoring context.publishedVersio
Does shared service delivery affect cost? A study of the cost-capacity relation in Norwegian local child protection services
Intermunicipal cooperation is often seen as a means to increase capacity and reap economic benefits of scale. Prior research, however, shows that the effects of shared service delivery diverge, leaving scholars and practitioners to question whether, under what conditions and at what expense effects of cooperation manifest. Using a panel dataset on child protection services, we analyze how cooperation affects the cost-capacity relation. The results show that cooperation increases cost. This increase is only partly explained by investments in service capacity, indicating that there are significant transaction costs linked to cooperation as a mode of production.publishedVersio
Field report for snorkeling surveys and removal of escaped farmed salmon in 13 rivers in Iceland 2023
In August 2023, the aquaculture company Arctic Fish (Arctic Sea Farm) reported two small holes in one of its net-pens in Patreksfjörður in the Westfjords, Iceland. The Icelandic Food and Veterinary Authority estimated that about 3500 farmed salmon escaped from the net-pen. On assignment from the Directorate of fisheries in Iceland, NORCE LFI surveyed 13 rivers on the north and west coast of Iceland by snorkeling in September-October. The objective was to screen key segments of the rivers for farmed fish and remove as many as possible using spearguns, to limit negative impacts of farmed salmon spawning with wild salmon. Likely hotspots for occurrence of farmed salmon were chosen based on experience from Norway and guidance from local river owners and fishing guides. Escaped farmed salmon was found in 9 of the 13 rivers. A total of 79 farmed fish were observed, whereof 59 were caught, while 7 more were shot and wounded but managed to escape. The highest number of farmed salmon were found in Hrútafjarðará (34 observed, 32 caught). The farmed salmon were in general found in the upper reaches of the rivers, often in pools below rapids and waterfalls, or in association with holding pools/spawning areas together with aggregations of wild salmon. In some instances, farmed salmon were located more than 20 km upriver from the sea, demonstrating the possibility and motivation of the farmed salmon to migrate extensive distances up the rivers. All the surveyed rivers were considered suitable for performing snorkeling surveys, but varying visibility affected the possibilities to effectively observe and hunt farmed fish in the different rivers. The results suggest that snorkeling surveys and speargun fishing may be a useful approach to monitor and reduce the impacts of escaped farmed salmon in Icelandic rivers in case of future incidences.publishedVersio