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    SESS Report 2021 The State of Environmental Science in Svalbard - an annual report

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    Executive Summary The State of Environmental Science in Svalbard (SESS) report 2021 together with its predecessors contributes to the documentation of the state of the Arctic environment in and around Svalbard, and highlights research conducted within the Svalbard Integrated Arctic Earth Observing System (SIOS). Climate change is a global problem, but many of its impacts are being felt most strongly in the Arctic. Given its remote but accessible location, Svalbard constitutes an ideal place to study the Arctic environment in general, including, more specifically, the causes and consequences of climate change. The Arctic Climate Change Update (2021) emphasised the severity of global climate change for ecosystems across the Arctic. They are undergoing radical changes regarding their structure and functioning, affecting flora, fauna and livelihoods of Arctic communities. Oceanic ecosystems and food webs are directly and indirectly altered by the warming and freshening of the Arctic Ocean. A prolonged open water period and the expansion of open water areas caused by declining sea ice affect under-ice productivity and diversity. These changes have cascading effects through ecosystems and impact the distribution, abundance and seasonality of a variety of marine species. Svalbard is located at one of the key oceanic gateways to the Arctic. This land–ice–ocean transition zone is a system particularly vulnerable to environmental changes. Svalbard’s environment is influenced by maritime processes; thus extensive observation of the ocean system is nowadays necessary. The chapter on the iMOP project reports seawater temperature and salinity variability over the last decades and indicates changes of Svalbard fjord seawater properties. The chapter highlights the role of a collaborative and supportive network of observatory operators and encourages joint planning and maintenance of future marine observatories. Arctic vegetation plays a key role in land–atmosphere interactions. Alterations can lead to ecosystem–climate feedbacks and exacerbate climate change. Extreme precipitation events are already becoming more frequent. Together with an increasing rain-to-snow ratio they impact the structure and functioning of terrestrial ecosystems. Dynamics in Arctic tundra ecosystems are expected to undergo fundamental changes with increasing temperatures as predicted by climate models. To detect, document, understand and predict those changes, COAT Svalbard provides a long-term and real-time operational observation system through ecosystem-based terrestrial monitoring. The observation system consists of six modules comprising food web pathways as well as one climate-monitoring module and focuses on two contrasting regions in Svalbard to allow for intercomparison. To date, the project has done an initial assessment of tundra ecosystems in Norway and will now begin with the long-term ecosystembased monitoring. For remote regions such as the Svalbard archipelago, terrestrial photography is a crucial addition to satellite imagery, because land-based cameras offer high temporal resolution and insensitivity towards varying weather conditions. PASSES provides an overview of cameras operating in Svalbard managed by research institutions and private companies. The survey revealed difficulties and knowledge gaps preventing the full potential of the terrestrial photography network in Svalbard from being used. Therefore, PASSES recommends the creation of a Svalbard camera system network. The effects of climate change contributed to a specific anomaly of the springtime Arctic atmosphere, namely a pronounced depletion of stratospheric ozone during March and April 2020, which can be called an Arctic ozone hole. In Svalbard, the amount of ozone loss was recorded by ground-based dedicated spectroscopic instruments measuring the total ozone column as well as the UV irradiance (EXAODEP-2020, an update of UV Ozone). The latter is important for effects on the biota. Corresponding erythemal daily doses for spring 2020 show a doubling compared to previous years with less or no ozone depletion. While the correspondence between ozone loss and increase in UV doses follows a well-known relationship, the possible later consequences of the observed springtime increase of UV doses on Svalbard’s environment need to be further studied. A particular method to observe the Svalbard environment, which has seen a very strong increase in usage during recent years, is the application of unmanned airborne or marine vehicles. The update on recent publications using these devices (UAV Svalbard) reveals that especially conventional remotely operated aerial vehicles (drones) with camera equipment are now widely used. It is recommended to SIOS to foster interdisciplinary communication among the multitude of drone users to establish exchange of information and data. New EU regulations for drone operations are being put in place from 2022 onwards also in Svalbard. Climate services are receiving more and more attention from Arctic countries, because they translate data into relevant and timely information, thereby supporting governments, societies and industries in planning and decision-making processes. SIOS contributes to climate services by providing research infrastructure with an overarching goal to develop and maintain a regional observational system for long-term measurements in and around Svalbard. The SIOS Core Data (SCD) consists of a list of essential Earth System Science variables relevant to determine environmental change in the Arctic. SCD is developed to improve the relevance and availability of scientific information addressing ESS topics for decision-making. SIOS Core Data providers have committed to maintain the observations for at least five years, to make the data publicly available, and to follow advanced principles of scientific data management and stewardship. Arctic climate change is posing risks to the safety, health and well-being of Arctic communities and ecosystems. Still, there remain gaps in our understanding of physical processes and societal implications. The authors of the SESS chapters have highlighted some unanswered questions and suggested concrete actions that should be taken to address them. The editors would like to thank the authors for their valuable contributions to the SESS Report 2021. These chapters illustrate how SIOS projects contribute to ensure the future vitality and resilience of Arctic peoples, communities and ecosystems

    LIDAR measurements at AWIPEV (1999-12)

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    Height of tropopause: doi:10.1594/PANGAEA.771549, extinction to backscatter ratio to 353.07 nm: 30, extinction to backscatter ratio to 532.07 nm: 40 Detection channels at 1064 nm, 607 nm, 532 nm (aligned- and cross-polarized), 385 nm, 353 nm using photon counting mode. A mechanical chopper prevents photodetector saturation at low altitudes. Each data set is based on a signal average of 10 minutes. The backscatter ratio is calculated using Klett's algorithm. Profiles of the molecular backscatter coefficient are calculated from a density profile obtained from daily meteorological soundings. Lidar data profiles are normalized to a backscatter ratio value of 1.0 between 25 and 30 km. Volume depolarisation is calculated as the ratio of the perpendicular and parallel lidar signals. Depolarization is normalized to the molecular value of 0.014 between 25 and 30 km

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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