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Dataset supporting the article: "Future Decreases in Thermospheric Neutral Density in Low Earth Orbit due to Carbon Dioxide Emissions"
No full textThis dataset is supporting the article
"Future Decreases in Thermospheric Neutral Density in Low Earth Orbit due to Carbon Dioxide Emissions".
Published in JGR Atmospheres, Volume126, Issue8, 27 April 2021,
e2021JD034589
https://doi.org/10.1029/2021JD034589
The data portrays Neutral density scaling tables for empirical atmospheric models to account for thermospheric contraction due to carbon dioxide emissions.
Scaling factors that can be applied to the neutral densities obtained from empirical atmospheric models, particularly NRLMSISE-00. These are designed to account for the reductions in density within the upper atmosphere caused by carbon dioxide emissions. They were created using WACCM-X (see https://doi.org/10.1029/2021JD034589 for further details on the low solar activity data). Each scaling factor is relative to the year 2000, and is dependent upon altitude (range 100-500 km), solar activity through F10.7 (70-200 sfu) and ground-level carbon dioxide concentration (368.9 to 890.0 ppm, covering years 2000-2100 in the RCP8.5 scenario). RCP refers to the Representative Concentration Pathways of the IPCC's Fifth Assessment Report. ScalingArray.txt is dependent upon carbon dioxide concentration, while each .txt file with an RCP appended is dependent upon the year (2000-2100) instead, following the carbon dioxide concentrations of the named RCP. Each file contains information on the format of the table used.</span
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Future Decreases in Thermospheric Neutral Density in Low Earth Orbit due to Carbon Dioxide Emissions
Full text linkIncreasing carbon dioxide causes cooling in the upper atmosphere and a secular decrease in atmospheric density over time. With the use of the Whole Atmospheric Community Climate Model with thermosphere and ionosphere extension (WACCM‐X), neutral thermospheric densities up to 500 km have been modelled under increasing carbon dioxide concentrations. Only carbon dioxide and carbon monoxide concentrations are changed between simulations, and solar activity is held low at F10.7 = 70 throughout. Neutral density decreases through to the year 2100 have been modelled using four carbon dioxide emission scenarios produced by the Intergovernmental Panel on Climate Change (IPCC). The years 1975 and 2005 have also been simulated, which indicated a historic trend of ‐5.8% change in neutral density per decade. Decreases in the neutral density relative to the year 2000 have been given for increasing ground‐level carbon dioxide concentrations. WACCM‐X shows there has already been a 17% decrease in neutral densities at 400 km relative to the density in the year 2000. This becomes a 30% reduction at the 50:50 probability threshold of limiting warming to 1.5°C, as set out in the Paris Agreement. A simple orbital propagator has been used to show the impact the decrease in density has on the orbital lifetime of objects travelling through the thermosphere. If the 1.5°C target is met, objects in LEO will have orbital lifetimes around 30% longer than comparable objects from the year 2000
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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