1,720,980 research outputs found
Modelling the effects of climate change and sea level rise on the evolution of incised coastal gullies
No full textUnder projections of future (next ~100 years) anthropogenic climate change, it is predicted that marked changes in environmental driving conditions, with relation to baseline (1961 - 1990) climates, will be experienced. Such changes have the potential to induce substantial geomorphological and ecological change. Numerical models of landscape evolution provide powerful tools to assess the impacts that environmental changes may have on landscape morphology. Accordingly, this research seeks to utilise landscape evolution models (LEMs) to understand how projected changes in climate will affect the geomorphic response of a series of incised coastal gullies found on the Isle of Wight, UK. Incised coastal gullies are known to be dynamic and sensitive landscape features which intersect the terrestrial - marine boundary; as such their evolution is influenced by changes in both terrestrial (i.e. precipitation) and maritime (i.e. sea level and wave height) climates. In order to ensure the processes driving incised coastal gully evolution are represented within the LEM, an existing LEM was modified to include processes of soft cliff erosion. This represents the first such inclusion of coastal processes within a LEM framework. The modified LEM was forced with ensemble projections of precipitation, sea level and wave height downscaled from HadCM3 and CGCM2 Global Climate Model (GCM) outputs for two emissions scenarios (A2 and B2). Comparison against a baseline scenario based on the 1961-1990 climatology allows for climate induced changes in system response to be quantified. To constrain the uncertainties associated with the application of landscape models and downscaled GCM data, a Monte Carlo analysis framework is employed, resulting in ~22000 model runs. This method also permits the development of probabilistic results describing geomorphological change in gully systems. Results suggest that the likelihood of extreme loss in gully extent will increase by up to 61%. Furthermore, it is projected that extreme rates of coastal erosion will increase by 22% by 2100 (under HadCM3 runs forced with the A2 emissions scenario). However, under certain scenarios the possibility of extension of the gully systems exists, with likely (>66% probability) increases in gully length of 13.7 m projected under CGCM2 runs forced with the A2 emissions scenario. The novel application of a Monte Carlo methodology with a LEM framework permits the identification of key climatic parameters responsible for causing extreme changes within these gully systems, allowing the relative importance of each climate parameter in driving incised coastal gully evolution to be assessed. Furthermore, the successful application of this technique suggests it may be applicableto other studies applying LEMs to scenarios of future climate change
Modelling the response of soft cliffs to climate change: a statistical, process-response model using accumulated excess energy
No full textLandscapes on the edge: examining the role of climatic interactions in shaping coastal watersheds using a coastal-terrestrial landscape evolution model
No full textIncised coastal gullies (ICGs) are dynamic features found at the terrestrial-coastal interface. Their geomorphic evolution is driven by the interactions between processes of fluvial knickpoint migration and coastal cliff erosion. Under scenarios of future climate change the frequency and magnitude of the climatological drivers of both terrestrial (fluvial and hillslope) and coastal (cliff erosion) processes are likely to change, with an adjunct impact on these types of coastal features. Here we explore the response of an incised coastal gully to changes in both terrestrial and coastal climate in order to elucidate the key process interactions which drive ICG evolution.We modify an extant landscape evolution model, CHILD, to incorporate processes of soft-cliff erosion. This modified version, termed the Coastal-Terrestrial-CHILD (CT-CHILD) model, is then employed to explore the interactions between changing terrestrial and coastal driving forces on the future evolution of an ICG found on the south west Isle of Wight, UK. It was found that the magnitude and frequency of storm events will play a key role in determining the future trajectory of ICGs, highlighting a need to understand the role of event sequencing in future projections of landscape evolution. Furthermore, synergistic (positive) and antagonistic (negative) interactions were identified between coastal and terrestrial parameters, such as wave height intensity and precipitation duration, which act to modulate the impact of changes in any one parameter. Of note was the role played by wave height intensity in driving coastal erosion, which was found to play a more important role than sea-level rise in determining rates of coastal erosion. This highlights the need for a greater focus on wave height in studies of soft-cliff erosion
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
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