1,721,025 research outputs found
Impact of climate variability on summer fires in a Mediterranean environment (northeastern Iberian Peninsula)
Get PDFWe analyse the impact of climate interannual variability on summer
forest fires in Catalonia (northeastern Iberian Peninsula). The study
period covers 25 years, from 1983 to 2007. During this period more than
16000 fire events were recorded and the total burned area was more than
240 kha, i.e. around 7.5% of whole Catalonia. We show that the
interannual variability of summer fires is significantly correlated with
summer precipitation and summer maximum temperature. In addition, fires
are significantly related to antecedent climate conditions, showing
positive correlation with lagged precipitation and negative correlation
with lagged temperatures, both with a time lag of two years, and
negative correlation with the minimum temperature in the spring of the
same year. The interaction between antecedent climate conditions and
fire variability highlights the importance of climate not only in
regulating fuel flammability, but also fuel structure. On the basis of
these results, we discuss a simple regression model that explains up to
76% of the variance of the Burned Area and up to 91% of the variance
of the number of fires. This simple regression model produces reliable
out-of-sample predictions of the impact of climate variability on summer
forest fires and it could be used to estimate fire response to different
climate change scenarios, assuming that climate-vegetation-humans-fire
interactions will not change significantly
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
On the key role of droughts in the dynamics of summer fires in Mediterranean Europe
Get PDFSummer fires frequently rage across Mediterranean Europe, often intensified by high temperatures and droughts. According to the state-of-the-art regional fire risk projections, in forthcoming decades climate effects are expected to become stronger and possibly overcome fire prevention efforts. However, significant uncertainties exist and the direct effect of climate change in regulating fuel moisture (e.g. warmer conditions increasing fuel dryness) could be counterbalanced by the indirect effects on fuel structure (e.g. warmer conditions limiting fuel amount), affecting the transition between climate-driven and fuel-limited fire regimes as temperatures increase. Here we analyse and model the impact of coincident drought and antecedent wet conditions (proxy for the climatic factor influencing total fuel and fine fuel structure) on the summer Burned Area (BA) across all eco-regions in Mediterranean Europe. This approach allows BA to be linked to the key drivers of fire in the region. We show a statistically significant relationship between fire and same-summer droughts in most regions, while antecedent climate conditions play a relatively minor role, except in few specific eco-regions. The presented models for individual eco-regions provide insights on the impacts of climate variability on BA, and appear to be promising for developing a seasonal forecast system supporting fire management strategies.We thank the European Forest Fire Information System-EFFIS (http://effis.jrc.ec.europa.eu) of the European
Commission Joint Research Centre for the fire data. We acknowledge the SPEI data providers (http://sac.csic.
es/spei/database.html). Special thanks to Joaquín Bedia, Esteve Canyameras, Xavier Castro and Andrej Ceglar
for helpful discussions on the study. This work was partially funded by the Project of Interest “NextData” of the Italian Ministry for Education, University and Research and by the EU H2020 Project 641762 “ECOPOTENTIAL: Improving Future Ecosystem Benefits through Earth Observations”. Ricardo Trigo was supported by IMDROFLOOD funded by Portuguese FCT (WaterJPI/0004/2014).Peer ReviewedPostprint (published version
Climate change impacts on wildfires in a Mediterranean environment
Get PDFWe analyse the observed climate-driven changes in summer wildfires and
their future evolution in a typical Mediterranean environment (NE
Spain). By analysing observed climate and fire data from 1970 to 2007,
we estimate the response of fire number (NF) and burned area (BA) to
climate trends, disentangling the drivers responsible for long-term and
interannual changes by means of a parsimonious Multi Linear Regression
model (MLR). In the last forty years, the observed NF trend was
negative. Here we show that, if improvements in fire management were not
taken into account, the warming climate forcing alone would have led to
a positive trend in NF. On the other hand, for BA, higher fuel
flammability is counterbalanced by the indirect climate effects on fuel
structure (i.e. less favourable conditions for fine-fuel availability
and fuel connectivity), leading to a slightly negative trend. Driving
the fire model with A1B climate change scenarios based on a set of
Regional Climate Models from the ENSEMBLES project indicates that
increasing temperatures promote a positive trend in NF if no further
improvements in fire management are introduced
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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