143 research outputs found
Modelling studies of wind field on urban environment
International audienceIncreasing load of air pollution in urban environment emphasises the need for detailed evaluation of wind characteristics that significantly affect the air quality of urban areas, especially, in large agglomerations. This paper includes analysis of urban wind climatology and estimation of wind profiles based on measurements of the new urban climate station located at the Eötvös University, observations of the meteorological station network of the Budapest agglomeration area, and multi-level wind measurements near Hegyhåtsål. Furthermore, wind field modelling (using the WAsP linear spectral wind flow model) is presented over selected representative complex areas that demonstrates strong dependence between wind, height, topography, and roughness
Regional climate change impacts on wild animals' living territory in Central Europe
In this paper the projected future impact of climate change has been analyzed for the quality of
living conditions of the European terrestrial vertebrates (amphibians, reptiles, birds, mammals) in the
Carpathian Basin. According to the climate scenarios, warmer and drier climatic conditions are likely to
occur in the Carpathian Basin by end of this century. Simultaneous analysis of climate parameters,
climate simulations and animal range datasets enables us to evaluate the vulnerability of different
European species to regional warming and climate change. The spatial climate analogy technique is used
to analyze the estimated rapid change of the wild animalsâ habitats and their northward migration. For the
reference climate data of Debrecen is considered, and three spatial analogue regions are compared. The
results suggest that generally a significant decline in habitats is very likely for most of the analyzed
animal groups by the end of the 21st century. The largest rate of decline is estimated for birds. However,
living conditions for reptiles may improve in the future due to the warmer and drier climatic conditions,
which are favourable for these species
Validation of a high resolution version of the regional climate model RegCM3 over the Carpathian Basin
This paper presents a validation study for a high-resolution version of the Regional Climate Model version 3 (RegCM3) over the Carpathian basin and its surroundings. The horizontal grid spacing of the model is 10 kmâthe highest reached by RegCM3. The ability of the model to capture temporal and spatial variability of temperature and precipitation over the region of interest is evaluated using metrics spanning a wide range of temporal (daily to climatology) and spatial (inner domain average to local) scales against different observational datasets. The simulated period is 1961â90. RegCM3 shows small temperature biases but a general overestimation of precipitation, especially in winter; although, this overestimate may be artificially enhanced by uncertainties in observations. The precipitation bias over the Hungarian territory, the authorsâ main area of interest, is mostly less than 20%. The model captures well the observed late twentieth-century decadal-to-interannual and interseasonal variability. On short time scales, simulated daily temperature and precipitation show a high correlation with observations, with a correlation coefficient of 0.9 for temperature and 0.6 for precipitation. Comparison with two Hungarian station time series shows that the model performance does not degrade when going to the 10-km gridpoint scale. Finally, the model reproduces the spatial distribution of dry and wet spells over the region. Overall, it is assessed that this high-resolution version of RegCM3 is of sufficiently good quality to perform climate change experiments over the Carpathian regionâand, in particular, the Hungarian territoryâfor application to impact and adaptation studies
Teleconnections and local weather orchestrate the reproduction of tit species in the Carpathian Basin
The future climate characteristics of the Carpathian Basin based on a regional climate model mini-ensemble
Four regional climate models (RCMs) were adapted in Hungary for the dynamical
downscaling of the global climate projections over the Carpathian Basin: (i) the ALADIN-Climate
model developed by Météo France on the basis of the ALADIN short-range
modelling system; (ii) the PRECIS model available from the UK Met Office Hadley Centre;
(iii) the RegCM model originally developed at the US National Center for Atmospheric
Research, is maintained at the International Centre for Theoretical Physics in Trieste; and
(iv) the REMO model developed by the Max Planck Institute for Meteorology in Hamburg. The
RCMs are different in terms of dynamical model formulation, physical parameterisations;
moreover, in the completed simulations they use different spatial resolutions, integration
domains and lateral boundary conditions for the scenario experiments. Therefore, the results
of the four RCMs can be considered as a small ensemble providing information about various
kinds of uncertainties in the future projections over the target area, i.e., Hungary.
After the validation of the temperature and precipitation patterns against measurements, mean
changes and some extreme characteristics of these patterns (including their statistical
significance) have been assessed focusing on the periods of 2021–2050 and 2071–2100
relative to the 1961–1990 model reference period. The ensemble evaluation indicates that the
temperature-related changes of the different RCMs are in good agreement over the Carpathian
Basin and these tendencies manifest in the general warming conditions. The precipitation
changes cannot be identified so clearly: seasonally large differences can be recognised among
the projections and between the two periods. An overview is given about the results of the
mini-ensemble and special emphasis is put on estimating the uncertainties in the simulations
for Hungary
Novel polylactic acid (PLA)-based active packaging with incorporation of nanoparticles and its performance throughout shelf-life of fresh-cut fruit
This study aimed at developing innovative and environmentally friendly packages for fresh-cut fruits and at a better understanding their effect on physicochemical, mechanical and microbiological characteristics during shelf-life. Packages were developed under the scope of EU project SusFoFlex (7th framework programme) â thought to incorporate materials in final packaging formulations complying environmental and sustainability concerns and valorisation of agri-food by-products. Polylactic acid (PLA)-based active packaging formulations differed in nanoclays used and presence/absence of a surfactant. PLA-nanocomposite packaging performance was evaluated and compared with pristine-PLA and conventional polyethylene terephthalate (PET). Polyone was used as plasticizer in PLA packages. PET formulation did not include any nanoclay. Fresh-cut melon was selected as food model to assess PLA packaging formulations performance on quality changes taking place throughout 7-d storage under controlled conditions. Physicochemical and textural analysis over time encompassed weight loss, colour, visual appearance, pH, soluble solids and firmness, whereas microbial enumeration covered vegetative mesophilics and psychrotrofics, Gram- rods, nonsporing Gram+ rods and cocci, yeasts and moulds. Environmental impact of PLA-based packaging was evaluated via life cycle assessment (LCA) and compared with PET. Under limit storage conditions, all microbial groups exhibited maximum viable counts after 5-d. Pseudomonas aeruginosa and Escherichia coli were absent, and refrigeration proved to effectively reduce microbial activity. Overall inspection of dataset throughout storage, unfolded that nanoclays and surfactants in PLA formulations improved their performance, thus contributing to bring together the characteristics of both biopolymers (PLA and PET). Finally, LCA impact assessment indicated that PLA packaging with nanoclays had the highest environmental performance
Human Perception of Fear in Dogs Varies According to Experience with Dogs
To investigate the role of experience in humansâ perception of emotion using canine visual signals, we asked adults with various levels of dog experience to interpret the emotions of dogs displayed in videos. The video stimuli had been pre-categorized by an expert panel of dog behavior professionals as showing examples of happy or fearful dog behavior. In a sample of 2,163 participants, the level of dog experience strongly predicted identification of fearful, but not of happy, emotional examples. The probability of selecting the âfearfulâ category to describe fearful examples increased with experience and ranged from.30 among those who had never lived with a dog to greater than.70 among dog professionals. In contrast, the probability of selecting the âhappyâ category to describe happy emotional examples varied little by experience, ranging from.90 to.93. In addition, the number of physical features of the dog that participants reported using for emotional interpretations increased with experience, and in particular, more-experienced respondents were more likely to attend to the ears. Lastly, more-experienced respondents provided lower difficulty and higher accuracy self-ratings than less-experienced respondents when interpreting both happy and fearful emotional examples. The human perception of emotion in other humans has previously been shown to be sensitive to individual differences in social experience, and the results of the current study extend the notion of experience-dependent processes from the intraspecific to the interspecific domain
Deferred imitation and declarative memory in domestic dogs
This study demonstrates for the first time deferred imitation of novel actions in dogs (Canis familiaris) with retention intervals of 1.5 min and memory of familiar actions with intervals ranging from 0.40 to 10 min. Eight dogs were trained using the 'Do as I do' method to match their own behaviour to actions displayed by a human demonstrator. They were then trained to wait for a short interval to elapse before they were allowed to show the previously demonstrated action. The dogs were then tested for memory of the demonstrated behaviour in various conditions, also with the so-called two-action procedure and in a control condition without demonstration. Dogs were typically able to reproduce familiar actions after intervals as long as 10 min, even if distracted by different activities during the retention interval and were able to match their behaviour to the demonstration of a novel action after a delay of 1 min. In the two-action procedure, dogs were typically able to imitate the novel demonstrated behaviour after retention intervals of 1.5 min. The ability to encode and recall an action after a delay implies that facilitative processes cannot exhaustively explain the observed behavioural similarity and that dogs' imitative abilities are rather based on an enduring mental representation of the demonstration. Furthermore, the ability to imitate a novel action after a delay without previous practice suggests presence of declarative memory in dogs. © 2013 Springer-Verlag Berlin Heidelberg
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