Search results for "URBAN AREA"
showing 10 items of 144 documents
An Application of Analytic Network Process in the Planning Process: The Case of an Urban Transformation in Palermo (Italy)
2014
The primary objective of this study is to test the multicriteria analysis application in favor of a selection process among alternative transformations of an urban area in the city of Palermo. The choice is referred to as a strategyoriented one aiming to create “new urban centralities” able to redraw all urban structures that start to activate renewal processes within the existing city. The application of multicriteria analysis technique, such as the Analytic Network Process (ANP) - BOCR model, is due to the need to represent the complexity of the decision problem characterized by interrelations among several elements described by many indicators from different levels. The case study is als…
Origin of atmospheric aerosols at the Pierre Auger Observatory using studies of air mass trajectories in South America
2014
The Pierre Auger Observatory is making significant contributions towards understanding the nature and origin of ultra-high energy cosmic rays. One of its main challenges is the monitoring of the atmosphere, both in terms of its state variables and its optical properties. The aim of this work is to analyze aerosol optical depth $\tau_{\rm a}(z)$ values measured from 2004 to 2012 at the observatory, which is located in a remote and relatively unstudied area of the Pampa Amarilla, Argentina. The aerosol optical depth is in average quite low - annual mean $\tau_{\rm a}(3.5~{\rm km})\sim 0.04$ - and shows a seasonal trend with a winter minimum - $\tau_{\rm a}(3.5~{\rm km})\sim 0.03$ -, and a sum…
Mass levels, crustal component and trace elements in PM10 in Palermo, Italy.
2007
Abstract Results concerning the levels and elemental compositions of daily PM 10 samples collected at four air quality monitoring sites in Palermo (Italy) are presented. The highest mean value of PM 10 concentrations (46 μg m −3 , with a peak value of 158 μg m −3 ) was recorded at the Di Blasi urban station, and the lowest at Boccadifalco station (25 μg m −3 ), considered as a sub-urban background station. Seventeen elements (Al, As, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Sr, U, V, Zn) were measured by ICP-MS. Al and Fe showed the highest concentrations, indicating the significant contribution of soil and resuspended mineral particles to atmospheric PM 10 . Ba, Cr, Cu, Mn, Mo, Ni, Pb, …
Temporal variability of airborne bacterial community structure in an urban area
2006
International audience; Temporal airborne bacterial genetic community structure and meteorological factors were analysed above an urban area in the northwest of France from December 2003 to April 2004 with a sampling strategy considering different time intervals (from an hour to a month). Principal component analysis (PCA) of B-ARISA (Bacterial-Automated Ribosomal Intergenic Spacer Analysis) profiles revealed a hierarchy in the temporal variability of bacterial community: daily<weekly<seasonal. Co-inertia analysis between B-ARISA data and meteorological factors demonstrated the correlation between the seasonal variability in the bacterial community and climatic conditions such as temperatur…
Application of aerosol optical properties to estimate aerosol type from ground-based remote sensing observation at urban area of northeastern China
2015
Abstract Aerosol optical properties were derived from ground-based sunphotometer observations between 2009-2013 at three urban sites of Shenyang, Anshan, Fushun in northeastern China. The annual means for extinction aerosol optical depths (EAOD) at 500 nm were 0.57±0.38, 0.52±0.35, and 0.41±0.31 at Shenyang, Anshan, Fushun, respectively. The corresponding annual means for the extinction Angstrom exponents (EAE) computed for the wavelengths of 440 and 870 nm were 0.86±0.32, 0.86±0.34 and 0.91±0.35, respectively, indicating that urban area of Northeast China were affected by both coarse and fine particles. Hygroscopic growth in summer and incursions of dust aerosols in spring were evidently r…
Effects of Urbanization on the Temperature Inversion Breakup in a Mountain Valley with Implications for Air Quality
2014
AbstractMany cities located in valleys with limited ventilation experience serious air pollution problems. The ventilation of an urban valley can be limited not only by orographic barriers, but also by urban heat island–induced circulations and/or the capping effect of temperature inversions. Furthermore, land-use/-cover changes caused by urbanization alter the dynamics of temperature inversions and urban heat islands, thereby affecting air quality in an urban valley. By means of idealized numerical simulations, it is shown that in a mountain valley subject to temperature inversions urbanization can have an important influence on air quality through effects on the inversion breakup. Dependi…
Carbon Stocks in Peri-Urban Areas: A Case Study of Remote Sensing Capabilities
2014
Peri-urban areas are the extension of cities into contiguous areas, where households and farms coexist. Carbon stocks (CSs) assessment, a concept here extended to urban features, has not yet been studied in depth over peri-urban areas due to uncertainties in such CSs quantification, level of detail required about construction materials, and the high spatial variability of those stocks. Remote sensing (RS)-based techniques have been successfully utilized in urban areas for assessing phenomena such as soil sealing, sprawl patterns, and dynamics of surface imperviousness, especially focusing on land cover classification at high to medium spatial scales. Over the floodplain study area of Emilia…
Lichens Used as Monitors of Atmospheric Pollution Around Agadir (Southwestern Morocco)—A Case Study Predating Lead-Free Gasoline
2011
More than 30 epiphytic lichens, collected in Agadir (Morroco) and along a 150-km transect from the Atlantic Ocean eastward, were analyzed for their metal content and lead isotopic composition. This dataset was used to evaluate atmospheric metal contamination and the impact of the city on the surrounding area. The concentrations of Cu, Pb, and Zn (average ± 1 SD) were 20.9 ± 15.2 μg g−1, 13.8 ± 9.0 μg g−1, and 56.6 ± 26.6 μg g−1, respectively, with the highest values observed in lichens collected within the urban area. The 206Pb/207Pb and 208Pb/207Pb ratios in the lichens varied from 1.146 to 1.186 and from 2.423 to 2.460, respectively. Alkyllead-gasoline sold in Morocco by the major petrol …
Dasymetric distribution of votes in a dense city
2017
[EN] A large proportion of electoral analyses using geography are performed on a small area basis, such as polling units. Unfortunately, polling units are frequently redrawn, provoking breaks in their data series. Previous electoral results play a key role in many analyses. They are used by political party workers and journalists to present quick assessments of outcomes, by political scientists and electoral geographers to perform detailed scrutinizes and by pollsters and forecasters to anticipate electoral results. In this paper, we study to what extent more complex geographical approaches (based on a proper location of electors on the territory using dasymetric techniques) are of value in…
Bryophyte investigations in urban areas: diversity of bryoflora of Erice town.
2016
This work is part of a study of bryophyte floras of Sicilian towns that has highlighted the presence in these environments of interesting taxa from the taxonomic and phytogeographical point of view (1, 2, 3, 4). Given its location, perched at 750 m a.s.l. on the S. Giuliano Mount at the northwestern tip of Sicily, the town of Erice has a climate which, although typically Mediterranean, has a strong wet connotation for the frequent presence of fog, especially in the winter time. These features contribute to creating conditions particularly suited to host bryophytes that grow both on artifacts and on phorophytes present in the city and specially in the Balio urban park. The study has allowed …