Search results for " Canyon"

Evaluation of Local Scale PM Pollution Levels in Typical Street Canyon in Riga

2013

The present study describes long term PM10 and PM2.5 changes in typical street canyon with particular emphasis on seasonal, diurnal variations in context with meteorological data. In order to understand PM10 pollution sources during 28 April 2007-31 December 2007, chemical composition measurements were done with particular emphasis on heavy metals (As, Cd, Ni, and Pb), crustal material (Ca, Mg, Na, and K) and anions (sulphates, nitrates, chlorides). Meteorological data used for this evolutional analysis were measured close to traffic related stations and several meteorological parameters were analyzed in relation to particulate measurements. Keep in mind that atmospheric aerosols are genera…

Identità paesaggistica del centro storico di Modica

2016

Il centro storico di Modica si sviluppa lungo il margine orien- tale dell’Avampaese ibleo, un horst calcareo allungato in senso NE-SW che rappresenta il margine settentrionale della placca africana. Il plateau ibleo è attraversato da numerose faglie va- riamente orientate a costituire un sistema di canyon, localmente denominati “cave”, attraversati da corsi d’acqua alimentati da sorgenti carsiche, uno dei quali è il torrente Modica – Scicli, sulle cui pareti si inerpica il centro storico di Modica.

High Resolution Dispersion Modeling near Tunnel Exits

1996

This contribution is concerned with a critical problem which usually occurs at motortraffic tunnels within towns. All exhaust gases accumulating along the entire tunnel distance readily leave the tunnel exits in a very concentrated form. Since modern urban traffic management affords more and more tunnel constructions within highly built-up areas, a reliable calculation of the resulting immission distribution in the neighbourhood of tunnel exits is of great importance.

Submarine canyons of north-western Sicily(Southern Tyrrhenian Sea): Variability in morphology, sedimentary processes and evolution on a tectonically …

2014

Bathy-morphological analysis of submarine canyons across the north-western Sicily continental slope

2016

We present here the results of the morpho-bathymetric analyses of the main submarine canyons along the upper slope off the north-western Sicily. This region developed during the Neogene as the transition area between the Sicilian fold and thrust belt and the Tyrrhenian basin realm. Along the upper slope, a dense network of submarine canyon develops from 80 m water depth up to more than 2000 m, showing a large variability of sizes and morphology. In this area submarine canyons play a crucial role related to the along-slope sedimentary transport and are among the most distinctive features of the submarine seascape. This study is based on a quantitative analysis of a high resolution multibeam …

Controlli stratigrafici e tettonici sull'evoluzione morfo-sedimentaria dell'offshore della Sicilia nord-occidentale durante il Quaternario

2013

Development, human impact and habitat distribution in submarine canyons of the Central and Western Mediterranean

2015

We present in this paper different studies on canyon systems, adopting distinct approaches, temporal and spatial scales. Most of our study areas coincide with the NW Sicilian canyons, which present striking differences in their morphologies in response to the Plio-Quaternary tectonic evolution of the northern Sicilian margin. In the present-day, active sedimentary processes inferred from bedform analyses along some of the studied canyons could drive to enhanced biological activities along them. This is also confirmed by an on-going study of the impact of trawling fishery on the morphology and sedimentary environments of the Sicilian margin, where intense deep-sea bottom trawling activities …

Future coastal hazard scenarios. A case study in NE Sicily (Italy)

2012

The coastal dynamics is the result of several causes that contribute to change the balance of beach deposits over time. The beach system is not always able to maintain coastal balance: the factors contributing to this phenomenon are to be found in both natural and anthropogenic spheres. In this context we present the analysis of marine geology and coastal geomorphological data of a sector between Rocca di Caprileone and Tindari (north-eastern Sicily) with the aim to: i) determine their onland-offshore area relationships, ii) analyze which natural features may contribute to coastal retreat, iii) present coastal hazard scenarios. Until fifty years ago the natural balance of this coastal area …

Geomorphology and speleogenesis of the Vallone Ponte-Grotte d'Acqua karst system (Sant'Angelo Muxaro - Southern Sicily

2010

TRAFFIC FLOW HYPOTHETICAL MODELLING FOR AIR QUALITY IMPROVEMENT AND PLANNING PURPOSES

2019

The main emphasis of this research was to describe air pollution level and dispersion in a typical street canyon (Valdemara Street in Riga (Latvia) city centre), afterward to postulate potential development scenarios and perform modelling in order to understand the influence on air pollution level. For this purpose special mathematical model was used - Operational Street Pollution Model (OSPM), which was developed by the National Environmental Research Institute in Denmark. Following development scenarios were tested: (1) realistic environmentally friendly - decrease of traffic flow by 50 %, as according to street interviews about 36 - 50 % of drivers are ready to change driving habits from…