Search results for "canyon"
showing 10 items of 33 documents
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
A numerical simulation scheme for the albedo of city street canyons
1985
A numerical scheme is described for the calculation of effective albedo values of long city street canyons. The method is based on a generalization of the radiation model for inclined surfaces recently presented by Bruhl and Zdunkowski (1983). Calculated albedo values are compared with Aida's (1982) experimentally determined results. It is found that experiment and theory are in reasonable and in some cases in excellent agreement. Additional results obtained by varying the geometry of the street canyon as well as the surface reflectivities are shown to demonstrate the versatility of the calculation scheme.
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…
Ultraviolet radiation protection by a beach umbrella.
2010
A beach umbrella intercepts all direct UV irradiance, but only part of the diffuse component. Using a simple sky view factor model, we have determined the fraction of the hemispheric diffuse irradiance that is not intercepted by the umbrella. Assuming a sensor at the surface and close to the center of the umbrella, isotropic diffuse irradiance and for an umbrella of 80 cm radius and 100 cm high, our results show that approximately 34% of the incident horizontal irradiance is not intercepted by the umbrella. These results agree with irradiance measurements conducted with and without the umbrella. The model is next extended to examine receipt of UV radiation by a human figure in a vertical po…