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Giuseppe Montana Luciana Randazzo Ilaria A. Oddo Mariano Valenza 《Environmental Geology》2008,56(2):367-380
Chemical, mineralogical and isotopic composition (34S/32S) analyses were carried out on “black crusts” developed on the old buildings of Palermo (Sicily) with the aim to distinguish
between natural and anthropogenic sulphur sources. Furthermore individual samples of total suspended particulate (TSP) were
collected and analysed in order to estimate the influence of air pollution on the decay process of calcareous stones in a
typical southern Mediterranean coastal environment. SEM/EDS analysis, X-ray diffractometry, IR spectroscopy and liquid chromatography
led to the compositional characterization of “black crusts” and airborne particulate matter in the city. Sulphur isotopic
compositions of gypsum-bearing crusts showed a prevailing contribution of anthropogenic sources (vehicle exhaust and other
combustion processes). Natural sulphur and/or sulphate sources (biogenic and/or sea-spray) were shown to play a secondary
role. These data can be considered a starting point for the determination of the rate of growth of “black crusts” in a coastal
Mediterranean urban environment like Palermo. In the future, they might be useful to local authorities for planning more efficient
maintenance action in order to slow as much as possible the rate of decay of the monumental heritage of the city. 相似文献
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C. Dubois S. Somot S. Calmanti A. Carillo M. Déqué A. Dell’Aquilla A. Elizalde S. Gualdi D. Jacob B. L’Hévéder L. Li P. Oddo G. Sannino E. Scoccimarro F. Sevault 《Climate Dynamics》2012,39(7-8):1859-1884
Within the CIRCE project “Climate change and Impact Research: the Mediterranean Environment”, an ensemble of high resolution coupled atmosphere–ocean regional climate models (AORCMs) are used to simulate the Mediterranean climate for the period 1950–2050. For the first time, realistic net surface air-sea fluxes are obtained. The sea surface temperature (SST) variability is consistent with the atmospheric forcing above it and oceanic constraints. The surface fluxes respond to external forcing under a warming climate and show an equivalent trend in all models. This study focuses on the present day and on the evolution of the heat and water budget over the Mediterranean Sea under the SRES-A1B scenario. On the contrary to previous studies, the net total heat budget is negative over the present period in all AORCMs and satisfies the heat closure budget controlled by a net positive heat gain at the strait of Gibraltar in the present climate. Under climate change scenario, some models predict a warming of the Mediterranean Sea from the ocean surface (positive net heat flux) in addition to the positive flux at the strait of Gibraltar for the 2021–2050 period. The shortwave and latent flux are increasing and the longwave and sensible fluxes are decreasing compared to the 1961–1990 period due to a reduction of the cloud cover and an increase in greenhouse gases (GHGs) and SSTs over the 2021–2050 period. The AORCMs provide a good estimates of the water budget with a drying of the region during the twenty-first century. For the ensemble mean, he decrease in precipitation and runoff is about 10 and 15% respectively and the increase in evaporation is much weaker, about 2% compared to the 1961–1990 period which confirm results obtained in recent studies. Despite a clear consistency in the trends and results between the models, this study also underlines important differences in the model set-ups, methodology and choices of some physical parameters inducing some difference in the various air-sea fluxes. An evaluation of the uncertainty sources and possible improvement for future generation of AORCMs highlights the importance of the parameterisation of the ocean albedo, rivers and cloud cover. 相似文献
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Ocean Dynamics - Internal tides are studied in the central Mediterranean Sea using observational data and numerical experiments. Both numerical results and observations indicate that the baroclinic... 相似文献
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