Observations of current rings in the Antarctic Zone at Drake Passage

Time series of current velocity and temperature from several depths at a site near the center of Drake Passage show features that can plausibly be interpreted as current rings. Between June 1975 and January 1976, five cyclonic rings from the Continental Water Boundary and one anticyclonic ring from the Polar Front passed over the site. The diameters of the rings varied from 30 km to 130 km, and all of them extended vertically to a depth of at least 2500 m. The rings exhibited maximum spin velocities of about 20 cm sec−1 at 1000 m depth and 10 cm sec−1 at 2500 m. Their translatory motion, which was toward the north at about 4 cm sec−1, contained a westward component relative to the ambient flow. The magnitude of the westward component suggests that it may have resulted from an interaction between rings and the sea floor, which slopes downward to the northeast at the mooring site. The total available mechanical energy of the rings (kinetic plus potential) varied from 6.2 × 1013 j in the smallest ring to 9.9 × 1014 in the largest. The available heat, relative to the Antarctic Zone, was several orders of magnitude larger: −3.0 × 1017 j for the smallest ring and −3.6 × 1018 j for the largest. The numbers indicate that current rings may play an important role in dissipating the kinetic energy of the circumpolar fronts and that they may be responsible for a significant poleward flux of heat in the Southern Ocean

Studio idrogeologico del bacino del rio di Santa Caterina di Pittinuri(Cuglieri, Sardegna Centro-Occidentale)

The catchment area of the river Santa Caterina is located in western part of Montiferru, one of most important volcanic complex of Sardinia. In order to determine the water balance of the basin, the base flow rates of streams and springs were measured for the purpose of assessing groundwater reservoirs and dynamic storage by means of depletion law of hydrogeologic system. Because of the prevalence of volcanics rocks a study of lava flow and fracture systems was required to determine the main directions of growndwater flow. It was found that hydrogeologic and hydrographic watershed do not coincide. In fact a fair amount of water out flow through bedding planes various lava flows

A methodological framework for the economic assessment of ict-tools for occupants’ engagement

The concept of smartness in building dates to the 1970s, but, in face of the breakthrough technological developments, a new notion of smart building is currently recognized. We talk about ambient intelligence, referring to a building which is responsive to the needs of the occupants and of the energy system. An ambient-intelligent building is human-centric; new services and interfaces are provided to the buildings occupants to learn and set their preferences, with a positive impact on their comfort level and satisfaction with the indoor environmental quality. ICT and IoT are part of the enabling technologies to exploit the potentials of smart buildings, by unlocking the capability of buildings to interact with the system they belong to. To bolster the diffusion of new technologies, methodologies to get quantitative results proving their effectiveness should be provided. In this paper the application of a well-established economic evaluation tool, the so-called Cost-Benefit Analysis, to the case of the deployment of new ICT-tools for occupants’ engagement is presented. The methodology is adopted within the H2020 Mobistyle project, where two levels of the evaluation are identified: the whole project level and the single demo case one. The purpose of the methodology is to assess the effectiveness of the adoption of the ICT-tools in producing economic value in terms of benefits for the occupants and the society. Some preliminary results of its application to the Italian case study are also presented, showing a positive socio-economic balance since the beginning of the deployment

Dominance-based rough set approach and analytic network process for assessing urban transformation scenarios

For half a century, the significant development of intensive farming has led to a massive use of products such as pesticides. The excessive use of these substances has contaminated surface water and groundwater. Drinking water extraction points have also had to be abandoned. Some thirty years ago, in the southwest of France, a group of farmers decided to improve their farming methods, as well as developing new Best Environmental Practices, such as grass strips along streams and riparian forests. By combining the use of ELECTRE TRI-C multi-criteria model with a GIS, we were able to characterise the contribution of each farming area to the risk of surface water contamination with pesticides. We also assessed the effectiveness of different environmental practices. We found that the use of Best Environmental Practices led to a reduction in the risk of pesticides transfer. This methodology re-enforces decision support tools for water resource managers and agricultural and environmental stakeholders

On the Choquet multiple criteria preference aggregation model: theoretical and practical insights from a real-world application

We consider the use of the Choquet integral for evaluating projects or actions in a real-world application starting from the case of the re-qualification of an abandoned quarry. Despite the Choquet integral being a very well-known preference model for which there is a rich and well developed theory, its application in a multiple criteria decision aiding perspective requires some specific methodological developments. This led us to work out and implement, in practice, two new procedures: A first procedure to build interval scales with the objective of assigning utility values on a common scale to the criteria performances, and a second one to construct a ratio scale for assigning numerical values to the capacities of the Choquet integral. This article discusses the strengths and weaknesses of the Choquet integral as appearing in the case study, proposing as well insights related to the interaction of the experts within a focus grou

An analysis of upwelling off the south-east Arabian coast during the summer monsoon

A method is described for determining the absolute dynamic topography of the sea surface. Using hydrographic and wind data obtained in 1963, the surface topography and the horizontal and vertical mass transports off the southeast Arabian coast during the summer monsoon are calculated. As indicated by the calculations, upwelling occurs throughout a region extending at least 400 km offshore and paralleling the Arabian coast for over 1000 km. Upwelling is most intense in a narrow band adjacent to the coast. Because of the great breadth of the upwelling zone, the upwelled water is supplied from levels considerably deeper than those observed elsewhere in coastal upwelling areas

Evolution of iron speciation during hydration of C4 AF

International audienceIt is now well accepted and demonstrated that calcium silicate, calcium aluminate and calcium sulfo aluminate (ettringite, AFm) phases exhibit a good capability to fix metals and metalloids. Unfortunately the role of minor phases and especially calcium-ferric aluminate phase, shorthand C(4)AF is not well defined. In other systems like in soils or sediments iron phases play a key role in the fixation of pollutant. In cement sorption isotherms, indicated that various metals can be retained by the C(4)AF hydrated products. Therefore the capabilities of those phase to retain heavy metal should not be neglected. Previous investigations have shown that the minerals formed during the hydration of C(4)AF are similar to those formed from C3A (pure tri-calcium aluminate) under comparable conditions. Nevertheless no investigation was conducted at the molecular level and there is still a controversy whether Fe substitutes for Al in the hydrated minerals in whole or in part, or if it forms FeOOH clusters scattered throughout the matrix. In this context we have conducted XAS experiments using synchrotron radiation. It was found that the hydration of C(4)AF forms C(3)AH(6) (hydrogarnet) in which Fe randomly substitutes for Al as well as an amorphous FeOOH phase. Intermediate products like AFm (i.e., an ill organized lamellar phase) are also formed but rapidly evolve to C(3)AH(6); iron does not seem to be incorporated in the AFm structure