Evidence of a warm, salty surface current flowing poleward along the Iberian Peninsula is presented using a sequence of satellite infrared images and concomitant in situ hydrographic data obtained during the winter of 1983–1984. The current, which flows over 1500 km along the upper continental slope‐shelf break zone off western Portugal, northwest and northern Spain, and southwest France, is 25–40 km wide, about 200 m deep, and characterized by velocities of 0.2–0.3 m s−1. According to the hydrographic data acquired during late November and early December 1983, the current's salinity signal off Portugal is about 0.2 practical salinity units, and its waters are ∼0.5°C warmer than the surrounding ones. The satellite observations, however, which span a longer time period and cover a much larger area, indicate that the current's typical thermal signature is 1°–1.5°C. The current's associated geostrophic volume transports show an increase from about 300×103 m3 s−1 near 38°3′N to 500–700×103 m3 s−1 at 41°–42°N. The origin of this poleward flow and the causes for its increasing transport off western Iberia are investigated. Onshore Ekman convergence induced by southerly winds along the Portuguese west coast provides about one fifth of the computed transports in the correct direction. A mechanism giving better quantitative agreement with the observations is the geostrophic adjustment of the eastward oceanic flow driven by the large‐scale meridional baroclinic pressure gradient in the eastern North Atlantic as the flow reaches the continental slope of the western Iberian Peninsula. Topographic trapping by the bathymetric step existing along the shelf break explains both the width and the path of the observed current. The role of “dam break” type mechanisms is discarded owing to strong discrepancies between the available models and the present observations. Since satellite images reveal that similar situations occurred during many winters, the flow identified here appears as a characteristic feature of the winter circulation off southwest Europe. Furthermore, the occurrence of analogous poleward flows in eastern boundary layers of the subtropical and mid‐latitude oceans suggests that these currents are typical features of those regions' winter circulation.

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Soil salinization affects 1-10 billion ha worldwide, threatening the agricultural production needed to feed the ever increasing world population. Phytoremediation may be a cost-effective option for the remediation of these soils. This review analyzes the viability of using phytoremediation for salt-affected soils and explores the remedial mechanisms involved. In addition, it specifically addresses the debate over plant indirect (via soil cation exchange enhancement) or direct (via uptake) role in salt remediation. Analysis of experimental data for electrical conductivity (ECe) + sodium adsorption ratio (SAR) reduction and plant salt uptake showed a similar removal efficiency between salt phytoremediation and other treatment options, with the added potential for phytoextraction under non-leaching conditions. A focus is also given on recent studies that indicate potential pathways for increased salt phytoextraction, co-treatment with other contaminants, and phytoremediation applicability for salt flow control. Finally, this work also details the predicted effects of climate change on soil salinization and on treatment options. The synergetic effects of extreme climate events and salinization are a challenging obstacle for future phytoremediation applications, which will require additional and multi-disciplinary research efforts.

[1] A description of the near-surface circulation and its properties is the result of the analysis of a drifting buoy data set in the eastern North Atlantic between the Iberian Peninsula, the Azores, and the Canary Islands. World Ocean Circulation ExperimentTropical Ocean-Global Atmosphere experiment drifters equipped with holey sock drogues centered at 15 m depth collected a total of 14.4 years of data. The drifters sampled a rather inhomogeneous velocity field with a weak mean flow regime and eddies of different scales. They meandered southward everywhere in the study region, except in the Iberian coastal transition zone north of 41°N where they headed northward. The near-surface mean velocity field obtained from the drifter data set shows all important mean currents, including the poleward Portugal Coastal Countercurrent during the fall, winter, and early spring off western and northern Iberia, the southward Portugal Coastal Current, the slow offshore southward flow of the Portugal Current during the whole year, the southwestward Canary Current, and the eastward Azores Current, which extends to the vicinity of the African coast near the Gulf of Cadiz. Maps of the eddy kinetic energy field were obtained from the drifters and from satellite altimetry. It provides the largest part of the total kinetic energy. The rate of dispersion is estimated from the Lagrangian statistics of the drifting buoys. The dispersion of the drifters in the study region is well modeled by a simple description of eddy diffusion assuming homogeneous turbulence. Ensemble mean diffusivities K and the Langrangian integral length scales and timescales (L and T) were obtained for the zonal and meridional directions. The sea surface temperature measured along the drifter trajectories is used to produce estimates of the eddy diffusivity, which is compared with the diffusivity estimates obtained from the theory of Taylor. The eddy diffusivity is found to be approximately proportional to the eddy kinetic energy. Discrete eddies and meanders were observed using drifters and altimetry in order to map and describe their geographical distribution and characteristics in the eastern North Atlantic.

Worldwide volume production and consumption of engineered composite materials, namely fiber reinforced polymers (FRP), have increased in the last decades, mostly in the construction, automobile, aeronautic and wind energy sectors. This rising production and consumption have also led to an increasing amount of FRP waste, either end-of-life (EoL) products or manufacturing rejects. Taking into account the actual and impending EU framework on waste management, in which clear targets are set with concrete measures to ensure effective implementation, landfill and incineration will be progressively unavailable as traditional end-routes for this kind of waste. Recycling techniques and end-use applications for the recyclates have been investigated over the past twenty years, but even so, more cost-effective and feasible market outlets for the recyclates should be identified that meet both the economic and the environmental points of view. This paper is aimed at enclosing and summarizing an update overview regarding all these issues: current legislation, recycling techniques and end-use applications for the recyclates. Additionally, as a case study, the assessment of the potential improvements that could be made on the eco-efficiency performance (sustainability) of a typical FRP composite materials' industry by recycling and re-engineering process approaches is also reported.

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Satellite image sequences (covering periods of a few days throughout the annual cycle) of the waters off southern Iberia have been analyzed in conjunction with concurrent surface wind speed data from coastal stations. Qualitative analysis reveals a large degree of temporal and spatial variability in the thermal signature of the sea surface over periods of both a few days and several months. During the summer, a cool seasurface temperature signature extends from the western Iberian coast around Cape St. Vincent and eastward as far as Faro. At the same time, a warm signature originating on the Iberian coast between Faro and Cadiz extends into the Strait of Gibraltar. These two features are shown to sometimes adopt more westerly positions, and the strait experiences regions of cool thermal signature originating at its southern side. During winter, the surface flow into the Mediterranean through the Strait of Gibraltar is anomalously warm and appears to come from the interior of the Gulf of Cadiz. Quantitative measurements show that temporal variability over timescales of a few days at individual sites is maximum in midsummer. Spatial thermal variability over the whole region is found to peak toward the end of the summer. Statistical analyses of the data reveal the coupling between the surface wind field in the Gulf of Cadiz and the surface thermal pattern (especially during the summer). Wind‐induced, across‐stream upwelling in the Strait of Gibraltar, although dynamically subordinate to tidal and density‐driven processes, is shown to occasionally dominate the surface thermal signature.