Search

The electricity production from Renewable Energy (RE) in isolated locations requires long-term energy storage systems. To that end, Hybrid Energy Storage Systems (HESS), through a combination of hydrogen and batteries, can benefit from the different advantages of both technologies. This paper presents a hybrid Power-to-Power (PtP) Optimal Power Dispatch (OPD) model for isolated systems with no electric grid access. Currently, the electricity supply in such cases is usually based on a mix of RE as the primary energy source sustained by a diesel genset acting as a backup generator. In this context, the model delivers the hourly energy flows between renewable production sources, energy storage devices and the electrical load, which minimises costs and Green House Gases (GHG) emissions. For validation purposes, the model was tested through its application to a case study in an isolated area in the Canary Islands, Spain. The results show that the algorithm calculates the hourly OPD successfully for a given plant sizing, considering the defined operational states of the different assets. These operational constraints showed a decrease in the PtP round-trip efficiency of 5.4% and a reduction of the hydrogen production of 9.7%. Finally, the techno-economic analysis of the results proves that the combination of hydrogen and batteries with RE production is a feasible alternative to phasing out fossil fuels for the selected case study – reducing the diesel generator usage down to 1.2% of the yearly energy supply. • Novel multi-state optimal power dispatch model for power-to-power energy systems. • Multi-year techno-economic evaluation of an off-grid case study. • Phasing out fossil fuels with renewable energy-based hybrid energy storage systems. • Hydrogen technology contributes to a lower levelized cost of energy. • High initial investment cost was a significant entry barrier to deploying hydrogen. [ABSTRACT FROM AUTHOR]

So far in the literature, the two-parameter Weibull distribution and its other extensions are frequently implemented to analyze the wind speed energy data sets. However, based on our study of the literature, there is no published work about analyzing the wind speed energy data sets using new probability distributions that are developed via trigonometric functions. In this paper, I attempt to cover this amazing and interesting research gap. Therefore, I incorporate a trigonometric function, especially, the sine function to introduce a new statistical distributional method. The proposed method is called a new modified sine- G family of distributions. Some distributional properties of the new modified sine- G method are obtained. Using the new modified sine- G method, a new extension of the Weibull distribution called a new modified sine-Weibull distribution is studied. The new modified sine-Weibull distribution is applied to analyze four wind speed energy data sets. All three data sets are taken from the weather station at Sotavento Galicia in the Canary Islands, Spain, located at 43.3544 North and 7.8812 West. [ABSTRACT FROM AUTHOR]

This paper analyzes the implementation of corporate sustainability strategies (CSS) in hotels, identifying key factors and practices as perceived by middle-managers. Using qualitative methods, we conducted initial and in-depth interviews with owners, top-managers, and 37 middle-managers from various departments of a hotel chain in the Canary Islands. An existing literature-informed CSS implementation framework guided our analysis, revealing nine key factors that act as drivers, barriers, or both to CSS implementation. We identified crucial practices including paper-use reduction, employee well-being, plastic-use reduction, energy efficiency, recycling, water management, air quality, social contribution, food waste management, and green chemicals, noting varying relevancies across departments. Particularly, work-wellbeing, plastic-use reduction, and energy efficiency showed the highest alignment with CSS. Our findings offer insights into the practical application of CSS, underscoring the importance of tailoring department-specific practices to overarching sustainability goals to bolster organizational sustainability strategies. • Corporate sustainability strategy (CSS) drivers and practices are strongly related to Human Resource Management. • Key drivers for CSS implementation include communication and training, work environment, and corporate commitment and support. • Key barriers of CSS implementation include guest behavior and external issues such as the pandemic crisis. • Relevance and alignment of key practices vary among departments, which need tailored strategies based on their attributes. • Paper-use reduction emerges as the main key practice of CSS, followed by work wellbeing and plastic-use reduction. [ABSTRACT FROM AUTHOR]

After almost 50 years of quiescence, the Cumbre Vieja rift in La Palma underwent a reactivation process that culminated in the eruption of the Tajogaite volcano from September 19 to December 13, 2021. In July 2021, a magnetic station (CFU) was deployed in the western flank of the Cumbre Vieja rift, 2 km away from the site where the eruptive vents would open two months later. In September 2021, a second magnetic station (SAN) was installed near the southern end of the rift. In this paper we study two months of geomagnetic data at CFU before the eruption and three months of geomagnetic data at SAN during the eruption. The analysis of these time series revealed a magnetic signal at the CFU station with an amplitude of 10 nT and a duration of 10 days by mid-August, one month before the eruption onset. We studied possible correlations with other physical parameters (ground deformation, long-period and very-long-period seismic activity) and concluded that this signal could be related to changes in the magnetization of rocks beneath the volcanic edifice caused by magma intrusion and volcanic/hydrothermal fluids circulation preceding the eruption. At the SAN magnetic station, the time series suggests that a slight decrease in the geomagnetic field could reflect the end of the eruptive process. • Three magnetic stations were deployed at La Palma in 2021. • Geomagnetic field time series acquired before/during the 2021 eruption were analyzed. • We identified a volcanomagnetic signal one month before the eruption onset. • This signal had an amplitude of 10 nT and a duration of ∼10 days. • It correlates with ground deformation and long-period seismic activity. [ABSTRACT FROM AUTHOR]

Human occupation of coastal strips generates pressures that can trigger severe degradation processes in marine ecosystems and threaten human livelihoods and the sustainability of the socio-ecological system. In this context, monitoring the conservation status of algal and benthic plant communities, as the basis of coastal ecosystems, is essential for the sustainability of coastal environments. The paper presents a bionomic investigation in a shallow water beach-reef coastal system called Las Canteras, in the Canary Islands (Spain). The work aims to generate a high-resolution mapping, according to standardised rules, of the marine habitats of an area with high ecological value showing signs of severe degradation due to anthropogenic pressure. For this purpose, direct observation techniques were combined with hyperspectral remote sensing techniques. The bathymetric, sedimentological and biological data collected were combined to generate detailed mapping of 13 marine habitats according to the Spanish Inventory of Marine Habitats and Species (IEHEM by its initials in Spanish) classification system. Comparison of these results with previous studies since 1960 shows total regression of the most sensitive species of marine habitats in the Canary Islands, such as Cymodocea nodosa, as well as the decline of sandy substrates which are fundamental for maintenance of the local coastal socio-ecological system. • High-resolution mapping of marine habitats in shallow waters of high ecological value is presented. • Hyperspectral remote sensing techniques and in situ observations have been used. • Information on bathymetry, substrates and benthic communities have been derived and combined. • The decline of key species in the marine ecosystems of the Canary Islands has been observed. [ABSTRACT FROM AUTHOR]

This study addresses the imperative transition towards renewable energy for the powering of desalination technologies, focusing particularly on island contexts. The Canary Archipelago serves as a unique wind energy-desalination laboratory, with numerous experimental projects conducted since the late 1980s. The lessons learnt that are identified in this paper highlight the critical factors influencing project success or failure, including the modernization of desalination plants, the optimal selection of wind farm sites and turbine technology, adequate resources for operating and maintenance tasks, and optimal battery sizing to minimize system shutdowns. In this context, reverse osmosis emerges as the most advantageous technology for variable operating conditions. System interfaces between wind turbines and desalination units are also discussed and it is identified that further research is needed for mechanical or hydrostatic interface systems, while electrical interface systems suit low-medium water demand areas. Recommendations are given for system design and maintenance with the aim of providing valuable information for other island communities grappling with the water-energy nexus and climate change mitigation. [ABSTRACT FROM AUTHOR]

The latest evidence suggests that multi-hazards and their interrelationships (e.g., triggering, compound, and consecutive hazards) are becoming more frequent across Europe, underlying a need for resilience building by moving from single-hazard-focused to multi-hazard risk assessment and management. Although significant advancements were made in our understanding of these events, mainstream practice is still focused on risks due to single hazards (e.g., flooding, earthquakes, droughts), with a limited understanding of the stakeholder needs on the ground. To overcome this limitation, this paper sets out to understand the challenges for moving towards multi-hazard risk management through the perspective of European stakeholders. Based on five workshops across different European pilots (Danube Region, Veneto Region, Scandinavia, North Sea, and Canary Islands) and an expert workshop, we identify five prime challenges: i) governance, ii) knowledge of multi-hazards and multi-risks, iii) existing approaches to disaster risk management, iv) translation of science to policy and practice, and v) lack of data. These challenges are inherently linked and cannot be tackled in isolation with path dependency posing a significant hurdle in transitioning from single- to multi-hazard risk management. Going forward, we identify promising approaches for overcoming some of the challenges, including emerging approaches for multi-hazard characterisation, a common understanding of terminology, and a comprehensive framework for guiding multi-hazard risk assessment and management. We argue for a need to think beyond natural hazards and include other threats in creating a comprehensive overview of multi-hazard risks, as well as promoting thinking of multi-hazard risk reduction in the context of larger development goals. • We identify 5 core challenges for multi-hazard risk assessment and management in Europe. • Governance and knowledge of multi-hazard risk pose the greatest challenges. • Challenges in practices, science-to-policy, and data limit multi-hazard risk management. • We identify ways forward to ease the shift to multi-hazard risk management. [ABSTRACT FROM AUTHOR]

Recovery and analyses of perishable non-charred archaeological wood is extremely rare. Traceological analyses in general are still scarce and mainly focused on waterlogged remains. Ancient desiccated wood from the Canary Islands offers an exceptional opportunity to identify the processes and techniques of the indigenous populations prior to the arrival in the 14th and 15th centuries AD of European colonists. This paper offers xylological and morpho-technological data linked to artefacts recovered in cliffside Prehispanic communal granaries in Gran Canaria (Canary Islands, Spain). The findings gleaned from a combination of xylological and traceological analyses are for the moment the first of their type of the archipelago's indigenous contexts. The data suggest the widespread exploitation of pine (Pinus canariensis) and fig tree (Ficus carica) and advances several analytical categories for wood artefacts and fragments. The identification and description of the different traces is followed by hypotheses as to the technical actions and the nature of the active edges of the stone tools. Thus, work-waste is identified and linked to several technical actions with the aim of reconstructing the chaînes opératoires. Moreover, further experimental research could offer a better understanding of the functions of these wooden artefacts. [ABSTRACT FROM AUTHOR]

The island of Gran Canaria (Canary Islands, Spain) shows great potential for studying the wooden raw materials used by the indigenous population during the Prehispanic period based on xylological analyses from domestic and funerary contexts. This paper includes archaeobotanical data from wooden funerary artefacts recovered from several archaeological contexts of the island and deposited at El Museo Canario (Las Palmas de Gran Canaria, Spain). Our results provide pioneering data as only a few xylological and anthracological analyses have been carried out on this island. Thus, the preferential use of pinewood (Pinus canariensis) for the manufacture of most of the artefacts is suggested, although dragon tree wood (Dracaena sp.) has also been identified in some funerary boards. Wood selection criteria not focusing on healthy wood has been suggested based on a combination of the microscopic observation of fungal decay patterns and archaeoentomological data. In addition to this, morpho-technological analysis suggests extensive woodworking knowledge in a geographic context lacking metal ores. Further xylological and experimental research, including other islands of the archipelago, is needed to obtain a more comprehensive perspective of wood procurement and use during the Prehispanic period. [ABSTRACT FROM AUTHOR]

The Canary Islands are still largely dependent on expensive imported fossil fuels, are stressed by the increasing touristic impact and are extremely vulnerable to climate change due to water scarcity. Water desalinisation is an energy-demanding process and is essential to the sustainable development of these islands. The aim of this study is to explore the potential advantages of a hybrid installation, exploiting two different renewable energy sources, specifically waves and solar, to supply a large desalination plant in Tenerife. The paper ultimately provides a generally applicable procedure for the design of hybrid installations, including three steps: the assessment of available renewable energy sources, the optimal combination of these sources and finally the economic assessment. The wave and solar resources are assessed first, then the hybrid installation is conceptually designed, proposing a criterion for the optimal mixing of the renewable energy sources that can be applied to other resources and other sites. The basic idea is to maximise the exploitation of the renewable power, minimizing the need of the fossil-based back-up system. The costs of the hybrid installation are finally assessed considering the sensitivity to government incentives, showing that the project parity point is reached within the lifetime of typical desalination plants (i.e. 40 years) and can be significantly more attractive in case of Feed-In-Tariffs available in other European countries. [ABSTRACT FROM AUTHOR]

The case study of the Canary Islands (Spain) considered in this paper involves the historical problem of resolving the demand for freshwater. After many years, the focus in the islands turned towards seawater desalination processes to provide safe water for, above all, its citizens, agriculture, and tourism. Due to the high demand for freshwater, the Canary Islands have been a world pioneer in desalination issues, improving the techniques and materials used. While several desalination technologies are available, today the most used worldwide is reverse osmosis. The major drawback of desalination is the high energy cost that the process requires. To this can be added the peculiarities of the electricity generation system in the Canary Islands, which generates more emissions per unit of energy produced compared with the system in mainland Spain. In this study, we selected a desalination plant located on the island of Tenerife, specifically in the municipality of Granadilla de Abona and, after determining its technical characteristics, calculated its ecological footprint. For this, we performed various calculations, including the carbon fixing capacity of forests in the Canary Islands (expressed per hectare) and the total amount of emissions produced in the generation of energy to feed the desalination plant. [ABSTRACT FROM AUTHOR]

In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles ( Caretta caretta ) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑ PCBs, 28.45 vs. 1.12 ng/ml; ∑ OCPs, 1.63 vs. 0.19 ng/ml; ∑ PAHs, 13.39 vs. 4.91 ng/ml; p < 0.001 in all cases). This is the first time that levels of PAHs are reported in the Adriatic loggerheads. With respect to inorganic contaminants, although the differences were not as great, the Adriatic turtles appear to have higher levels of some of the most toxic elements such as mercury (5.74 vs. 7.59 μg/ml, p < 0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants. [ABSTRACT FROM AUTHOR]

Diel Vertical Migration (DVM) in marine ecosystems is performed by zooplankton and micronekton, promoting a poorly accounted export of carbon to the deep ocean. Major efforts have been made to estimate carbon export due to gravitational flux and to a lesser extent, to migrant zooplankton. However, migratory flux by micronekton has been largely neglected in this context, due to its time-consuming and difficult sampling. In this paper, we evaluated gravitational and migratory flux due to the respiration of zooplankton and micronekton in the northeast subtropical Atlantic Ocean (Canary Islands). Migratory flux was addressed by calculating the biomass of migrating components and measuring the electron transfer system (ETS) activity in zooplankton and dominant species representing micronekton ( Euphausia gibboides , Sergia splendens and Lobianchia dofleini ). Our results showed similar biomass in both components. The main taxa contributing to DVM within zooplankton were juvenile euphausiids, whereas micronekton were mainly dominated by fish, followed by adult euphausiids and decapods. The contribution to respiratory flux of zooplankton (3.4 ± 1.9 mg C m −2 d −1 ) was similar to that of micronekton (2.9 ± 1.0 mg C m −2 d −1 ). In summary, respiratory flux accounted for 53% (range 23–71) of the gravitational flux measured at 150 m depth (11.9 ± 5.8 mg C m −2 d −1 ). However, based on larger migratory ranges and gut clearance rates, micronekton are expected to be the dominant component that contributes to carbon export in deeper waters. Micronekton estimates in this paper as well as those in existing literature, although variable due to regional differences and difficulties in calculating their biomass, suggest that carbon fluxes driven by this community are important for future models of the biological carbon pump. [ABSTRACT FROM AUTHOR]

Tourism represents a significant portion of the total economic activity of many islands throughout the world. This high level of tourist activity has a substantial impact on the energy and water demand. Previous research into smart energy systems on islands has demonstrated that there is significant potential for hotels to partake in energy demand shifting. However, the total potential of such shifting is influenced by variables such as air temperature and the level of occupancy of the hotels. The objective of this work is to quantify the sensitivity of these parameters and their impact on the overall effectiveness of demand shifting within hotels. The assessment contained within this paper utilises Mixed Integer Linear Programming to determine the dispatch of supply and demand on a case study hotel in the Canary Islands. The results show that highest reduction of fossil fuels is reached in a fully electrified hotel energy system. The potential is assumed as independent from weather and guests' behaviour. If only PV is used, demand shifting in only one hotel leads to a relative change of the degree of self-sufficiency of 1.6–1.8% but the results visualise a saturation effect for an already high share of renewable energies. • Demand response potential of touristic facilities through coupling electricity and thermal energy systems is shown. • Probabilistic time-series are used to quantify expected mean and deviation. • Both, integration of a trigeneration systems and a fully electrified energy system show highest potentials. • Saturation effect of demand response potential for high shares of renewable energy is observed. [ABSTRACT FROM AUTHOR]

This paper analyses the influence of the variation of meteorological and operational parameters on estimation of the power output of a dispatchable wind farm (WF). The active power set-points (APSPs), established to regulate the wind farm power output (WFPO), are one of the analysed parameters. The WF considered as case study is integrated in the Gorona del Viento wind-hydro power plant (El Hierro-Canary Islands-Spain), which supplies the primary energy demand of the island. Statistical inference between the errors generated by different WFPO estimation models, each fed with different input features, is performed. These models are based on supervised machine learning (ML) regression algorithms, namely support vector regression, random forest, and a combination of the strengths of these two base learning algorithms constructed using stacked regression ensemble techniques. From the results obtained, the following conclusions are drawn: a) There is a marked difference between the errors obtained with the model that only considers wind speed and direction and that which additionally incorporates the APSP parameter, showing the importance of considering this particular parameter; b) the model which incorporates air density and turbulence intensity in addition to the APSP improves the values of all the metrics, independently of the ML technique employed. • The active power set-point (APSP) parameter is very important in WFPO estimation. • Air density, turbulence intensity and APSP parameters improve WFPO estimation. • Eight models are compared for wind farm power output (WFPO) estimation. • Three machine learning techniques implemented in the models are analysed. • Non-parametric statistical inference is used to compare the models. [ABSTRACT FROM AUTHOR]

This paper investigates the challenges isolated islands face in transitioning from fossil fuel-based electricity generation to renewable energy sources. The Canary Islands serve as a case study, where photovoltaic and wind power are the primary renewables, but their variability requires a deep techno-economic analysis. The island's energy demand is predicted to rise by 100% due to economic growth, electrification and electric vehicles. However, implementing renewable systems encounters obstacles, such as limited suitable sites and protected areas. The study uses Wilks' methodology and Monte Carlo sampling to explore 59 combinations of randomly selected inputs of the uncertain variables, aiming for a 95/95% coverage and confidence level in the results. In most cases, they experience energy shortages, failing to meet electric demand. Even though a new generation mix appears to cover demand under all circumstances, the uncertainty unveils a different reality, leading to an approximate 25% increase in system costs. Surpluses in energy generation, while seemingly positive, can pose challenges. The new system's Levelized Cost of Energy increases from around 14 to 17c€/kWh. These cost increases are contingent upon future performance and the variability of uncertain parameters, leading to excesses ranging from slightly below 25% to over 40%. • Demand coverage scenario designed to meet electric demand through renewable sources. • Uncertainty analysis of a scenario for the complete electrification of the economy. • Best Estimate Plus Uncertainty analysis implementing the Wilks' methodology. • Resizing the system to cover the demand with 95% coverage and confidence levels. • Differences in using deterministic and stochastic methods for electric demand coverage. [ABSTRACT FROM AUTHOR]

The Canary Islands' economy is extremely dependent on sea transport. Since accessibility and connectivity are major determinants of international transport costs, the analysis of their main ports' connectivity is crucial for keeping costs under control. Since different port authorities manage the major ports of the Canary Islands, they could be tempted to compete for transshipment cargoes, instead of working together to facilitate supply chain integration that would increase their competitive standing. The aim of the paper is twofold. First, the infrastructure and superstructure endowment of the main Canarian ports and their accessibility, by evaluating site and situation factors, is documented. Secondly, the connectivity of the main Canarian ports is assessed by means of graph theory. This provides important measures that define a port's competitiveness, and its potential to achieve or keep regional or global hub status, and also to follow its evolution. A brief review of papers measuring port connectivity based on graph theory is included to illustrate the current approaches in port network analysis, and to justify our methodological framework. A sub-network of 53 ports directly related with Las Palmas and Tenerife ports has been selected for this purpose. Our findings are mainly related to the connections among the nodes in the sample network, and to the position that the targeted ports hold. Additionally, some policy recommendations, regarding how to improve the connectivity and competitiveness of the Canarian ports, are also enumerated. Previous analysis indicates that, at present, the Las Palmas port is the only regional hub in the Canaries. Both Canarian port authorities should differentiate themselves by specializing in certain valued added services and increasing traffic in these services. This would avoid the danger of a destructive competition between them to attract transit traffic. In summary they should be proactive in maintaining and improving the main Canarian ports' connectivity. [ABSTRACT FROM AUTHOR]

Abstract: The literature review shows a wide range of methodologies aiming at determining the photovoltaic (PV) potential. Very often, the methodology scale is too large (continents, countries or large regions) or too small (cities) or it is based on specific and non-commonly available software tools. This is why the proposed methodology to determine the PV roof potential in regions and/or islands can be useful. This methodology has been applied to the Canary Islands. Firstly, the available roof area for PV systems is determined, based on the total roof surface (using real data from the Spanish Cadastre) and utilization factors according to the municipality type. The methodology proposed to calculate the available roof surface is then compared to other well-known methods, including potential improvements using Geographical Information Systems. Secondly, the mean annual global solar radiation per municipality on inclined surfaces has been determined. To do so, a review of different methodologies has been assessed in a comprehensible manner, seeking for the ones that provide accuracy and simplicity. Thirdly, the yearly PV production per municipality has been calculated. For this, a step-by-step method to calculate the PV system efficiency, based on existing literature, has been detailed. Three different scenarios depending on the shared use of the available roof surface are defined and the corresponding PV production is calculated. A sensitivity analysis is also included, analyzing PV production in two cases: depending on back ventilation of the roof-mounted PV systems and on PV cell type (poly-crystalline to mono-crystalline). Finally, an economic assessment based on cost-resource curves is carried out. The spirit of the paper is to develop a methodology based on accuracy and, at the same, simplicity, understanding such as a method where all the calculations can be easily done using pen and paper, calculator and common office software programs. [Copyright &y& Elsevier]

This paper deals with the design and configuration of a thermal solar installation adapted to a hotel complex in the south of the island of Gran Canaria (Canary Islands, Spain). The solar collectors are concentration cylinder parabolic of small dimension. The design and calculations are principally performed in order to study the viability of the thermal solar technology of concentration opposite to other technologies of existing renewable energies such as solar thermal plane collectors or solar photovoltaic. Based on the total energy demand and the available solar power capacity (limited by the available surface), the study of the implementation and integration of the installation with previous hotel energy facilities is carried out. The energy production amounts to 45.08 MWh/year in a surface of 40 m2. The study of its economic feasibility has also been performed. This project has been the first small scale cylinder parabolic solar collector installation proposed in the Canary Islands. This way, the use of thermal solar concentration technology is promoted in this area, leading to a major sensibility with the use of affordable, clean, and renewable energies. • Design and configuration of an small scale cylinder parabolic thermal solar installation. • The energy generated by just one PTC represents 42% of the present solar FPC. • The annual capacity of the SCT is 3.5 times higher than the capacity of the FPC. • An installed thermal power of 22 KW costs 2.5 €/W. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes the use of a new Measure–Correlate–Predict (MCP) method to estimate the long-term wind speed characteristics at a potential wind energy conversion site. The proposed method uses the probability density function of the wind speed at a candidate site conditioned to the wind speed at a reference site. Contingency-type bivariate distributions with specified marginal distributions are used for this purpose. The proposed model was applied in this paper to wind speeds recorded at six weather stations located in the Canary Islands (Spain). The conclusion reached is that the method presented in this paper, in the majority of cases, provides better results than those obtained with other MCP methods used for purposes of comparison. The metrics employed in the analysis were the coefficient of determination (R 2) and the root relative squared error (RRSE). The characteristics that were analysed were the capacity of the model to estimate the long-term wind speed probability distribution function, the long-term wind power density probability distribution function and the long-term wind turbine power output probability distribution function at the candidate site. [Copyright &y& Elsevier]

Abstract: This paper analyzes the influence of the tourist’s perception of overcrowding on a destination’s appeal. To do so, the use of the population density estimates is suggested to measure degrees of overcrowding in a tourist area, which in this paper is undertaken using panel data analysis. A tourist demand model is estimated in the study case, which consists of a number of resorts located in five islands of the same archipelago, Canary Islands. This distinctive case of close but different destinations makes it possible to isolate variations in demand due to changes in population density and other supply-side factors from other demand-oriented ones. Annual tourists coming from two different European countries to the islands were considered as endogenous variables. The empirical findings provide an indicator of each island’s maximum capacity and test some policy measures laid down to extend these limits. The estimation of the effect of population density on demand can serve as a useful tool for planning the future development in destinations where tourist attraction is mainly based on the natural values of the site. [ABSTRACT FROM AUTHOR]

Abstract: Due to the interannual variability of wind speed a feasibility analysis for the installation of a Wind Energy Conversion System at a particular site requires estimation of the long-term mean wind turbine energy output. A method is proposed in this paper which, based on probabilistic Bayesian networks (BNs), enables estimation of the long-term mean wind speed histogram for a site where few measurements of the wind resource are available. For this purpose, the proposed method allows the use of multiple reference stations with a long history of wind speed and wind direction measurements. That is to say, the model that is proposed in this paper is able to involve and make use of regional information about the wind resource. With the estimated long-term wind speed histogram and the power curve of a wind turbine it is possible to use the method of bins to determine the long-term mean energy output for that wind turbine. The intelligent system employed, the knowledgebase of which is a joint probability function of all the model variables, uses efficient calculation techniques for conditional probabilities to perform the reasoning. This enables automatic model learning and inference to be performed efficiently based on the available evidence. The proposed model is applied in this paper to wind speeds and wind directions recorded at four weather stations located in the Canary Islands (Spain). Ten years of mean hourly wind speed and direction data are available for these stations. One of the conclusions reached is that the BN with three reference stations gave fewer errors between the real and estimated long-term mean wind turbine energy output than when using two measure–correlate–predict algorithms which were evaluated and which use a linear regression between the candidate station and one reference station. [ABSTRACT FROM AUTHOR]

This paper integrates sedimentary, tectonic and volcanic geological processes inside a model of volcano-tectonic activity in oceanic intraplate domains related to rifted continental margins. The study case, the eastern Canary Basin (NE Atlantic), is one of the few places in the world where giant MDTs and Quaternary volcanic and hydrothermal edifices take place in intraplate domains. In this paper, we analyse how two structural systems (WNW-ESE and NNE-SSW) matching with the oceanic fabric control the location of volcanic systems, seafloor tectonic reliefs and subsequently the distribution of main sedimentary systems. Linear turbidite channels, debris flow lobes and the lateral continuity of structural and volcanic reliefs follow a WNW-ESE trend matching the tracks of the oceanic fracture zones. Furthermore, escarpments, anticline axes and volcanic ridges follow a NNE-SSW trend matching normal faults delimiting blocks of oceanic basement. The morpho-structural analysis of all the above geomorphological features shows evidence of a volcanic and tectonic activity from the middle–upper Miocene to the Lower–Middle Pleistocene spread over the whole of the eastern Canary Basin that reached the western Canary Islands. This reactivation changes the paradigm in the seamount province of Canary Islands reported inactive since Cretaceous. A tecto-sedimentary model is proposed for this period of time that can be applied in other intraplate domains of the world. A tectonic uplift in the study area with a thermal anomaly triggered volcanic and hydrothermal activity and the subsequent flank collapse and emplacement of mass transport deposits on the Western Canary Slope. Furthermore, this uplift reactivated the normal basement faults, both trending WNW-ESE and NNE-SSW, generating folds and faults that control the location of turbidite channels, escarpments, mass transport deposits and volcanic edifices. • Tecto-sedimentary model for intraplate oceanic settings: eastern Canary Basin. • Quaternary tectonics controls the sedimentary dynamic in the eastern Canary Basin. • Volcanic and tectonic reactivation since the Miocene until Quaternary. • Turbidite channels, MTD and volcanic cones are controlled by oceanic fracture zones. • Structural reliefs are controlled by deep faults delimiting oceanic basement blocks. [ABSTRACT FROM AUTHOR]

Abstract: Principal and subsidiary building structure characteristics and their distribution have been inventoried in Icod, Tenerife (Canary Islands) and used to evaluate the vulnerability of individual buildings to three volcanic hazards: tephra fallout, volcanogenic earthquakes and pyroclastic flows. The procedures described in this paper represent a methodological framework for a comprehensive survey of all the buildings at risk in the area around the Teide volcano in Tenerife. Such a methodology would need to be implemented for the completion of a comprehensive risk assessment for the populations under threat of explosive eruptions in this area. The information presented in the paper is a sample of the necessary data required for the impact estimation and risk assessment exercises that would need to be carried out by emergency managers, local authorities and those responsible for recovery and repair in the event of a volcanic eruption. The data shows there are micro variations in building stock characteristics that would influence the likely impact of an eruption in the area. As an example of the use of this methodology for vulnerability assessment, we have applied a deterministic simulation model of a volcanic eruption from Teide volcano and its associated ash fallout which, when combined with the vulnerability data collected, allows us to obtain the vulnerability map of the studied area. This map is obtained by performing spatial analysis with a Geographical Information System (GIS). This vulnerability analysis is included in the framework of an automatic information system specifically developed for hazard assessment and risk management on Tenerife, but which can be also applied to other volcanic areas. The work presented is part of the EU-funded EXPLORIS project (Explosive Eruption Risk and Decision Support for EU Populations Threatened by Volcanoes, EVR1-2001-00047). [Copyright &y& Elsevier]

Abstract: A very flexible joint probability density function of wind speed and direction is presented in this paper for use in wind energy analysis. A method that enables angular–linear distributions to be obtained with specified marginal distributions has been used for this purpose. For the marginal distribution of wind speed we use a singly truncated from below Normal–Weibull mixture distribution. The marginal distribution of wind direction comprises a finite mixture of von Mises distributions. The proposed model is applied in this paper to wind direction and wind speed hourly data recorded at several weather stations located in the Canary Islands (Spain). The suitability of the distributions is judged from the coefficient of determination R 2. The conclusions reached are that the joint distribution proposed in this paper: (a) can represent unimodal, bimodal and bitangential wind speed frequency distributions, (b) takes into account the frequency of null winds, (c) represents the wind direction regimes in zones with several modes or prevailing wind directions, (d) takes into account the correlation between wind speeds and its directions. It can therefore be used in several tasks involved in the evaluation process of the wind resources available at a potential site. We also conclude that, in the case of the Canary Islands, the proposed model provides better fits in all the cases analysed than those obtained with the models used in the specialised literature on wind energy. [Copyright &y& Elsevier]

Abstract: A finite mixture model of continuous variable probability is used in this paper to represent the distribution of directional wind speed. The model is comprised of a finite mixture of von Mises (vM-pdf) distributions. The parameters of the model are estimated using the least squares method. The range of integration to compute the mean angle and the standard deviation of wind direction is adjusted to minimum variance requirements. The suitability of the distributions is judged from the coefficient of determination R 2. The model is applied in this paper to wind direction data recorded at several weather stations located in the Canary Islands (Spain). The conclusion reached is that the mixture distribution used in this paper provides a very flexible model for wind direction studies and can be applied in a widespread manner to represent the wind direction regimes in zones with several modes or prevailing wind directions. In the case of the Canary Islands, mixtures of two vM-pdfs provide better fits in all the cases analysed than those obtained with the models proposed in the specialised literature on wind energy. The conclusion is also drawn that when the number of components N of the mixture distribution increases, the value of R 2 increases. However, the variations in R 2 are not significant for values of N greater than six. [Copyright &y& Elsevier]

For a century, the discovery of ferromanganese (Fe–Mn) nodules in the World Ocean was universally and indisputably credited to the Challenger circum-global oceanographic expedition of 1872–1876, during which the first manganese nodules and crusts were dredged up from the sea floor in February–March 1873. A century later, a counterclaim appeared in the literature, crediting Nordenskiöld's expedition on Sofia in 1868, five years before the Challenger findings, for the discovery of Fe–Mn nodules in the ocean. This counterclaim, widely accepted without scrutiny, was based on the Gustaf Lindström (1884) chemical analysis of a single bottom sediment sample among 14 samples from two Arctic expeditions led by Nordenskiöld: Sofia 1868 and Vega 1878–1880. The Lindström (1884) report published as an eight-page brochure in Swedish remained almost unknown to the research community until now. A close examination of this report and other historical evidence revealed that the counterclaim of discovery by the Sofia 1868 expedition to the Kara Sea is invalid based on three notable facts: (1) Sofia never sailed in the Kara Sea; (2) the single bottom sediment sample with an extremely high content of Mn (24%), was collected in the Kara Sea during the Vega Expedition across the Northeast Passage; (3) the Vega sampling was in 1878, not in 1868. Meanwhile, five and a half years prior to the Vega sampling, the first Fe–Mn nodules and crusts were dredged up from the sea floor on 18 February and March 7, 1873 during the Challenger expedition. These findings have been promptly reported and published in May 1873. Thus, the credit for the discovery of ferromanganese nodules in the World Ocean firmly belongs to the Challenger expedition. • The discovery of ferromanganese nodules in the World Ocean is revisited. • The Lindström (1884) paper with chemical analyses of sediment samples from Nordeskiöld's expeditions is examined. • The discovery of ferromanganese nodules in the World Oceanduring the Challenger 1872–1876 expedition is confirmed. [ABSTRACT FROM AUTHOR]

Geodiversity can be defined as the spatial variability of geo-elements. Its emergence as a research field is relatively recent, with a wide range of approaches and methods of evaluation and quantification already in use. The work described in this paper was carried out from a novel perspective. Firstly, the emphasis is specifically centred on geomorphological diversity. Secondly, mathematical ecology calculations are applied which tackle the problem on the basis of a larger number of diversity parameters. In addition, whereas most authors have focussed on mountainous and/or continental areas, for the first time a study of this type is applied to coastal landscapes. The analysis covers the full 459 km of volcanic coastline of the islands of Gran Canaria and La Palma (Canary Islands). These two oceanic islands were chosen for purposes of diversity comparison given their differing stages of geomorphic development. In accordance with an ad hoc geomorphological taxonomy, as developed in this study, 14 geomorphic groups and 42 subgroups were identified and quantified according to their presence [1] or absence [0] along the coastline. A cartographic-analytical method (coastline data-storing or CDS), based on the computation of binary information in the cartographic vector of the coastline, enabled calculation of the occurrence probability of these groups and subgroups. Both at local level (analyses of coastal morphoassemblages ) and general level, three components of geomorphological diversity (richness, evenness and dissimilarity) were estimated, through indices of richness (R), Shannon's entropy (H′) and Rao's quadratic entropy (Q). The data reveal that geomorphological coastal diversity is between 11.1% and 48.2% higher in Gran Canaria than in La Palma. The method was subjected to a fractal stress test through iterative mapping procedures to assess the effect of scale on the behaviour of the relative frequencies and indices. The variability that was obtained allowed the extraction of corrected values in the indices for La Palma (H′ c  = 1.88 ± 0.008 and Q c  = 0.183 ± 0.004) and Gran Canaria (H′ c  = 2.11 ± 0.019 and Q c  = 0.232 ± 0.003). A moving-window test was also applied as a rarefaction method to confirm the contrast in diversity in coasts of different size. The results enabled to advance hypotheses about the relation between coastal geomorphic diversity and geological age of islands. [ABSTRACT FROM AUTHOR]

The analysis presented in this paper is innovative, due to the lack of studies analysing how airlines compete in managing demand for domestic passenger air transport from mainland Spain to the Canary Islands. This research examines five Canary Island airports on 52 routes in order to explain the determinants of tourist air travel in this market. The regression analysis used the 2-stage least squares structural equation approach' with the implementation of instrumental variables in three equations: i) demand, ii) market share, and iii) price on each route. The results show that tourism in the Canary Island is very sensitive to income of the generating regions and prices of airline tickets. [ABSTRACT FROM AUTHOR]

Because of their geographical isolation, many areas depend mainly on imported fossil fuels for their water and energy production. In this context, the Canary Islands are one such remote area. Due to the topography of the islands, there are numerous isolated areas on each of the islands far from the major population centres. These are known as ‘islands within islands’. The main aim of this paper is to determine the feasibility or otherwise of supplying from renewable energy sources both the energy and water needs of the 219 inhabitants of El Risco located in the municipality of Agaete on the island of Gran Canaria (Spain). For this purpose, the potential use of existing renewable resources in this isolated area has been analysed, using hydrogen as energy vector. A reverse osmosis (RO) plant is integrated into the system to ensure water self-sufficiency and, in turn, constitutes a double storage system (hydrogen-water). Based on the results obtained from the study, the technical feasibility of the system is confirmed, with an annual energy production of 1,743,031 kWh/year compared to a consumption of 672,314.32 kWh/year, as well as a potable water production volume of 46,546.80 m 3 /year obtained from the RO plant. The reliability of the system is confirmed in the economic analysis, obtaining a renewable electricity cost of 0.107 €/kWh compared to 0.18 €/kWh when using conventional electricity. [ABSTRACT FROM AUTHOR]

In this paper the Canary archipelago is used as a study case to analyse and improve the municipal solid waste (MSW) planning process. The research has been conducted in four steps, namely, the Delphi technique helped to capture the knowledge of the local experts, the fuzzy TOPSIS to rank the MSW treatment methods more consistently, the System Dynamics to design a mathematical model based on MSW official historical data from 1999 up to 2014, and Scenario Analysis to forecast the future evolution of the MSW until 2030 under different policies. According to the results obtained by simulating several possible and desirable scenarios, the model predicts that by maintaining the current policies (Business As Usual scenario), it will be impossible to meet the targets of the MSW European Directive. The model also estimates the annual ratios to be reached for each component of the MSW so that they can comply with the European Directive, e.g. regarding to recycling (Scenario 2) and organic and rest fraction collection (Scenario 3) and the influences of the resident population and the equivalent touristic population on the total MSW generation until 2030. This methodological approach could be replicated in other territories. [ABSTRACT FROM AUTHOR]

Beaches exposed to continuous arrivals of tourists, such as on the Canary Islands, are subject to demands for quality requirements that are more stringent than in other coastal areas with seasonal tourism. It is therefore especially necessary to evaluate the recreational quality of these beaches. This paper develops a system of indicators (accessibility, environmental quality, water quality, comfort, scenic quality, human activity and infrastructure, facilities and safety) which integrates the narratives of stakeholders, and reveals high recreational quality values at urban and semi-urban beaches, moderate to high values at semi-urban beaches, and low values for services at natural beaches. In order to increase the quality of (i) accessibility at urban and semi-urban beaches, (ii) comfort, scenic quality, facilities and safety services at semi-urban beaches and (iii) water quality, facilities and safety at natural beaches, local management practices need to be adapted in accordance with the different types of beaches. [ABSTRACT FROM AUTHOR]

In the early 2000s, the Canary Islands emerged as the main gateway for unwanted sea migrants from Senegal into Spain. In this paper, I draw from a year of multi-sited ethnographic work to discuss the relationship between state actions to secure the border against these migrants, on the one hand; and smugglers and migrants' efforts to subvert those actions, on the other. My argument is that the relationship between the two is mutually constitutive: anti-immigration policy is a reaction to the actions of unwanted migrants, and unwanted migrants adapt to state efforts to seal the border against unwanted migration by finding and exploiting spaces of opportunity in the border. In the context of sea migration from Senegal to the Canary Islands, 2005 marks a major shift in this relationship. That year the European Union adopted a new framework for migration control (the Global Approach to Migration and Mobility), Frontex became operational, and Spain and Senegal deepened their cooperation to stop unwanted Europe-bound sea migration. This forced unwanted migrants to find creative ways to enter EU territory. I argue that combining the institutional and migrant perspectives allows us to explore the decentering of the state in the contemporary anti-immigration border regime, the emerging spatialities of the contemporary border, and understand the migrant's journey. This perspective also illuminates the messiness, violence, and multiplicity of interests involved in the bordering of Europe. [ABSTRACT FROM AUTHOR]

A global understanding of landscape dynamics, through local case studies, is a prime topic in land change science. Consequently, this approach should be urgently applied to changing and heavily transformed environments, such as coastal areas. The aim of this work is to study landscape changes, comparatively, by focusing on three coastal sedimentary landscapes in the Canary Islands (Spain). We examine changes in main land cover types and identify their driving forces, actors and institutions, analyze their inter-relationships, and match each case to a case-specific development model. The three landscapes reveal very different change processes with regard to population density, land cover, and major land change processes (i.e., resource extraction, urbanization, tourism, and nature protection). We found that socioeconomic, political, and natural/spatial driving force types are of highest importance, while the local level is dominant in all three cases. The findings of this study can be used to interpret other similar landscapes worldwide. Driving-force and organizational-level patterns may be expressed in a synthesized manner as we demonstrate in this paper. [ABSTRACT FROM AUTHOR]

This paper describes the impact of mineral content on wines and assesses the potential health risk from consuming these wines from Canary Islands. The metal content (B, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Zn) of red wines belonging to different regions in the Canary Islands was determined by ICP-OES. The studied wine regions were Valle de la Orotava, Tacoronte-Acentejo, Ycoden-Daute-Isora, Abona and Valle de Güimar in Tenerife Island and only one in La Gomera and La Palma Islands. According to the content found, elements could be classified in two categories: the main group including Ca, K, Mg, Na, and the ‘‘minor’’ set consisting of B, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb and Zn. Once calculated the metal intake through red wines consumption, we can conclude that Canarian drinkers are not exposed to unsafe levels of the metals studied, actually, the safety intake limits (daily) ranges between 0.9% in Zn and 2% in Cu, for normal drinkers. And also it has been demonstrated the good quality of Canarian red wines and there is no reason for health concern through the THQ calculation being the highest values determined in La Gomera wines. [ABSTRACT FROM AUTHOR]

This paper presents a cost-benefit analysis for the bi-directional functionality of plug-in electric vehicle charging, often called vehicle-to-grid. Plug-in electric vehicles represent an opportunity to reduce emissions from transportation, improve the efficiency, and also, it is a solution for storing electricity from the grid. The research is focused on the vehicle-to-home application for plug-in electric vehicles, which entails a bi-directional energy flowing from vehicles to households. The benefits from this use of the plug-in electric vehicles batteries are peak-shaving as well as valley-filling on the load curve, resulting in cost reductions for the user and the electric power system. In the case of islands, the use of this storage would allow an increased penetration of renewable energy sources and a reduction of costs. The research discusses the impact of vehicle-to-grid for the Canary Islands, where a plug-in electric vehicles penetration charging higher than a 20% would cause changes to the current demand curve peaks. The results show the benefits to both the system operator and the users, which may reduce mobility energy costs by a 50% through the time of usage. Vehicle-to-home regulation based on standards is recommended for incentivizing its functionality, the time of usage pricing, based on market prices, being the most beneficial for the user and the electric power system as a whole. [ABSTRACT FROM AUTHOR]

This paper investigates the use of renewable energies to supply hotels in island regions. The aim is to evaluate the effect of weather and occupancy fluctuations on the sensitivity of investment criteria. The sensitivity of the chosen energy system is examined using a Monte Carlo simulation considering stochastic weather data, occupancy rates and energy needs. For this purpose, algorithms based on measured data are developed and applied to a case study on the Canary Islands. The results underline that electricity use in hotels is by far the largest contributor to their overall energy cost. For the invested hotel on the Canary Islands, the optimal share of renewable electricity generation is found to be 63%, split into 67% photovoltaic and 33% wind power. Furthermore, a battery is used to balance the differences between day and night. It is found, that the results are sensitive to weather fluctuations as well as economic parameters to about the same degree. The results underline the risk caused by using reference time series for designing energy systems. The Monte Carlo method helps to define the mean of the annuity more precisely and to rate the risk of fluctuating weather and occupancy better. [ABSTRACT FROM AUTHOR]

This paper builds on recent corporate social responsibility (CSR) literature and on stakeholder theory. Our aim is to analyze the direct and indirect effects of employee-oriented CSR on hotel workers' quality of life (QoL). Based on survey collected from a sample of hotel employees in the Canary Islands (Spain), relationships were empirically examined through partial least square structural equation modeling (PLS-SEM). This study confirms that workers' perceptions of employee-oriented CSR positively and directly enhance their QoL. We found indirect positive effects through several mediators. Our results highlight the key role of working conditions, task significance, turnover intentions, and intrinsic quality on the relationship between employee-oriented CSR and QoL. Moreover, hotel service quality level is an antecedent of employee-oriented CSR. These findings advance the literature on CSR and reveal important managerial implications, especially in a post-pandemic scenario in which workers' overall QoL is essential to ensure no one is left behind. • Tourism, decent work, and quality of life are at the heart of 2030 Agenda for Sustainable Development • Workers' perceptions of employee-oriented CSR positively and directly affect workers' QoL • Working conditions, task significance, turnover intentions, and intrinsic work quality mediate between CSR and workers' QoL • Hotels' service quality level positively influences workers' perceptions of employee-oriented CSR [ABSTRACT FROM AUTHOR]

The aim of this paper is to describe and compare seasonal effects in daily air passenger arrivals. Multiple seasonal cycles of different lengths are usually observed in daily time series. To model weekly cycles over a short and fixed seasonal period, conventional formulations can be applied. However, the length of yearly and, above all, monthly seasonal cycles is not fixed. Yet, whatever the lengths of the seasonal periods, seasonal cycles can be modelled by using evolving spline functions in such a way that a seasonal effect at a proportion of the seasonal period is defined as a non-fixed parametric formulation of this proportion. Thus, restricted evolving spline models are useful to model this type of seasonal variation. The areas under the splines can measure changes in the magnitude of seasonal variations over time and can be used to compare the relevance of seasonal variations for different seasonal periods or different time series. This proposal is illustrated by applying it to daily series of air passengers arriving in the Canary Islands and at the rest of Spain's airports. • Complex seasonal patterns are described for daily series of air passenger arrivals. • Monthly seasonal cycles are modelled with non-fixed lengths of seasonal periods. • Restricted evolving spline models are applied to capture changing seasonal cycles. • The relative magnitude of weekly, monthly and yearly seasonal cycles is assessed. • Dissimilarity and complementarity between different seasonal cycles is measured. [ABSTRACT FROM AUTHOR]

The production of services in the accommodation sharing industry is heterogeneous in the sense that listings with different strategic management could adopt distinct technologies. This paper analyses the time-varying efficiency of the peer-to-peer accommodation sector using the input distance stochastic frontier model with random coefficients to accommodate both multi-input and multi-output technology and the technological heterogeneity among listings. An empirical analysis is conducted based on data from Airbnb and HomeAway listings in the Canary Islands (Spain), before, during and after the COVID-19 lockdown (source: AirDNA), in the period January 2019-September 2020 (monthly data). The results show technological heterogeneity between listings and time-varying inefficiency which negatively depends on productivity. Moreover, multi-unit hosts are clearly more efficient than single-unit hosts. A mean efficiency of around 78% during the study period was estimated. • The technological heterogeneity of the peer-to-peer accommodation is analysed. • The effect of the COVID-19 lockdown on the efficiency of listings is calculated. • A mean efficiency of 78% during the study period was estimated. • Multi-unit hosts are more efficient than single unit hosts. [ABSTRACT FROM AUTHOR]

As many other small islands and archipelagos, the Canary Islands depend to a high degree on energy imports. Despite its small surface, the archipelago has a high potential for renewable energy (RE) technologies. In this paper, we present a scenario pathway to a 100% RE supply in the Canary Islands by 2050. It relies on a back-casting approach linking the bottom-up accounting framework Mesap-PlaNet and the high resolution power system model REMix. Our analysis shows that locally available technology potentials are sufficient for a fully renewable supply of the islands’ power, heat, and land transport energy demands. To follow the pathway for achieving a carbon neutral supply, expansion of RE technology deployment needs to be accelerated in the short-term and efforts towards greater energy efficiency must be increased. According to our results, an extended linkage between energy sectors through electric vehicles as well as electric heating, and the usage of synthetic hydrogen can contribute notably to the integration of intermittent RE power generation. Furthermore, our results highlight the importance of power transmission in RE supply systems. Supply costs are found 15% lower in a scenario considering sea cable connections between all islands. [ABSTRACT FROM AUTHOR]

This paper discusses the combined use of tools from dynamical systems theory and remote sensing techniques and shows how they are effective instruments which may greatly contribute to the decision making protocols of the emergency services for the real-time management of oil spills. This work presents the successful interplay of these techniques for a recent situation, the sinking of the Oleg Naydenov fishing ship that took place in Spain, close to the Canary Islands, in April 2015. [ABSTRACT FROM AUTHOR]

Subtropical cyclones (STC) are low-pressure systems that share tropical and extratropical characteristics. Because of the great economic and social damage, the study of these systems has recently grown. This paper analyzes the cyclone formed in October 2014 near the Canary Islands and diagnoses such a cyclone in order to identify its correspondence to an STC category, examining its dynamical and thermal evolution. Diverse fields have been obtained from three different numerical models, and several diagnostic tools and cyclone phase space diagrams have been used. An extratropical cyclone, in its early stage, experimented a process of cut-off and isolation from the midlatitude flow. The incursion of a trough in conjunction with a low-level baroclinic zone favored the formation of the STC northwestern of the Canary Islands. Streamers of high potential vorticity linked to the cyclone favored strong winds and precipitation in the study domain. Cyclone phase space diagrams are used to complement the synoptic analysis and the satellite images of the cyclone to categorize such system. The diagrams reveal the transition from extratropical cyclone to STC remaining for several days with a subtropical structure with a quite broad action radius. The study of the mesoscale environment parameters showed an enhanced conditional instability through a deep troposphere layer. It is shown that moderate to strong vertical wind shear together with relatively warm sea surface temperature determine conditions enabling the development of long-lived convective structures. [ABSTRACT FROM AUTHOR]

Coastal areas have been under pressure throughout history. Today these environments are occupied by a large portion of the world population and are dramatically affected by human activities. For a better understanding of the natural evolution of coastal ecosystems and their present state, historical studies are necessary. For this purpose researchers should apply methods that combine different historical sources, such as historic mapping and oral sources. In this paper we examine land uses that led to the disappearance of an arid coastal dune system, and the way to study it. Results reveal that each different land use had a different impact on the environment, and this was in correspondence with socio-economic needs. Finally, we discuss the results obtained and the methodology used. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel cost – benefit model for bi-directional functionality of eVTOLs. • Optimization model using Genetic Algorithms is presented for archipelagos. • Canary Islands Case Study shows total net profit of eVTOL aircraft implementation. • The increase in renewable energy is 15% and emission reduction of around 4.6% • Profitable number of eVTOL aircraft per island is calculated. This research paper presents a novel approach for cost-benefit analysis for the bi-directional functionality of eVTOL (Electric Vertical Take-Off and Landing) aircraft charging. eVTOL aircrafts represents an emerging aviation market that seeks to revolutionize mobility, both intra-city and inter-city, through an air transportation system for passengers based on safety, efficiency and accessibility on demand. In this research, an optimization based on genetic algorithms has been used to find the number of eVTOL vehicles which makes vehicle-to-grid services profitable for each of the electrical systems considered. This research discusses the impact that vehicle-to-grid eVTOL aircraft would cause, changing the current demand curve peaks and the economic benefits for eVTOL end users, power plant companies and system operator. The results show that there is an increase in the penetration of renewable energy sources, causing a reduction of approximately 4.6% in global emissions. In addition, the benefits obtained by the stakeholders considered in the system is greater than zero. The methodology considered in this research offers a new perspective for electrical systems to predict the demand of eVTOL aircraft, in specific territories, such as in the presented case study in the Archipelago of Canary Islands. [ABSTRACT FROM AUTHOR]

Meeting decarbonization goals requires taking significant action on electricity systems, which are a major source of CO 2 emissions. Decarbonizing island electricity systems raises additional challenges due to their heavy historical dependence on fossil fuels and strict power-reserve and reliability requirements. To address this challenge, this paper presents a comprehensive optimization model for long-term capacity planning of island electricity systems. Our model determines an optimal mix of generation and transmission capacity to satisfy energy demand at least cost while respecting the strict technical constraints that are inherent in island systems. In addition, our model considers the use of thermal and renewable generation, electric vehicles providing electricity-system services, batteries, pumped-hydroelectric storage, and ac and high-voltage dc transmission lines. We demonstrate our model with a case study of the Canary Islands archipelago. Our results show that combining the aforementioned technologies reduces generation costs by up to 25% and capacity requirements up to 50% (relative to a case without the technologies). In addition, without any mechanism to internalize the social cost of carbon, fossil-fueled thermal generation is the lowest-cost source of energy. Environmental considerations demonstrate the benefits of renewable generation and result in these carbon-free energy sources supplying about 40% of the energy mix. [Display omitted] • Carbon pricing can increase renewable-energy supply up to 40%. • Energy storage reduce costs up to 23% and favors more renewable-energy capacity. • Transmission interconnectors reduce costs but do not increase renewable-energy use. • Combining technologies reduces costs by 25% and capacity requirements by 50%. • Strict reserve requirements may keep renewable-energy shares below 3%. [ABSTRACT FROM AUTHOR]

Several countries around the world have implemented policies to subsidize passengers who live on islands and travel domestically by air transport. This paper analyzes the effect of an exogenous change in the percentage of air transport resident subsidies in Spain on non-residents tourists' expenditure per day and overnight stays in corresponding regions. Drawing on monthly data from the period 2015–2019, a difference-in-difference estimator is applied, in addition to several robustness checks and placebo tests. We found a negative causal relationship between raising the subsidy percentage and non-residents tourists' expenditure per day on affected routes (routes between the mainland and islands). In fact, estimations show a reduction of between 9.6 and 12.2 per cent of non-residents tourists' expenditure per day on the Canary Islands. • Does a rise in the percentage of resident subsidies affect touristic expenditure and overnight stays? • A monthly sample of spanyards who travel within Spain (2015–2019) is used. • We use dif-in-dif estimator with OLS and QR, robustness checks and placebos tests. • Non-residents tourists' expenditure per day in Canary Islands drops due to subsidy change. [ABSTRACT FROM AUTHOR]

The estimation of clear-sky solar irradiance via clear-sky models depends on reliable values of aerosol optical depth, water vapor and ozone content. These atmospheric variables are rarely on-site measured and are generally provided as gridded estimates in very low spatial resolution (1°). The high spatial variability of atmospheric variables within the grid resolution (pixel) leads to important errors in those areas with great atmospheric variability, such as in mountainous regions. In this paper, the performance of three clear-sky solar irradiance models was evaluated in a site with especially great elevation range, the Izana station from the Baseline Surface Radiation Network (Tenerife, Canary Islands) located at a high elevation (2373 m) and just 14 km from the ocean. Aerosols data were obtained from measurements from the Aerosol Robotic Network (AERONET) at the same site. The evaluation was also compared with global horizontal irradiance estimations with clear-sky models in the Guimar station, located at a lower elevation (156 m) and only 11.5 km away from Izana. Results showed a strong influence of elevation on solar radiation estimation under clear-sky conditions. [ABSTRACT FROM AUTHOR]

The archipelago of the Canary Islands is one of the so-called ultra-peripheral territories of the European Union due to its geographical location away from the continent. Although the level of socioeconomic development and lifestyle of this region is comparable to that of any other of the European Union, it is just 100 km off the coast of Morocco, in the African continent. The population of the Canaries has been extensively studied with respect to their levels of POPs, and it has been described that their levels are relatively high compared to other European regions. It has been speculated with that the proximity to Africa may be associated with this level of contamination, but so far this theory has not been verified. This paper describes for the first time the levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in a sample of the population of Morocco (n = 131), which were compared with those of a similar sample of the population of permanent residents in the Canary Islands (n = 100) in order to check this hypothesis. Our results showed that Moroccans have higher median values of OCPs than the residents in the Canaries (∑ OCP = 150.2 ng/g lw vs. 83.4 ng/g lw, p = 0.0001). Regarding the PCBs, although recent studies have reported that new environmental sources of PCBs exist in several African countries (including Morocco), the plasma levels of most congeners were significantly higher in Canarians than in Moroccans, especially for the dioxin-like PCBs (median = 7.3 ng/g lw vs. 0.0 ng/g lw, p = 0.0001). The detailed analysis of our results suggests that the levels of these pollutants in the Canarian people are more influenced by their lifestyle and the previous use of these chemicals in the archipelago than by its geographical vicinity with Morocco. [ABSTRACT FROM AUTHOR]

This paper continues a line of research on improving strategic decisions (SD). The nature of governance issues (complex and uncertain world, lack of information, consideration of qualitative and quantitative information, participation of different actors in the decision making processes, etc.) implies that there is no unique solution or strategy in a complex system. On the contrary, there are a range of alternative strategies, which could lead to different futures (scenarios). Working with the qualitative methodology proposed allows decision makers and social actors to be more aware of the directions their decisions could lead the system; and what the key variables are for the implementation of public policies to achieve the desired (or agreed) scenario. An integrated methodology is discussed, and the process of desertification in the Canary Islands is used to illustrate it. [ABSTRACT FROM AUTHOR]