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Nationality is considered a highly relevant determinant of tourism expenditure. In this paper, we use survey data to estimate the main determinants of daily tourism expenditure in 2019 for five nationalities of a major coastal destination, the Canary Islands. A total of 38 regressors, based on literature, are used with the help of quantile regression analysis to understand the behaviour patterns of different expenditure segments. To obtain segmented information on the determinants of expenditure, independent quantile regression models for each nationality are estimated and compared. Results show that there are similarities but also some remarkable differences between nationalities regarding income, age, travel group, educational level, or content of the package that can be used in destination management and marketing. [ABSTRACT FROM AUTHOR]

Avocado production has boomed worldwide in recent years, and Spain, including the Canary Islands, has been no exception. The number of avocado growers in the region has increased significantly as growers recognize the potential of this crop. However, several species of spider mites (Tetranychidae) pose a risk to this crop, with the genus Oligonychus being the most diverse and having the greatest economic impact. In particular, Oligonychus perseae (Tuttle, Baker and Abbatiello) has been reported as the one mainly responsible for the economic damage in major avocado-producing regions worldwide. In this paper, we aim to present an overview of the studies conducted and the measures implemented to mitigate the impact of O. perseae after its arrival in the Canary Islands. Our objective is to provide a detailed description of the current status of this pest (O. perseae), with special attention to its situation 17 years after its first appearance in avocado crops in the Canary Islands. In doing so, we aim to provide valuable insights and knowledge to understand and manage better the challenges posed by O. perseae in this region. [ABSTRACT FROM AUTHOR]

In this paper, we introduce LagunAR, a mobile outdoor Augmented Reality (AR) application for providing heritage information and 3D visualization on a city scale. The LagunAR application was developed to provide historical information about the city of La Laguna in the XVI century, when it was the main city in the Canary Islands. The application provides a reconstructed 3D model of the city at that time that is shown on a mobile phone over-imposed on the actual city using geolocation. The geolocated position is used also for providing information of several points of interest in the city. The paper describes the design and implementation of the application and details the optimization techniques that have been used to manage the full information of the city using a mobile phone as a sensor and visualization tool. We explain the application usability study carried out using a heuristic test; in addition it is probed by users in a qualitative user test developed as preliminary research. Results show that it is possible to develop a real-time application that shows the user a city-scale 3D model and also manages the information of the points of interest. [ABSTRACT FROM AUTHOR]

Seagrass and seaweed meadows hold a very important role in coastal and marine ecosystems. However, anthropogenic impacts pose risks to these delicate habitats. This paper analyses the multitemporal impact of the construction of the largest industrial port in the Canary Islands, near the Special Area of Conservation Natura 2000, on Cymodocea nodosa seagrass meadows (sebadales) of the South of Tenerife, in the locality of Granadilla (Canary Islands, Spain). Very-high-resolution WorldView-2 multispectral satellite data were used for the analysis. Specifically, three images were selected before, during, and after the construction of the port (2011, 2014, and 2022, correspondingly). Initially, advanced pre-processing of the images was performed, and then seabed maps were obtained using the machine learning K-Nearest Neighbors (KNN) supervised classification model, discriminating 12 different bottom types in Case-2 complex waters. The maps achieved high-quality metrics with Precision values of 85%, 81%, and 80%, recall of 76%, 77%, and 77%, and F1 scores of 80%, 79%, and 77% for 2011, 2014, and 2022, respectively. The results mainly show that the construction directly affected the seagrass and seaweed habitats. In particular, the impact of the port on the meadows of Cymodocea nodosa, Caulerpa prolifera, and maërl was assessed. The total maërl population was reduced by 1.9 km2 throughout the study area. However, the Cymodocea nodosa population was maintained at the cost of colonizing maërl areas. Furthermore, the port sedimented a total of 0.98 km2 of seabed, especially Cymodocea nodosa and maërl. In addition, it was observed that Caulerpa prolifera was established as a meadow at the entrance of the port, replacing part of the Cymodocea nodosa and maërl areas. As additional results, bathymetric maps were generated from satellite imagery with the Sigmoid model, and the presence of a submarine outfall was, as well, presented. [ABSTRACT FROM AUTHOR]

Simple Summary: The ladybird beetle fauna of the Canary Islands is quite specific due to the presence of a number of species that do not occur anywhere else (the so-called endemic species). However, many ladybirds recorded in the archipelago are relatively recent arrivals from various parts of the world, as shown by our previous surveys carried out in several of the Canary Islands, including Fuerteventura, Lanzarote, Gran Canaria, and El Hierro. In this paper, we analyze the ladybird fauna of La Palma, one of the western islands of the archipelago, based on our field survey and already published data. The survey resulted in the recording of 26 species, seven of which had not previously been recorded on La Palma, and two of these seven had not been recorded on any of the Canary Islands. Combining our data and literature reports gives a figure of at least 35 ladybird species recorded to date on La Palma. This is fewer than on the central islands of the Canary archipelago (Gran Canaria and Tenerife), but more than on the other four islands (Fuerteventura, Lanzarote, La Gomera, and El Hierro). This study confirms previous observations that the Canary Islands are often colonized by exotic ladybird species. This paper provides new data on the ladybird beetles (Coccinellidae) of La Palma, one of the western islands of the Canarian archipelago. The field survey of 54 study sites resulted in recording 2494 ladybird individuals belonging to 26 species. Seven of the species recorded were new to La Palma, including two, Harmonia quadripunctata (Pontoppidan) and Nephus reunioni (Fürsch), which were not registered so far on any of the Canary Islands. Novius conicollis (Korschefsky) is synonymized with N. cruentatus (Mulsant). Taking our survey and literature reports into account, a total of at least 35 species of Coccinellidae have so far been recorded on La Palma. This richness in species is lower compared to that of the central islands of the Canarian archipelago, Gran Canaria (42 species) and Tenerife (41 species), but higher than that of the remaining four islands (between 22 and 27 species). The detection of two alien species new to La Palma, Nephaspis bicolor Gordon and Nephus reunioni (Fürsch), confirms earlier observations that colonization of the Canary Islands by ladybird species of exotic origins seems to be a frequent phenomenon. [ABSTRACT FROM AUTHOR]

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]

The chilli thrips Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) is an invasive polyphagous pest of several crops, and is native to South and East Asia. In recent decades, this thrips has successfully established in parts of the African and American continents. In the EPPO region its distribution is limited to Israel and Türkiye, and it is considered as under eradication in mainland Spain. This paper presents the first report of S. dorsalis on the island of Tenerife (Canary Islands, Spain), where individuals were initially found infesting mango in 2016, and subsequent inspections revealed infestations in 2022 that allowed its identification. [ABSTRACT FROM AUTHOR]

An intertidal sandstone reef, named barra de Las Canteras, protects the western coast of Las Palmas de Gran Canaria city (Canary Islands, Spain). The beach-reef system of Las Canteras constitutes one of the most valuable coastal geomorphological sites in the archipelago. Stratigraphic studies have identified the formation of the reef in the Last Interglacial (MIS 5e) in a coastal sedimentary paleo-environment. The rock structure is highly exposed to the Atlantic swell and consists mainly of a sandstone beachrock with a medium resistance to erosional processes. However, the historical and current erosion rates and the original extent of the reef are not known to date. This paper explores the geomorphological structure of the reef by combining a topo-bathymetric analysis (obtained by differential GPS, multibeam echosounder and hyperspectral sensor) and the analysis of geomorphological features on high-resolution images, obtained with a hyperspectral camera mounted on a UAV. The results provide a comprehensive, high-resolution image of the subaerial and submerged morphology of the reef. The structure reflects the distribution of erosional fronts and the existence of collapsing submarine blockfields and nearshore, uneroded, remnant reliefs. Detailed analysis of these features allows to estimate the probable original extent of the sandstone reef and to relate the erosional retreat processes to the sea-level dynamics during the Holocene. [ABSTRACT FROM AUTHOR]

This research analyses how the identity of the Europeans of the islands of Macaronesia (Azores, Madeira, Canary Islands and Cape Verde) was formed during the period of the Iberian Union with the aim of characterizing the traits of the island society. The fluid contacts between the islands and their oceanic environment strengthened among the islanders an attachment to the same island region made up of a population of extra-peninsular origin whose nexus was the Atlantic. This paper, which starts from the nesological approach to define the Macaronesian insular environment, supports the analysis in a broader geographic and methodological context: The Atlantic History. This study examines the principles of this discipline in relation to islands to apply its theoretical and conceptual framework to intrinsic territories in this ocean. [ABSTRACT FROM AUTHOR]

Despite their attractive appearance, the velvet spiders of the genus Eresus are an understudied group in some parts of their range. Such areas include the south-western Mediterranean. In this paper we present a description of a new species from Morocco and Algeria, Eresus elhennawyi sp. n. We named it after the Egyptian arachnologist Hisham El-Hennawy, who has worked on the arachnids of North Africa for several decades. This species lives under rocks in semi-desert habitats, so unlike most species of the genus Eresus, it does not burrow. Adult males seek out females in April. Their colouration is obviously a mimicry of co-occurring stinging mutilid wasps. The most morphologically similar species is Eresus crassitibialis Wunderlich, 1987 from the nearby Canary Islands. [ABSTRACT FROM AUTHOR]

A literature review regarding Gertrudis Segovia Álvarez shows this author has been forgotten from the critics despite being recognized as a successful writer at the beginning of the twentieth century. This paper aims archival research related to her stay in the Canary Islands and the influence of this time in her work. The findings show the issues Gertrudis Segovia embodied with her feminine identity because of an intellectual and emotional exclusion. Also, it is discovered in this paper the features of being a self-sacrificing woman, the importance of the influence of the masculine role in her life -her father and her husband, and the importance of her recognition by a female audience in the middle of the strong influence of the Catholicism in the social life and the private life as well. All of these features frame her initial recognition as an important author but also the forgetfulness of herself and her work. [ABSTRACT FROM AUTHOR]

Throughout the first decades of the 21st century, the maritime borders of the European Union have witnessed a growing and increasingly complex mobility of an irregular nature. Moreover, the effects of the COVID-19 crisis on many African countries revealed the weakness of the maritime border and its permeability, as well as its increased danger. This research aims to study these irregular migration flows by sea during 2020 and 2021, through the Atlantic border between the Canary Islands and Africa. The so-called "Canary route" is one of the most dangerous maritime routes in the world due to the ocean conditions, the distances that must be covered and the way in which migrants move. Our analysis will therefore focus on one of the central aspects of this crossing, its danger and associated accident rate, which can be measured in terms of the number of shipwrecks, deaths, and missing persons. The objectives of this paper are: i) to show the spatial location of those wrecks; ii) to give an estimate of data on missing persons and deaths; iii) to focus on the study of those persons affected; iv) to delve into the underlying causes; and v) to analyse the border control actions developed during the pandemic. With this aim, information has been compiled from different national and international sources: official records, contrasted data provided by some NGOs and the IOM, and testimonies of the agents involved. This material is used to reflect on the normalization of border control as a factor that inevitably leads to deaths and disappearances. It suggests that this event should be a central element in European migration policy, contributing to designing border control actions that go beyond containment, thereby preventing the loss of human lives. [ABSTRACT FROM AUTHOR]

Context. The Event Horizon Telescope (EHT) has recently published the first images of the supermassive black hole at the center of our Galaxy, Sagittarius A* (Sgr A*). Imaging Sgr A* is plagued by two major challenges: variability on short (approximately minutes) timescales and interstellar scattering along our line of sight. While the scattering is well studied, the source variability continues to push the limits of current imaging algorithms. In particular, movie reconstructions are hindered by the sparse and time-variable coverage of the array. Aims. In this paper, we study the impact of the planned Africa Millimetre Telescope (AMT, in Namibia) and Canary Islands telescope (CNI) additions to the time-dependent coverage and imaging fidelity of the EHT array. This African array addition to the EHT further increases the eastwest (u, v) coverage and provides a wider time window to perform high-fidelity movie reconstructions of Sgr A*. Methods. We generated synthetic observations of Sgr A*'s accretion flow and used dynamical imaging techniques to create movie reconstructions of the source. To test the fidelity of our results, we used one general-relativistic magneto-hydrodynamic model of the accretion flow and jet to represent the quiescent state and one semi-analytic model of an orbiting hotspot to represent the flaring state. Results. We found that the addition of the AMT alone offers a significant increase in the (u, v) coverage, leading to robust averaged images during the first hours of the observating track. Moreover, we show that the combination of two telescopes on the African continent, in Namibia and in the Canary Islands, produces a very sensitive array to reconstruct the variability of Sgr A* on horizon scales. Conclusions. We conclude that the African expansion to the EHT increases the fidelity of high-resolution movie reconstructions of Sgr A* to study gas dynamics near the event horizon. [ABSTRACT FROM AUTHOR]

Predicting brain aging can help in the early detection and prognosis of neurodegenerative diseases. Longitudinal cohorts of healthy subjects scanned through magnetic resonance imaging (MRI) have been essential to understand the structural brain changes due to aging. However, these cohorts suffer from missing data due to logistic issues in the recruitment of subjects. This paper proposes a methodology for filling up missing data in longitudinal cohorts with anatomically plausible images that capture the subject‐specific aging process. The proposed methodology is developed within the framework of diffeomorphic registration. First, two novel modules are introduced within Synthmorph, a fast, state‐of‐the‐art deep learning‐based diffeomorphic registration method, to simulate the aging process between the first and last available MRI scan for each subject in three‐dimensional (3D). The use of image registration also makes the generated images plausible by construction. Second, we used six image similarity measurements to rearrange the generated images to the specific age range. Finally, we estimated the age of every generated image by using the assumption of linear brain decay in healthy subjects. The methodology was evaluated on 2662 T1‐weighted MRI scans from 796 healthy participants from 3 different longitudinal cohorts: Alzheimer's Disease Neuroimaging Initiative, Open Access Series of Imaging Studies‐3, and Group of Neuropsychological Studies of the Canary Islands (GENIC). In total, we generated 7548 images to simulate the access of a scan per subject every 6 months in these cohorts. We evaluated the quality of the synthetic images using six quantitative measurements and a qualitative assessment by an experienced neuroradiologist with state‐of‐the‐art results. The assumption of linear brain decay was accurate in these cohorts (R2 ∈ [.924,.940]). The experimental results show that the proposed methodology can produce anatomically plausible aging predictions that can be used to enhance longitudinal datasets. Compared to deep learning‐based generative methods, diffeomorphic registration is more likely to preserve the anatomy of the different structures of the brain, which makes it more appropriate for its use in clinical applications. The proposed methodology is able to efficiently simulate anatomically plausible 3D MRI scans of brain aging of healthy subjects from two images scanned at two different time points. [ABSTRACT FROM AUTHOR]

On 2029 April 13, asteroid Apophis will pass within six times of the Earth's radius (∼31 000 km above the surface) in the closest approach of this asteroid in recorded history. This event provides unique scientific opportunities to study the asteroid, its orbit, and surface characteristics at an exceptionally close distance. In this paper, we perform a novel synthetic geometrical, geographical, and temporal analysis of the conditions under which the asteroid can be observed from the Earth with a particular emphasis on the conditions and scientific opportunities for bistatic radar observations, the most feasible radar technique applicable during such a close approach. For this purpose, we compile a list of present and future radio observatories or radio facilities around the globe, which could participate in bistatic radar observation campaigns during the close approach of Apophis. We estimate signal-to-noise ratios, apparent sky rotation, surface coverage, and other observing conditions. We find that a global collaboration of observatories across Australia, Africa, Europe, and America will produce high-resolution delay-Doppler radar images with signal-to-noise ratios above 108, while covering ∼85 per cent of the asteroid surface. Moreover, if properly coordinated, the extreme approach of the asteroid might allow for radio amateur detection of the signals sent by large radio observatories, and citizen science projects could then be organized. We also find that for visual observations, the Canary Islands will offer the best observing conditions during the closest approach, both for professionals as well as for amateurs. The apparent size of Apophis will be 2–3 times larger than typically seeing, allowing for resolved images of the surface. [ABSTRACT FROM AUTHOR]

The extraordinary expectations of construction of tourist accommodation at the end of the nineties in the destination of the Canary Islands (Spain) determined the convenience of intervening from the state. The purpose was to limit its unsustainable growth. The problem resulted in the way to address it, when different alternatives emerged from two groups of politicians and technicians. The main objective of this paper is to describe their behavior. This has allowed us to identify the public actors who were involved and led this pre-operational process, to discover their behavior patterns and leadership capacity, as well as the reactions of some to certain proposals and actions of others, especially when there were conflicts and divergences when multiple interests and technical and political points of view converged. For this, the content analysis approach or correlate of the moment has been chosen. [ABSTRACT FROM AUTHOR]

The Canary Island Long-Baseline Observatory (CILBO) is a double-station meteor camera setup located on the Canary Islands operated by ESA's Meteor Research Group since 2010. Observations of meteors are obtained in the visual wavelength band by intensified video cameras from both stations, supplemented by an intensified video camera mounted with a spectral grating at one of the locations. The cameras observe during cloudless and precipitation-free nights, and data are transferred to a main computer located at ESA/ESTEC once a day. The image frames that contain spectral information are calibrated, corrected, and finally processed into line intensity profiles. An ablation simulation, based on Bayesian statistics using a Markov chain Monte Carlo method, allows determining a parameter space, including the ablation temperatures, chemical elements, and their corresponding line intensities, to fit against the line intensity profiles of the observed meteor spectra. The algorithm is presented in this paper and one example is discussed. Several hundred spectra have been processed and made available through the Guest Archive Facility of the Planetary Science Archive of ESA. The data format and metadata are explained. [ABSTRACT FROM AUTHOR]

In the context of current climate change, it is a priority to develop mechanisms that facilitate the integration of the public's perspective in the fight against this phenomenon. Organisations such as the IPCC have highlighted the importance of paying attention, in the inexorable transition that is approaching, to the perception and experiences of the population as sources of information complementary to scientific evidence. In addition, it is of interest to check the assessment of institutional action in this respect and the degree of social awareness of this global challenge. Thus, this paper, based on an extensive survey carried out on the island of Tenerife (Canary Islands), analyses the resident population's perception of the causes and effects of climate change, as well as their environmental commitment and knowledge of governmental mitigation and adaptation initiatives. There is a high degree of concern about the issue among citizens, who support the existence of climate change, say they know what it consists of and generally have a negative view of the actions of public administrations, and are unaware of the initiatives that have been approved. [ABSTRACT FROM AUTHOR]

The study analyses the creation of the Juzgado de Indias and the problems that arise between the first Official of the new institution, Francisco de Vera, and the Cabildo of La Palma, despite the determination with which the local government defended the establishment of the institution on the island, because it was the monopolistic control of commercial traffic between Canary Islands and America. For this work, we use as primary sources the Acts of the Cabildo de La Palma between 1559 and 1599 and the royal papers included in the Archivo General de Indias. [ABSTRACT FROM AUTHOR]

Cetaceans are considered ecosystem engineers and useful bioindicators of the health of marine environments. The Eastern North Atlantic is an area of great geographical and oceanographic complexity that favours ecosystem richness and, consequently, cetacean occurrence. Although this occurrence has led to relevant scientific research on this taxon, information on the composition of this research has not been assessed.We aimed to describe and quantify the evolution of research on cetaceans in the Eastern North Atlantic, highlighting the main focal areas and trends.We considered 380 peer‐reviewed publications between 1900 and 2018. For each paper, we collected publication year, research topics and regions, and species studied. We assessed differences among regions with distinct socio‐economic landscapes, and between coastal and oceanic habitats. To evaluate the changes in scientific production over time, we fitted a General Additive Model to the time series of numbers of papers.Although research in this region has been increasing, the results show relatively little research output in North African and coastal regions within the study area. Moreover, except for four studies, research was restricted to a few miles around the coast of the main islands, leaving offshore regions less well surveyed. There was little research on genetics, acoustics, and behaviour. Most papers were focused on the Azores and Canary Islands, and mostly involved Tursiops truncatus, Delphinus delphis, and Physeter macrocephalus. Species considered Endangered or Near Threatened were the subjects of only 10% of the studies.We suggest a greater research focus on beaked whales (Ziphiidae) in Macaronesia, as well as collaborative efforts between research teams in the region, by sharing data sets, and aiming to produce long‐term research. Moreover, a Delphi method approach, based on questionnaires answered by experts, could be attempted to identify priority research for cetaceans in these areas. [ABSTRACT FROM AUTHOR]

In the eastern Atlantic Ocean, several volcanic archipelagos are located close to the margin of the African continent. This configuration has inspired previous studies to suggest an important role of edge-driven convection (EDC) in the generation of intraplate magmatism. In a companion paper (Manjón-Cabeza Córdoba and Ballmer, 2021), we showed that EDC alone is insufficient to sustain magmatism of the magnitude required to match the volume of these islands. However, we also found that EDC readily develops near a step of lithospheric thickness, such as the oceanic–continental transition ("edge") along the western African cratonic margin. In this work, we carry out 3D numerical models of mantle flow and melting to explore the possible interactions between EDC and mantle plumes. We find that the stem of a plume that rises close to a lithospheric edge is significantly deflected ocean-ward (i.e., away from the edge). The pancake of ponding hot material at the base of the lithosphere is also deflected by the EDC convection cell (either away or towards the edge). The amount of magmatism and plume deflection depends on the initial geometric configuration, i.e., the distance of the plume from the edge. Plume buoyancy flux and temperature also control the amount of magmatism, and influence the style and extent of plume–EDC interaction. Finally, comparison of model predictions with observations reveals that the Canary plume may be significantly affected and deflected by EDC, accounting for widespread and coeval volcanic activity. Our work shows that many of the peculiar characteristics of eastern Atlantic volcanism are compatible with mantle plume theory once the effects of EDC on plume flow are considered. [ABSTRACT FROM AUTHOR]

This paper explores the colonialities of trans/gender and the Canary Islands to interrogate the in/adequacy of critical theory as a tool applied to Global South issues. In both cases, critical theory is found to be lacking due to its compulsion to predetermine and essentialise relations, which undermines its capacity to engage with the multiplicitous im/possibilities of trans/gender and post/coloniality. In lieu of a critical approach, the authors each engage with relational ontologies that offer a more capacious relationship with their respective colonialities. In the case of trans/gender, agential realism offers Pasley a means to trace the entanglements, potentiating more response-able becomings. For Ramirez, te Ao Māori allows her to imagine a future reconfigured to account for the multiple tensions that co-constitute Canary Island relationships with colonisation. While trans/gender and the Canary Islands are perhaps not an obvious pairing, the im/possibilities offered by each are deeply entangled in colonisation and the ongoing reconfiguration of colonialities in the pursuit of more just worlds. [ABSTRACT FROM AUTHOR]

This paper analyses the profile of individuals who decide to purchase a Sport Utility Vehicle (SUV) in a medium-sized isolated island system such as Tenerife Island. To achieve this objective, we used a survey conducted in 2017 to identify the characteristics of the individuals most likely to choose an SUV or another type of vehicle or be undecided. Subsequently, a discrete choice model was estimated to assess the probability that an individual chooses one of the three options as a function of their socio-economic characteristics, mobility routines, vehicle attributes and psychosocial traits. The results show the need to adopt energy policy measures related to vehicle choice, as they put the fulfilment of the decarbonization objectives for the energy transition in the Canary Islands at risk. Firstly, the authorities should carry out campaigns to achieve a more environmentally conscious behaviour by highlighting the higher consumption and emission levels of this type of vehicle. Secondly, subsidies for more efficient new vehicles and taxation should promote the purchase of low-emission vehicles to compensate for the greater willingness to pay of SUV buyers. In particular, purchase taxation should be linked to emission levels rather than only considering power, engine characteristics or labelling. [ABSTRACT FROM AUTHOR]

This paper presents a tidal current meter that is based on the inertial acceleration principle for offshore infrastructures in deep water. Focusing on the marine installations of the aquaculture industry, we studied the forces of tides at a depth of 15 m by measuring the acceleration. In addition, we used a commercial MEMS triaxial accelerometer to record the acceleration values. A prototype of the tidal measurement unit was developed and tested at a real offshore aquaculture infrastructure in Gran Canaria, which is one of the Canary Islands in the Atlantic Ocean. The proposed tidal measurement unit was used as a recorder to assess the complexity of measuring the frequency of tidal currents in the short (10 min), medium (one day) and long term (one week). The acquired data were studied in detail, in both the time and frequency domains, to determine the frequency of the forces that were involved. Finally, the complexity of the frequency measurements from the captured data was analyzed in terms of sampling ratio and recording duration, from the point of view of using our proposed measurement unit as an ultra-low-power embedded system. The proposed device was tested for more than 180 days using a lithium-ion battery. This working period was three times greater than the best alternative in the literature because of the ultra-low-power design of the on-board embedded system. The measurement accuracy error was lower than 1% and the resolution was 0.01 cm/s for the 0.8 m/s velocity scale. This performance was similar to the best Doppler solution that was found in the literature. [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 Island Long-Baseline Observatory (CILBO) is a double station meteor camera setup located on the Canary Islands and operated by ESA's Meteor Research Group since 2010. Observations of meteors are obtained in the visual wavelength band by intensified video cameras from both stations, supplemented by an intensified video camera mounted with a spectral grating at one of the locations. The cameras observe during cloudless and precipitation-free nights and data are transferred to a main computer located at ESA/ESTEC once a day. The image frames that contain spectral information are calibrated, corrected, and finally processed into line intensity profiles. An ablation simulation, based on Bayesian statistics using a Markov-Chain Monte-Carlo method, allows to determine a parameter space, including the ablation temperatures, chemical elements and their corresponding line intensities, to fit against the line intensity profiles of the observed meteor spectra. The algorithm is presented in this paper and one example is discussed. Several hundred spectra have been processed and made available through the Guest Archive Facility of the Planetary Science Archive of ESA. The data format and meta-data are explained. [ABSTRACT FROM AUTHOR]

Occupational stress, as a negative facet, is a pervasive problem with significant implications for organizations, employees, welfare systems and health. The implementation of measurement tools that can capture the different organizational dimensions that determine stress in workers is part of the stress management and troubleshooting strategy that every company must manage daily. The aim of the present study was to adapt and validate the 25-item version of the ILO-WHO stress scale by Ivancevich and Matteson in the context of the Canary Islands of Spain. The tool assesses specific organizational dimensions of work-related stress determinants: organizational climate and structure, leader influence, cohesion, territory, technology and group support. An exploratory factor analysis (EFA) on a sample of 1510 Canary Islands workers was carried out. The results indicate that the job stress scale revealed adequate psychometric properties, construct validity and internal consistency (Cronbach's alpha = 0.972), and it can be profitably used to measure stress. At the end of the paper, theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

This paper examines the features and practices of military command during a war of conquest, as exhibited by Castilian captains at the dawn of Iberian Atlantic expansion between the Late Middle Ages and the Early Modern Age. Focusing on Castilian royal chronicles of military campaigns against the aboriginal people of the Canary Islands, such texts demonstrate continuities with the military discourse developed during the war against the Muslims in medieval Spain, as well as adaptation to a new geographical, social and cultural context, embodied in the experiences of the conquest of the Americas. [ABSTRACT FROM AUTHOR]

The location, size, and structure of the farmlands and hydraulic systems built by the Indigenous inhabitants of Gran Canaria, Canary Islands, Spain, remain unknown. This hampers our ability to understand how they organized agricultural production and how European settlers transformed local landscapes to build commercial plantations in the late fifteenth century. This paper combines an analysis of archival sources with the study of agricultural landscapes and practices to identify and describe the fields that were employed by the first colonists of Agüimes and Temisas, and to derive information about the location, design, and management of the pre-Hispanic farmlands. [ABSTRACT FROM AUTHOR]

Renewable energy has a key role to play in the transition towards a low‐carbon society. Despite its importance, relatively little attention has been focused on the crucial impact of weather and climate on energy demand and supply, or the generation or operational planning of renewable technologies. In particular, to improve the operation and longer‐term planning of renewables, it is essential to consider seasonal and subseasonal weather forecasting. Unfortunately, reports that focus on these issues are not common in scientific literature. This paper presents a systematic review of the seasonal forecasting of wind and wind power for the Iberian Peninsula and the Canary Islands, a region leading the world in the development of renewable energies (particularly wind) and thus an important illustration in global terms. To this end, we consider the scientific literature published over the last 13 years (2008–2021). An initial search of this literature produced 14,293 documents, but our review suggests that only around 0.2% are actually relevant to our purposes. The results show that the teleconnection patterns (North Atlantic Oscillation [NAO], East Atlantic [EA] and Scandinavian [SCAND]) and the stratosphere are important sources of predictability of winds in the Iberian Peninsula. We conclude that the existing literature in this crucial area is very limited, which points to the need for increased research efforts, that could lead to great returns. Moreover, the approach and methods developed here could be applied to other areas for which systematic reviews might be either useful or necessary. [ABSTRACT FROM AUTHOR]

Rockfalls are frequent and damaging phenomena that occur on steep or vertical slopes, in coastal areas, mountains and along coastal cliff. Water, in different forms, is the most common triggered factor of rockfalls. Consequently, we can consider that precipitation is the most influential factor for slope instabilities and it influences almost all other water parameters. Besides, the specific geology of the Anaga nature reserve in the volcanic island of Tenerife, together with its steep landscape, contributes to the instability of the slopes and frequent rockfalls. Recently, due to climate change and global warming, the annual precipitation/rainfall has declined but the number of heavy storms, associated with intense rainfall and strong winds, events that exceed precipitation thresholds in a brief period has increased which triggers slope movements. This paper describes the analysis of information on rainfall-induced rockfalls in Anaga, Tenerife (Canary Islands), to forecast rock failures of social significance and to improve the capability to respond and emergency decision making. To define reliable thresholds for a certain area, we analized information during the period 2010–2016, reconstructed the rockfall events, and statistically analyzed the historical rainfall conditions that led to landslides. The summary graph correlating precipitation to the probability of occurrence of an event was plotted. Statistical and probability graphs were made with the direct relationship between the number of rockfall events and total rainfall in that period by examining the maximum daily precipitation, not only on the day of the event but up to 3 days before. Hence, the results of this study would serve as a guide for the possible forecasting of rainfall-induced rockfalls, especially for road maintenance services, so that they can be on alert or mobilize the necessary resources in advance depending on the intensity of the expected rainfall. Highlights: We have determined the correlation between the probability of occurrence of a rockfall event in a natural reserve (Anaga, island of Tenerife, Canary Islands) and the expected rainfall intensity. We have observed the time delay between the occurrence of rainfall and rock falls, corroborated by experience in this area, between the day of the event and the day of the maximum rainfall associated with it. We have provided a tool to be used by the Civil Protection and Emergency and Road Maintenance and Conservation Services of the island of Tenerife as part of their management to mobilise the necessary resources or means or to adopt traffic limitations or restrictions depending on the level of alert decreed for adverse meteorological phenomena related to rainfall. [ABSTRACT FROM AUTHOR]

In this paper, we perform the first multidisciplinary study of perinatal burials at a pre‐Hispanic domestic site in Gran Canaria. For that, we carried out bioanthropological analyses, the genetic determination of the molecular sex of the individuals, and the contextualization of their chronological and cultural affiliations. To date, these remains had been associated to a local re‐interpretation of a Phoenician‐Punic tophet or as evidence of female infanticide within the mechanisms of demographic control of the ancient Canarians. However, these proposals did not take into account the recurrence of this type of human remains outside the normative cemeteries of the indigenous population or considered the demographic profile of coetaneous necropolises. In the light of the age of death and the molecular sex of the individuals, and the results obtained from the taphonomic and chronological analyses, we propose an alternative historical scenario, directly linked to high perinatal mortality rates and the development of specific burial practices for those individuals that died around the time of birth. [ABSTRACT FROM AUTHOR]

This paper aims to assess public preferences and WTP for policies addressing social inclusion. As a result of surveying 1250 residents in the Canary Islands (Spain) it has been found that society is highly sensitive to price, since people always choose to pay the cheapest option in support of social inclusion. In addition, the interviewees show a greater preference for basic income as a form of policy with a WTP of about 60 euros, while the WTP for other programmes related to awareness are less than 39 euros/year. The study allows to formulate a package of recommendations to increase the effectiveness of current policies aiming to promote a more inclusive and resilient society. [ABSTRACT FROM AUTHOR]

This paper presents the way of proceeding graphically, through architectural drawing, during the rationalist period in the Canary Islands. For this purpose, we have used a paradigmatic figure among the architects who developed their professional activity in the islands, his name is Miguel Martín Fernández de la Torre, who estudied architecture at the Madrid School of Architecture. The architectural proposals made in his professional development have been carried out in the different islands of the archipelago, we are going to concentrate on some works of his large graphic production, these exemplify his production; some of these works are registered in the Iberian DOCOMOMO. The drawing of rationalism in the Canary Islands, seen through the drawings of this architect, is framed within the coordinates of Spanish rationalism, which confirms that the communication networks between professionals functioned in a fairly fluid manner; likewise, the contribution of international information is also confirmed. [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]

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 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]

Implementation of the Global Sulphur Cap (GSC), in January 2020, boosted scrubber installation in vessels to fulfill the new air emission limitations. This increase in scrubbers' use has intensified concern about its environmental performance. Even though achievement of GSC requirements through this mitigation system has been widely proven, the impact of wash water discharge on the marine environment remains under discussion. In this paper, an assessment environmental model is introduced to quantify in monetary terms the performance of feeder vessels that operate with several mitigation systems. This model attempts to improve traditional air emission evaluations by including the impact of scrubbers' discharges on the marine environmental. In this way, the analysis not only allows different mitigations systems to be ranked by considering their capacity to reduce air emissions, but also provides further information about the marine eutrophication and ecotoxicity impact from scrubbers' discharge. Through the model's application to a regular shipping line between the Canary Islands and the Iberian Peninsula, it was found that, the scrubber, regardless of its operation mode (open- or closed loop), is the most efficient mitigation option after the Liquefied Natural Gas (LNG) fuel shift. The impact of scrubbers' discharge was not as significant as expected on the feeder vessel's total pollution since this provides similar relative weight to the methane emissions from a dual-engine option by operating with LNG. The results also show the need to more closely research the marine eutrophication impact of closed-loop scrubbers. Finally, this paper warns about a significant dispersion on the monetary values of marine ecotoxicity and eutrophication, due to a high dependence of the results on the frameworks' localization. Consequently, further research is needed on the homogenization of pollution monetization in the marine environment. • Assessment environmental model for mitigation systems on feeder vessels. • Join evaluation of air emissions, eutrophication and ecotoxicity of scrubbers. • Reduced environmental impact of scrubbers' discharges on total pollution of feeders. • High dispersion of monetary values for eutrophication and ecotoxicity on sea waters. • Further research is required about eutrophication impact of closed-loop scrubbers. [ABSTRACT FROM AUTHOR]

The reproductive aspects of all Plesionika species are relatively well known worldwide, except for the deepest species of the genus, Plesionika williamsi , for which little information is available throughout its range. The ovarian maturity, sex ratio, brood size, and size-depth distribution of the deep-sea shrimp Plesionika williamsi (Pandalidae) in the Canary Islands (eastern-central Atlantic) were analysed. Ovigerous females were observed all year round, with the highest number of ovigerous females recorded between July and October. The presence of a greater number of ovigerous females during the summer may reflect a high local availability of food or the optimal abiotic conditions, which are factors with a strong influence on reproduction. The presence of non-ovigerous mature females throughout the year indicates that their resting period in the reproductive cycle occurs asynchronously. The physiological size at first sexual maturity was 19.24 mm in carapace length (CL) and the length at first sexual maturity was estimated at 23.15 mm CL. Estimates of size at first sexual maturity based on ovigerous females describe the result of the reproduction process, whereas size at first sexual maturity based on ovarian maturity deals with physiological preparation for reproduction. The modal size class of egg production was 24–30 mm CL, which yielded 83.22% of the population egg production. Plesionika williamsi is an iteroparous species that can produce small eggs during egg extrusion. The mean number of external embryos carried by females was 3048 and can be considered a true approximation of the number of larvae released in each batch, which depend on the conditions existing in each system. The shallower individuals are associated with a depth stratum that represents the boundary between two water masses present in the Canary Islands. The increase in size with depth is related to the presence of submarine volcanic canyons, which constitutes a flow channel of surface organic matter to depth. • Ovigerous females during the summer days may reflect a high local availability of food or the optimal abiotic conditions. • The resting period in the reproductive cycle occurs asynchronously. • Plesionika williamsi is an iteroparous species that can produce small eggs during egg extrusion. • External embryos carried by females can be considered a true approximation of the number of larvae released. • The increase in size with depth is related to the presence of submarine volcanic canyons. [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]

[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]

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]

This paper proposed a pitching wave energy converter with adjustable natural period (called C-WEC), which is achieved by moving the movable mass block. A prototype was fabricated and tested in a wave flume to study the performance of the C-WEC. Free decay tests demonstrated that the natural period of the prototype can be adjusted between 1.60 s and 3.30 s. The wave flume tests showed that for regular and irregular waves, the prototype can capture high mechanical power and exhibit large response amplitude operator (RAO) as well as high capture width ratio (CWR) across a wide range of wave periods, avoiding poor performance in non-resonant states. The Froude scaling law was used to assess the annual average power of a 1:16th full-scale C-WEC in real seas off the Canary Islands based on the measured mechanical power in irregular waves. The result showed that the annual average power of the C-WEC using tuning control can be up to 29.8 kW, an increase of 67.4% compared to the WEC with a constant natural period. The experimental results showed that the C-WEC is a promising pitching wave energy converter and its natural period adjustment method can be easily applied to other pitching WECs. • A pitching WEC with adjustable natural period (called C-WEC) was proposed. • A C-WEC prototype was fabricated and tested in a wave flume. • Prototype's natural period can be adjusted between 1.6 s and 3.30 s. • Prototype can capture high mechanical power across a wide range of wave periods. • Froude scaling law was used to assess the full-scale C-WEC's annual average power. [ABSTRACT FROM AUTHOR]

There is a growing interest in the study of mesopelagic and bathypelagic species due to their implication in the active carbon flux and climate change. Underwater acoustics is one of the most efficient methods to study such widely distributed communities. However, there are several challenges among which the reduced spatial resolution with depth for vessel-mounted echosounders stands out. The increase in sampling volume with range precludes observation of fine structures within the scattering layers or the study of less-aggregated organisms far from the transducer face. Echosounders are thus increasingly being deployed in alternative platforms that get the transducer close to the layers of interest. We present here the comparison between two active acoustic platforms used to analyse mesopelagic and bathypelagic species: a vessel-mounted EK60 scientific echosounder and a 6000 m depth rated Acoustic Zooplankton Fish Profiler (AZFP) attached to a CTD rosette. Both systems depicted similar vertical distributions and scattering at 38 kHz for the main scattering layers recorded around the Canary Islands but the finer vertical resolution of the AZFP discerned a series of sub-layers within them that differed in scattering, avoidance and sparsity. The availability of high frequencies at depth also provided further insights on the frequency response of those layers. However, the horizontal orientation of the AZFP created sidelobe artefacts close to the surface and bottom that limit its use in those areas. Signal-to-noise ratio of the AZFP system in the bathypelagic zone also precludes applying echointegration analysis at those depths or outside the denser scattering layers. Finally, the visualization of horizontal or temporal patterns such as migration or mesoscale features is limited to a coarse resolution using data from closely spaced successive stations. New challenges encountered with vertically-deployed echosounders and recommendations for their use are pointed out. Although no scattering layers were detected in the bathypelagic zone, this study unveils an area never before recorded acoustically. • We present an acoustic device that can reach 6000 m of depth. • The horizontal beam orientation ensures a constant ensonified sampling volume but adds some artefacts. • Similar scattering layers are detected for coincident frequencies with respect to the vessel echosounder but distinct sublayers are revealed. • Layers' sparsity and avoidance could be potential discriminating properties. • Echointegration can only be applied within dense layers at close range. [ABSTRACT FROM AUTHOR]

Simple Summary: Date stone beetles tunnel into the seeds of several palm species, where they establish brood galleries in which they spend their entire life cycle. Their larvae, which consume the seed's albumen, pupate and hatch in the seed, with multiple generations co-existing until all the seed's albumen has been consumed. Little is known about the initial tunneling and nature of the establishment of the brood galleries. Through experimentation with seeds of the Canary Islands Date Palm, this study shows that the beetles exhibited an overwhelming preference for a penetration at the grooved side. Behavioral observations showed that, in order to penetrate, the date stone beetle needs to be able to push its mandibles into the epicarp of the seed. The main thrust is generated by the hind legs which requires traction as provided by the groove. When tunneling, the mid legs function as a pivot, while the fore legs enable lateral control. When in the tunnel cavity the pair of mid legs act as wall anchors. Gustatory cues prevent the beetle from tunneling through to the other side. The nature of these gustatory cues remains unclear at this point and awaits future research. The cryptic spermatophagus date stone beetle (Coccotrypes dactyliperda Fabricius, 1801) tunnels into palm seeds for oviposition and subsequent establishment of brood galleries. Based on behavioral observations this paper describes the biomechanical and gustatory parameters that govern the initial excavation of the tunnels and the subsequent establishment of the galleries. When tunneling into Canary Islands Date Palm (Phoenix canariensis Chabaud, 1882) seeds, penetration principally occurs at the dorsal side of the seed, in particular the groove, which allows the beetle to gain the required traction. Tunneling is executed in a circular fashion with clockwise or counter-clockwise repositioning in approximately one-eighth to one-quarter turns. Biomechanically, the three pairs of legs provide thrust (hind legs), pivoting (mid legs), and lateral control (fore legs). Gustatory cues, the nature of which remains unclear at this point, prevent the beetle from tunneling through to the other side. [ABSTRACT FROM AUTHOR]

Cumbre Vieja volcano, located in La Palma Island (Canary Islands, Spain), erupted on 19 September 2021. Some papers have been published in the past in which the tsunamis generated by a potential massive landslide due to a collapse of one of the volcano flanks are investigated. However, a potential slide of the lava flow down the island slope has not been considered yet. A numerical model has been applied to simulate the propagation of the tsunami generated by such slide and to assess its consequences in the near field (Canary Islands and west coast of Africa). The model provides maps of maximum wave heights and arrival times of the tsunami, as well as time series of water surface elevation at several selected locations. Since the volume involved in such potential slide is a priori not known, several values were tested and their effects compared. [ABSTRACT FROM AUTHOR]

Despite decadal–millennial repose periods, volcanoes of the Canary Islands pose significant, though poorly understood hazards to local communities and infrastructure. At least 13 volcanic eruptions forming monogenetic cones and lava flows have occurred in the archipelago since 1500 CE: six on the island of La Palma (in 1585, 1646, 1677–1678, 1712, 1949 and 1971), four on Tenerife (1704–1705, 1706, 1798 and 1909), two on Lanzarote (1730–1736 and 1824) and one on the submarine flank of El Hierro (2011–2012). In this paper, we synthesize available data on these historical eruptions, focusing on their physical characteristics and chronological development, and provide new estimates of eruption parameters, such as lava flow runout, area and volume, to inform volcanic hazard assessment in the archipelago. While incomplete and imprecise, historical records indicate that precursory seismicity began days to years prior to eruption onset, consistent with the three months of well-documented unrest for the 2011–2012 eruption. Excluding the atypical 1730–1736 event, eruptions lasted from ten days to a little under five months. Initial eruptive phases usually involved the opening of multiple vents along dike-fed fissures, with Strombolian explosive activity forming monogenetic cones. Lava flow emission generally quickly followed, and later eruptive phases were typically dominated by effusive behavior. Some eruptions (1704–1705, 1824 and 1949), however, had a complex evolution punctuated by the sequential opening of distinct vents several kilometers apart. Total lengths of vent-defined fissures range from 0.2 to 14.0 km, and maximum lava flow runout is 2.7–9.4 km, extending to the coastline in 75% of eruptions. Proximal eruptive deposits cover 1.8–7.8 km2. Published estimates of subaerial eruptive volumes average between 11 and 66 × 106 m3. In comparison, a new empirical relationship based on well-constrained lava flow area and volume data at other basaltic volcanoes yields volumes of 10–76 × 106 m3 for Canary Island eruptions. The 1730–1736 Timanfaya eruption on Lanzarote represents an outlier in the context of historical Canary Island volcanism, with a duration of 2055 days, a total fissure length ≥ 14.4 km defined by at least ten main emission centers, a maximum lava flow length of 21.7 km, a lava flow field area of 146 km2 and volume of at least 2.2–3.7 km3. Historical eruptive rates are low, at 1.0–2.1 × 106 m3/year or 7.3–11.0 × 106 m3/year including the 1730–1736 eruption, in agreement with long-term volcano growth rates based on geologic data. We find no evidence for time-predictable or volume-predictable behavior of the historical eruptive sequence, which has a mean recurrence interval of 39 ± 24 years. Our analysis outlines a useful framework for forecasting the onset, development and style of future eruptions in the archipelago. Further work, particularly detailed field-based studies of eruption deposits and petrologic reconstructions of eruption run-up processes, will help refine our understanding of historical volcanism and associated hazards in the Canary Islands. • 13 historical Canary Island eruptions formed monogenetic cinder cones and lava flows. • Precursory activity may begin days to years prior to eruption, but is poorly constrained. • Eruptions, 10–80 × 106 m3 in volume, commonly show a complex, multi-vent evolution. • An empirical relationship allows estimating volume of basaltic lava flows from their areal extent. • Historical data provide a framework for forecasting future eruption scenarios. [ABSTRACT FROM AUTHOR]

Subtropical cyclones (STCs) are low-pressure systems characterized by having a thermal hybrid structure and sharing tropical and extratropical characteristics. These cyclones are widely studied due to their harmful impacts, in some cases, similar to those caused by hurricanes or tropical storms. From a numerical modeling point of view, they are considered a challenge on account of their rapid intensification. That is the reason why this paper analyzes the simulations of the STC that occurred in October 2014 near the Canary Islands through two high-resolution numerical models: Weather Research and Forecasting (WRF) and HARMONIE-AROME. In this study, the simulations obtained with both models of this STC are analyzed versus different observational data. METAR data are used to validate some surface simulated variables throughout the STC life while soundings are chosen to study the tropospheric behavior. Finally, MSG-SEVIRI satellite brightness temperature is used to be compared to those brightness temperatures simulated by both models to give information of the cloud top spatial structure of this atmospheric system. The 2 m temperature, 2 m dew-point temperature, and 10 m wind speed variables do not show significant deviations when carrying out the validation of both models against the available METAR data. It is outstanding the good results found for the HARMONIE-AROME model when analyzing the temperature sounding for both analyzed dates. Additionally, regarding the wind speed sounding, better results are presented in general by the HARMONIE-AROME model, being the WRF model slightly better during the pre-STC stage. Moreover, the skillfulness of the HARMONIE-AROME model is highlighted when simulating the infrared brightness temperature and cloud distribution compared to the WRF model. • A subtropical cyclone is analyzed using two high-resolution models (WRF and HARMONIE-AROME). • Simulations are assessed against several observational data. • MSG-SEVIRI brightness temperature is compared to the simulations. • Both models show similar results but HARMONIE-AROME performs better in terms of realism and cloud distribution. [ABSTRACT FROM AUTHOR]

The structure and composition of the deep-sea fish community living on the slope off the Canary Islands (eastern-central Atlantic) were investigated. Data were collected by means of eight research cruises (165 stations) at depths between 150 and 2050 m. A total of 4475 fish specimens belonging to 43 families and 78 species (21 Elasmobranchii, 1 Holocephali, and 56 Actinopterygii) were collected with longlines. In the number of individuals, the deep-sea demersal fish fauna was dominated by fishes of the family Synaphobranchidae, followed by Sparidae, Somniosidae, Centrophoridae, and Trichiuridae. The main abundant species were Synaphobranchus affinis , Dentex macrophthalmus , Pagellus acarne , Zameus squamulosus , Aphanopus carbo, Squalus megalops, Centroscymnus coelolepis , and Centroscymnus owstonii. Elasmobranchs, with 1519 individuals, showed a high abundance (33.94%) on the longlines, although their importance increased when the data were analysed by weight, reaching 54.07% (4588 kg), with Zameus squamulosus being the fourth most important species. • Depth was the main structuring factor of deep-sea fish assemblages. • The pattern of assemblages with depth is influenced by the different water masses. • Drastic reduction in species diversity with depth was observed. • The peak in elasmobranch biomass and abundance was observed at approximately 1000 m depth. • Deania calceus , Centroscymnus crepidater or Etmopterus princeps , show a high affinity with colder seawater. [ABSTRACT FROM AUTHOR]