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Copyright of Oceánide is the property of Spanish Society for the Study of Popular Culture (SELICUP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Working out the Old Libyco-Berber (LB) writings found on the Canary Islands (CI) is a long and painstaking task. Scholars have struggled with their provenance, meaning(s), common and different features with North African cognates, scribal communities, and the assumed time-span. In this review-paper, laying theoretical guiding lines for the understanding of the successive patterns and signs is considered an advantage. Nonetheless, high-staked claims as for the origin and the decipherment of the inscriptions are eluded, with plausible scenarios being offered. While corpus enlargement and qualitative and quantitative methods stand for the correct pursuit of the Libyco-Berber scholarship, multi-disciplinary and coordinated research should gain momentum too. [ABSTRACT FROM AUTHOR]

The Canary Islands consist of seven basaltic shield volcanoes whose submerged portion is much more voluminous than the subaerial part of each island. Like so many other volcanic oceanic islands, the indicative deposits of explosive felsic volcanism are not a common feature on the Canary archipelago. Hitherto, they have only been documented from the central islands of Gran Canaria and Tenerife, which are the largest volcanic complexes of the islands. On the other Canary Islands, the presence of felsic rocks is mostly restricted to intrusions and a few lava flows, generally within the succession in the oldest parts of individual islands. In this paper, we present a detailed stratigraphic, lithological and sedimentological study of a significant felsic pumice deposit on the island of El Hierro, referred here as the Malpaso Member, which represents the only explosive episode of felsic volcanism found on the Canary Islands (outside of Gran Canaria and Tenerife). The products of the eruption indicate a single eruptive event and cover an area of about 15 km. This work provides a detailed stratigraphic and chronological framework for El Hierro, and four subunits are identified within the member on the basis of lithological and granulometric characteristics. The results of this study demonstrate the importance of an explosive eruption in a setting where the activity is typified by effusive basaltic events. Given the style and the spatial distribution of the Malpaso eruption and its products, a future event with similar characteristics could have a serious impact on the population, infrastructure and economy of the island of El Hierro. [ABSTRACT FROM AUTHOR]

Southern European countries have come to constitute the most vulnerable external border of the European Union (EU) over the last decade. Irregular migration pressures have been acutely felt on the EU's southern sea borders, and particularly on four sets of islands: Canary Islands (Spain), Lampedusa and Linosa (Italy), Malta, and Aegean Islands (Greece). This quartet is, to a large extent, used as stepping stones by irregular migrants and asylum seekers to reach the European continent. This paper studies the role of these islands as 'outposts' of a framework of externalization. It starts by discussing the notion of externalization and its different facets. It considers how externalization is linked to both fencing and gate-keeping strategies of migration and asylum control. The second part of the paper focuses on the special role of the island quartet with respect to the externalization web cast by national and EU-wide migration policies. It concludes with a critical reflection on the multi-level character of externalization policies and practices that occur both within the EU and between the EU and third countries. [ABSTRACT FROM AUTHOR]

The future success of wave energy in the renewable energy mix depends on the technical advancements of the specific components and systems, on the grid access availability and, ultimately, on the economical profitability of the investment. Small and remote islands represent an ideal framework for wave energy exploitation, due both to resource availability and to the current high cost of electricity that mostly relies on diesel generation. Energy storage can be the enabling technology to match the intermittent power generation from waves to the energy needs of the local community. In this paper real data from La Palma, in the Canary Islands, are used as a basis for the considered test case. As a first step the study quantifies the expected power production from Wave Energy Converter (WEC) arrays, based on data from the Lifesaver point absorber developed by Fred. Olsen. Then, a stochastic optimization approach is applied to evaluate the convenience of energy storage introduction for reducing the final cost of energy and to define the corresponding optimal rating of the storage devices. [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]

The article discusses on the banana plant waste project which can be incorporated into plastics moulded into panels for cars, water tanks, and boat hulls in Canary Islands. It states that a 25,000 tons of banana plant waste is dumped which will then made into a cheap and plentiful raw material to complement conventional plastics. It cites that the Universidad de Las Palmas de Gran Canaria was approached by Canary Islands' farmers who were searching for new ways to dispose of badana.

We present the first release of GTC OSIRIS broad-band data archive. This is an effort conducted in the framework of the Spanish Virtual Observatory to help optimize science from the Gran Telescopio Canarias Archive. Data Release 1 includes 6788 broad-band images in the Sloan griz filters obtained between 2009 April and 2014 January and the associated catalogue with roughly 6.23 million detections of more than 630 000 unique sources. The catalogue contains standard PSF and Kron aperture photometry with a mean accuracy better than 0.09 and 0.15 mag, respectively. The relative astrometric residuals are always better than 30 mas and better than 15 mas in most cases. The absolute astrometric uncertainty of the catalogue is of 0.12 arcsec. In this paper we describe the procedure followed to build the image archive and the associated catalogue, as well as the quality tests carried out for validation. To illustrate some of the scientific potential of the catalogue, we also provide two examples of its scientific exploitation: discovery and identification of asteroids and cool dwarfs. [ABSTRACT FROM AUTHOR]

Copyright of Investigaciones Turisticas is the property of Investigaciones Turisticas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With drupes too acrid for human consumption, Canary Islands Date Palms (Phoenix canariensis) are primarily known for their use as ornamental palms in private and public settings. Little is known about the non-food uses of the leaves, stems and roots of Canary Islands Date Palms. This paper summarises the provisioning services of Canary Island Date Palms. [ABSTRACT FROM AUTHOR]

This article estimates the inequality of opportunity (IO) for the Canary Islands archipelago, a European outermost region of seven islands, including two capital islands and five peripheral islands. To achieve this goal, a survey has been designed to cover a wide range of circumstances, including type of household, socioeconomic background, health status, type of school, family environment, and instilled values during childhood. This new database is one of the main contributions of the paper. For all of the Canary Islands, IO represents approximately 12.4% of total inequality, which is in line with the values found for the South European countries in related studies. However, when we distinguish by type of island, the IO in the peripheral islands accounts for almost 20% of total inequality, which is more in line with Latin American economies. This difference may affect the origin of significant migration flows from the peripheral to the capital islands and future divergence in their development. [ABSTRACT FROM AUTHOR]

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]

As part of the Copernicus Marine Environment Monitoring Service (CMEMS), an operational ocean forecasting system was developed to monitor the ocean dynamics and marine ecosystems of the European waters; and more specifically on the IBI (Iberia-Biscay-Ireland) area. The CMEMS IBI physical-biogeochemical coupled system covers the North-East Atlantic Ocean from the Canary Islands to Iceland, including the North Sea and the Western Mediterranean, with a NEMO-PISCES 1/36° model application. Since its operational launch in April 2018, this CMEMS IBI system has provided a weekly short-term (7-days) forecast of the ocean dynamics and key biogeochemical variables of the marine ecosystem. The main goal of this paper is to assess the performances of the IBI biogeochemical system, using a 7-year retrospective simulation that spans from 2010 to 2016. The model results are validated with available satellite and in situ observations from the International Council for the Exploration of the Sea (ICES), the European Marine Observation and Data Network (EMODnet) and the Biogeochemical-Argo float network. The simulation successfully reproduces the spatial distribution and seasonal cycles of oxygen, nutrients, chlorophyll-a, and net primary production. This simulation can be a useful tool to better understand the current state and changes in the marine biogeochemistry of European waters. It can also provide key variables for developing indicators to monitor the health of European marine ecosystems. These indicators may be of interest to scientists, policy makers, environmental agencies and the general public. [ABSTRACT FROM AUTHOR]

The Canary Islands are an active volcanic region densely populated and visited by several millions of tourists every year. Nearly twenty eruptions have been reported through written chronicles in the last 600 yr, suggesting that the probability of a new eruption in the near future is far from zero. This shows the importance of assessing and monitoring the volcanic hazard of the region in order to reduce and manage its potential volcanic risk, and ultimately contribute to the design of appropriate preparedness plans. Hence, the probabilistic analysis of the volcanic eruption time series for the Canary Islands is an essential step for the assessment of volcanic hazard and risk in the area. Such a series describes complex processes involving different types of eruptions over different time scales. Here we propose a statistical method for calculating the probabilities of future eruptions which is most appropriate given the nature of the documented historical eruptive data. We first characterize the eruptions by their magnitudes, and then carry out a preliminary analysis of the data to establish the requirements for the statistical method. Past studies in eruptive time series used conventional statistics and treated the series as an homogeneous process. In this paper, we will use a method that accounts for the time-dependence of the series and includes rare or extreme events, in the form of few data of large eruptions, since these data require special methods of analysis. Hence, we will use a statistical method from extreme value theory. In particular, we will apply a non-homogeneous Poisson process to the historical eruptive data of the Canary Islands to estimate the probability of having at least one volcanic event of a magnitude greater than one in the upcoming years. This is done in three steps: First, we analyze the historical eruptive series to assess independence and homogeneity of the process. Second, we perform a Weibull analysis of the distribution of repose time between successive eruptions. Third, we analyze the non-homogeneous Poisson process with a generalized Pareto distribution as the intensity function. [ABSTRACT FROM AUTHOR]

A tsunami generated by large-volume landslide can propagate across the ocean and flood communities around the basin. The evolution of landslide-generated tsunamis is affected by the effects of frequency dispersion and involves processes of different temporal and spacial scales. In this paper, we develop a numerical approach employing the weakly nonlinear and fully nonlinear Bossiness-type theories and nested computational grids. The propagation in a large domain is simulated with the weakly nonlinear model in a geographical reference frame. The nearshore wave evolution and runup are computed with the fully nonlinear model. Nested grids are employed to zoom simulations from larger to smaller domains at successively increasing resolutions. The models and the nesting scheme are validated for theoretical analysis, laboratory experiments and a historical tsunami event. By applying this approach, we also investigate the potential tsunami impact on the US east coast due to the possible landslide on La Palma Island. The scenario employed in this study represents an event of extremely low probability. [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: 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]

In lizards, site selection is related to the acquisition of resources such as refuges, mates or prey, but also to the exploitation of sites suitable for thermoregulation. The latter process may be affected by lizard posture and body axis orientation in relation to the sun as a way to optimize heat exchange throughout the day. Specific postures and body orientations could also contribute to more efficient signal transmission in social contexts. In this paper we analyze activity and body axis orientation of adult males and females of the lacertid Gallotia galloti in two localities of Tenerife with different structural habitats. We performed transects at both sampling localities in the morning and at midday during May and June of three years (2002-2004). The numbers of lizards detected per unit time during transects at both localities were similar; however, significantly more males than females were detected. Moreover, more lizards were found oriented parallel or perpendicular to the sun than in alternative (oblique) orientations. Heating rates were not different for copper lizard models oriented parallel or perpendicular to the sun, neither in the morning nor at midday, and there was no significant relationship between air temperature and lizard body orientation. This suggests that lizard body orientation is not constrained by thermoregulatory requirements. We discuss alternative hypotheses and conclude that body axis orientation in G. galloti lizards may reflect a compromise between the conflicting demands imposed by thermoregulation and social communication. [ABSTRACT FROM AUTHOR]

In this paper we describe a fast, specialized hardware implementation of the belief propagation algorithm for the CAFADIS camera, a new plenoptic sensor patented by the University of La Laguna. This camera captures the lightfield of the scene and can be used to find out at which depth each pixel is in focus. The algorithm has been designed for FPGA devices using VHDL. We propose a parallel and pipeline architecture to implement the algorithm without external memory. Although the BRAM resources of the device increase considerably, we can maintain real-time restrictions by using extremely high-performance signal processing capability through parallelism and by accessing several memories simultaneously. The quantifying results with 16 bit precision have shown that performances are really close to the original Matlab programmed algorithm. [ABSTRACT FROM AUTHOR]

This study attempts to answer the question about how firms in an ultra-peripheral region innovate to compete in a global market when they often seem not to have the basic conditions to innovate identified in the literature. On that line, and based on the notion that firms in ultra-peripheral regions must recognise the value of their human capital in order to overcome the limitations typical of their social and geographical context, this research aimed to analyse the relationship between the human resource (HR) policy and innovation in an ultra-peripheral region of the European Union, namely the Canary Islands. The objective of this study is to identify the HR-related internal factors that can affect the innovation capability of firms. In particular, this paper considers the HR management policy, the formalisation of that policy in an HR plan, and job stability. To achieve this goal, an empirical study of 157 Canarian firms was carried out and arrived at the conclusion that high commitment human resource management (HRM) has a positive influence on organisational innovation in processes. The results also show that the formalisation of the HR policy in a plan, and job stability also increases innovation in processes. [ABSTRACT FROM AUTHOR]

Copyright of African Archaeological Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article discusses the theoretical assets of the Lacanian theory of ideology and illustrates its analytical strengths by analysing the anti-immigrant discourse in Tenerife. However, this case study also highlights one of the shortcomings that haunt the Lacanian theory. It will be shown that this theoretical approach is unable to completely account for the grip of ideology. This is due—according to the argument made in this paper—to the psychologistic bias that impoverishes the sociological imagination of the Lacanians. [ABSTRACT FROM AUTHOR]

In this paper we show a fast, specialized hardware implementation of the wavefront phase recovery algorithm using the CAFADIS camera. The CAFADIS camera is a new plenoptic sensor patented by the Universidad de La Laguna (Canary Islands, Spain): international patent PCT/ES2007/000046 (WIPO publication number WO/2007/082975). It can simultaneously measure the wavefront phase and the distance to the light source in a real-time process. The pipeline algorithm is implemented using Field Programmable Gate Arrays (FPGA). These devices present architecture capable of handling the sensor output stream using a massively parallel approach and they are efficient enough to resolve several Adaptive Optics (AO) problems in Extremely Large Telescopes (ELTs) in terms of processing time requirements. The FPGA implementation of the wavefront phase recovery algorithm using the CAFADIS camera is based on the very fast computation of two dimensional fast Fourier Transforms (FFTs). Thus we have carried out a comparison between our very novel FPGA 2D-FFTa and other implementations. [ABSTRACT FROM AUTHOR]

Since May 2006, the two STELLA robotic telescopes at the Izaña observatory in Tenerife, Spain, delivered an almost uninterrupted stream of scientific data. To achieve such a high level of autonomous operation, the replacement of all troubleshooting skills of a regular observer in software was required. Care must be taken on error handling issues and on robustness of the algorithms used. In the current paper, we summarize the approaches we followed in the STELLA observatory. [ABSTRACT FROM AUTHOR]

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Author-supplied Abstracts.)

The Canaries have recently served as a test-bed island system for evaluating newly developed parametric biogeographical methods that can incorporate information from molecular phylogenetic dating and ages of geological events. To use such information successfully, knowledge of geological history and the fossil record is essential. Studies presenting phylogenetic datings of plant groups on oceanic islands often through necessity, but perhaps inappropriately, use the geological age of the oldest island in an archipelago as a maximum-age constraint for earliest possible introductions. Recently published papers suggest that there is little chance of informative fossil floras being found on volcanic islands, and that nothing could survive violent periods of volcanic activity. One such example is the Roque Nublo period in Gran Canaria, which is assumed to have caused the extinction of the flora of the island ( c. 5.3–3.7 Ma). However, recent investigations of Gran Canaria have identified numerous volcanic and sedimentological settings where plant remains are common. We argue, based on evidence from the Miocene–Pliocene rock and fossil records, that complete sterilization of the island is implausible. Moreover, based on fossil evidence, we conclude that the typical ecosystems of the Canary Islands, such as the laurisilva, the Pinus forest and the thermophilous scrubland, were already present on Gran Canaria during the Miocene–Pliocene. The fossil record we present provides new information, which may be used as age constraints in phylogenetic datings, in addition to or instead of the less reliable ages of island emergences or catastrophic events. We also suggest island environments that are likely to yield further fossil localities. Finally, we briefly review further examples of fossil floras of Macaronesia. [ABSTRACT FROM AUTHOR]

Tourism to the Canary Islands is centred around competitively priced holidays focused on the sun and beach mass tourism experience. A restructure of the islands' wine industry offers opportunities for developing new tourism alternatives based on gourmet products and traditional landscapes. This paper examines the potential of wine tourism from winery operators' perspectives. Challenges to overcome in the development of a successful sustainable local wine tourism industry include the need for expansion of the destination image to reflect the region's wine-making history and scenic qualities; a shift towards independent high-yield travellers; and reintroducing local produce in the mass tourism product. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aim The presence of numerous reliable fossils and the occurrence of many endemic island species make the Boraginales particularly suitable for integrative biogeographical studies. In this paper we aim to elucidate the time frame and events associated with the origin of selected borages endemic to the Mediterranean climate zone. More specifically, we describe and examine the alternative palaeo- and neoendemic hypotheses for their origin. Location Corsica and Sardinia (continental fragment islands) and the Canary Islands (an oceanic island archipelago). Methods Eighty-nine accessions, representing 30 genera from five families ascribed to the Boraginales, were examined for six chloroplast DNA regions. We used an integrative approach including phylogenetic analyses (MrBayes), Bayesian molecular dating (T3 package) with four fossil constraints on nodes, and biogeographical reconstructions (diva) to elucidate the temporal and spatial origins of the Corso-Sardinian and Canary Island endemics. Results Species of Echium endemic to the Canary Islands diverged from their continental sister clade during the Miocene (15.3 ± 5.4 Ma), probably after the rise of the oldest islands ( c. 20 Ma). Corso-Sardinian endemics of Borago diverged from their primarily North African sister clade during the late Miocene-Pliocene ( c. 6.9 ± 3.6 Ma), well after the initial fragmentation of the islands ( c. 30 Ma). Similarly, Corso-Sardinian endemics of Anchusa diverged from the South African Anchusa capensis during the Pliocene–Pleistocene ( c. 2.7 ± 2.1 Ma). Main conclusions The present study reveals an Anatolian origin for Anchusa, Borago and Echium and underlines the importance of the Eastern Mediterranean region as a possible reservoir for plant evolution in the Mediterranean Basin. For Anchusa and Borago, the divergence from their respective sister clades on the two types of islands post-dated the formation of the islands, thus supporting the neo-endemic hypothesis, whereas the dating results for the origin of Echium endemics were less conclusive. [ABSTRACT FROM AUTHOR]

The Bradford Robotic Telescope (BRT) is located on Mount Teide at Tenerife and is working, taking observations since 2003. It is a fully automated telescope. The hardware and software used for the working of the telescope are described here. Twenty four BL Lac objects are observed since 2005 and magnitudes of the objects are calculated. We describe in this paper the working of BRT and optical BVR photometry of BL Lac objects, observed during 2005–2007. [ABSTRACT FROM AUTHOR]

This paper presents a brief review of archaeological evidence for the impact of the pre-Hispanic population on the environment of the Canary Islands. Prior to human colonisation, the archipelago was an untouched environment with high botanical and faunal biodiversity. The first human settlement can be traced to the early 1st millennium BC; this period of settlement finished at the end of the 15th century AD when the Spanish Crown conquered the archipelago. It has often been assumed that the pre-Hispanic population had little significant impact on the islands' ecosystems. However, abundant evidence for faunal extinctions, deforestation and soil erosion has been recovered from archaeological sites across the islands. This indicates that pre-Hispanic colonisers introduced cultivated plants, opened up the forests to create fields and cut woody vegetation for fuel. They also introduced domestic animals and alien predators resulting in a major depletion of native fauna. [ABSTRACT FROM AUTHOR]

Aim Areas of endemism are the fundamental units of cladistic biogeographical analysis but there is no consensus on the most appropriate method for their delimitation. In this paper, the relative performance of a number of algorithmic approaches for the delimitation of areas of endemism is investigated within the context of the Canary Islands flora, and areas of endemism within the Canary Islands archipelago are defined. Location The Canary Islands. Methods A data matrix comprising the distributions of 609 endemic spermatophyte taxa ( c. 90% of the endemic flora) scored on a 10 × 10 km UTM grid was analysed using: (1) UPGMA (unweighted pair group method with arithmetic mean) clustering of Jaccard and Kulczynski similarity coefficient matrices, (2) parsimony analysis of endemicity (PAE), and (3) the programndm (eNDeMism). The performance of each method was then determined by the extent to which the resulting areas of endemism met three criteria: (1) possession of two or more strict endemic taxa, (2) diagnosability, and (3) geographical contiguity. Results Each of the four methods resulted in substantially different sets of areas.ndm analysis resolved 17 areas of endemism consistent with all three criteria, and collectively these accounted for 59% of all cells. In the hierarchical analyses none of the methods recovered more than eight areas of endemism, and the total coverage of cells ranged from 13% to 33% when the results were confined to intra-island areas of endemism. Main conclusions ndm outperforms hierarchical clustering methods in terms of both the number of intra-island areas of endemism delimited that meet the three evaluation criteria and the total coverage of those areas.ndm may also be considered preferable because it is non-hierarchical, incorporates spatial information into the delimitation of areas, and permits overlap between areas of endemism where there is evidence to support it. The results support the use ofndm as the most appropriate method currently available for the delimitation of areas of endemism. The areas of endemism identified by thendm analysis are discussed. [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]

Aim This paper has three aims: (1) to reconstruct the colonization history of two peripheral populations of the trumpeter finch ( Bucanetes githagineus) presumably originating from the same source, one the result of an ancient expansion process and the other recently established and still expanding; (2) to estimate the importance of key events, such as past and current gene flow and bottlenecks, in both expansion processes and their contribution to the present population structure and genetic diversity; and (3) to find out whether two peripheral populations that established at widely differing times also differ in terms of genetic diversity. Location Northwest Africa (assumed source population), Canary Islands (long-established peripheral) and south-eastern Iberian Peninsula (recently established peripheral). Methods Bayesian analysis of population structure, individual assignment tests, F-statistics, maximum likelihood migration estimates, genetic diversity indices and bottleneck tests were calculated with microsatellite data from 194 trumpeter finches from five breeding and two seasonal non-breeding sites. Results Our data support the existence of two subpopulations (Canary Island and Ibero-African) as the most likely population structure. Seasonal sites in the Iberian Peninsula had the highest percentage of birds assigned to other, mainly Iberian, sites. Pairwise FST values showed that the Canary Island localities were very similar to each other, but differed from the rest. Gene flow estimates within subpopulations were only slightly higher in the Canary Island population than in the Ibero-African one. Gene diversity indices were similar at all localities. Canary Island sites show evidence of bottlenecks, whereas the Ibero-African sites do not. Main conclusions Our data show that, at present, birds from the Canary Islands are genetically differentiated from those in North Africa and continental Spain. We could not unequivocally confirm the African origin of Canary populations because the contrary is also plausible. The Iberian Peninsula seems to have repeatedly received individuals from North Africa, which would have led to the relatively high genetic diversity found in these recently established localities and prevented bottlenecks. Movements of individuals towards sites outside their current range during the non-breeding season are likely to precede the establishment of new breeding sites at the periphery of the distribution range. [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]

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Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part of regulatory processes. The assessment of exposure to mercury shown in this paper has been performed by means of a study on the whole diet. Total mercury (Hg) levels were determined by cold vapour atomic absorption spectrometry (AAS) in 420 samples of regularly consumed food and drink. The total Hg concentrations measured in the different groups of food ranged from non-detectable to 119 µg kg-1 w/w. The fish group had the highest concentrations of total Hg. All groups of food with regulated Hg content showed levels that were lower than the legally set values. The food consumption data used in the analysis were taken from the latest nutritional survey made in the Canary Islands, Spain. The estimated total Hg intake of local population (5.7 µg/person day-1) did not exceed the provisional tolerable weekly intake (PTWI) limit of 0.3 mg week-1 of total mercury (43 µg/person day-1) fixed by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives. Fishery products contributed 96% of the total Hg intake. The mean Hg intake for each island in this archipelago, formed by seven, has also been calculated. Fuerteventura, Lanzarote and El Hierro are the islands with the highest level of Hg intake (7.0, 7,0 and 6.1 µg/person day-1, respectively). La Palma Island, due to its low fish consumption, had the lowest level of Hg intake (4.5 µg/person day-1), followed by La Gomera (5.4 µg/person day-1), Tenerife (5.5 µg/person day-1) and Gran Canaria (5.6 µg/person day-1). A comparison has been made of the results obtained in this study with those found for other national and international communities. [ABSTRACT FROM AUTHOR]

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]

Carbon dioxide is one of the first gases to escape the magmatic environment due to its low solubility in basaltic magmas at low pressures. The exsolved CO2 gas migrates towards the surface through rock fractures and high permeability paths. If an aquifer is located between the magmatic environment and the surface, a fraction of the CO2 emitted is dissolved in the aquifer. In this paper, an estimation of the water mass balance and the CO2 budget in Las Cañadas aquifer, Tenerife, Canary Islands, is presented. Magmatic CO2 is transported by groundwater and discharged through man-made sub-horizontal drains or galleries that exist in this island, and by the flow of groundwater discharged laterally towards other aquifers or to the ocean. In addition, the pCO2 at the gallery mouth (or entrance) and at the gallery bottom (internal and deepest discharge point where the gallery starts) are calculated and mapped. The total CO2 advectively transported by groundwater is estimated to range from 143 to 211 t CO2 d−1. Considering that the diffuse soil emission of CO2 for the same area is 437 t d−1, the diffuse/dissolved CO2 flux ratio varies between 2 and 3. The high dissolved inorganic carbon content of groundwater explains the ability of this low temperature hydrothermal water to dissolve and transfer magmatic CO2 at volcanoes, even during quiescence periods. [ABSTRACT FROM AUTHOR]

Considerable attention has been given in the economic literature to Dutch disease, with symptoms of the disease being extensively described inmany different contexts. Dutch disease is a condition which describes the reaction of an economy, subject to rapid change, on finding new export uses for natural resources. None of the studies, however, has focused on the tourist industry as a source of increased wealth through the exploitation of natural resources, such as beaches or natural areas, using typical mass models of tourism development. By examining two different Spanish regions, this paper provides evidence that the Balearics and the Canary Islands, whose economies are heavily orientated towards tourism, both show signs of Dutch disease and that, as a result, their economic growth might be compromised in coming years. [ABSTRACT FROM AUTHOR]

This paper offers a detailed taxonomic revision of all Canarian Pholcus species described before 2003, all of which are newly described and newly illustrated. Pholcus guadarfia sp. nov. is described, while a neotype for Pholcus malpaisensis Wunderlich, 1992 is also provided. In addition, we propose Pholcus gomerae Wunderlich, 1980 as a senior synonym for Pholcus gomeroides Wunderlich, 1987. More importantly, cladistic analysis based on the morphological characters of the Macaronesian Pholcus species was conducted for the first time. Parsimony analyses of 73 morphological characters revealed the close relationships between those species from the Canary Islands, Madeira and the Macaronesian enclave in Africa (between Agadir and Nouadhibou). © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151, 59–114. [ABSTRACT FROM AUTHOR]

Aim The aim of this paper is to identify the patterns in the morphological differentiation in Canary Island mice, based on fossil and modern samples. In order to achieve this, the mouse species present on the archipelago were first compared with a set of continental mice. The differences between the continental and Canary Island samples, and among the Canary Island samples, provide insights into the processes of colonization and the subsequent insular evolution. Location Canary archipelago. Methods An outline analysis based on Fourier transformation was used to quantify shape differences between lower molars. Together with the fossil and modern Canary Island samples, a reference set of genotyped continental populations of the commensal Mus musculus and the wild Mus spretus was used for comparison. Results The morphometric analysis showed that all the mouse specimens from the Canary Islands and Cape Verde belonged to Mus musculus domesticus. Lower molars of extant mice from La Gomera, El Hierro, Gran Canaria, Tenerife, and to a lesser degree from Lanzarote, were similar to those of genotyped M. m. domesticus from the continent, while teeth of extant mice from Fuerteventura were more divergent. Fossil mice from Fuerteventura were very similar to the extant representatives on this island, and similar to the fossil mice on the nearby islands of Lobos and La Graciosa. Main conclusions The mouse present on the Canary archipelago has been identified as the house mouse M. m. domesticus. Based on the shape of the lower molar, the Canary Island mice are divergent from the continental ones, but the degree of divergence varies with the geography of the archipelago. Overall, populations from eastern islands are more divergent from the continental mice than populations from western ones. Fossil populations indicate that this situation was established several centuries ago. Two main factors may have contributed to this pattern: the appearance of different types of environment on the islands since the successful settlement of the mouse, and/or the number of subsequent introductions of continental individuals via shipping. [ABSTRACT FROM AUTHOR]

The siphonostomatoid family Asterocheridae Giesbrecht, 1899 uses a wide range of host phyla, mainly due to the host diversity of two genera - Asterocheres Boeck, 1859 and Orecturus Humes, 1992. In the present paper, two new asterocherid species from the eastern Atlantic are described and compared with their congeners. One of these species belongs to the genus Asterocheres, A. madeirensis, and was found associated with the sponge Petrosia ficiformis (Poiret, 1789) in Madeira Island. This sponge occurs both in the Mediterranean and on nearby Atlantic coasts, although currently there are no records of the presence of symbiotic asterocherids for its Mediterranean populations. The second new species, Orecturus canariensis, is the first record of the genus on the eastern Atlantic coasts and was found in association with the gorgonian Villogorgia bebrycoides (Koch, 1887) in the Canary Islands. The diagnosis of the genus Orecturus is slightly modified to include some features shown by this new species and some of its plesimorphic and derived characteristics compared with the remaining asterocherid genera. Although the gorgonian Paramuricea grayi (Johnson, 1861) occurs in the same ecological assemblages as the infested colonies of V. bebrycoides, no specimens of asterocherid copepods were found on Paramuricea colonies. Therefore, O. canariensis may be a monoxenous symbiont. [ABSTRACT FROM AUTHOR]

Aim The aim of this paper is to investigate the causes of the current restricted distribution of a narrow-range endemic bird species, the Canary Islands stonechat, Saxicola dacotiae. Location Eastern islands of the Canary Islands archipelago. Methods We compared climatic patterns (temperature and rainfall), habitat and microhabitat structure, food availability during a full annual cycle, and the abundance of native avian competitors and predators inside and outside the species’ range. Three study areas, located in similar habitats on nearby islands, were studied: northern Fuerteventura, close to the northern border of the species’ range; southern Lanzarote, 22 km from the nearest site occupied by stonechats; and the Lobos islet, 10 km from the nearest occupied site and 2 km from the coast of Fuerteventura. Results The cover of suitable habitats (slopes with high cover of large shrubs, stony fields and ravines) and microhabitats (shrubs and boulders) and the abundance of arthropods during the breeding period of Canary Islands stonechats were lower outside than inside the species’ range. Temperature, rainfall and the abundance of competitors and predators inside and outside the species’ range did not differ significantly. Main conclusions Ecological requirements explaining the distribution of the Canary Islands stonechat within its range seem to be the main factor hindering its settlement on nearby islands. Geological and palaeoclimatic processes, as well as past and current human impact, could also have constrained the distribution of this narrow-range endemic bird species. [ABSTRACT FROM AUTHOR]

Aim Mac Nally and Lake proposed a statistic ( η) for determining whether the diversity in archipelagos is better generated by several small patches (SS-dominance) or by a few large patches (SL-dominance). The η statistic improves the study of the generation of diversity in systems of patches, but the dependence of η on a particular species–area relationship may reduce its effectiveness. In this paper we show that η may be affected by the criterion used to distinguish between large and small patches. We propose alternative measures (ranked m-dominance indices) for the detection of SS/SL dominance, which separate the effects of each class of patch size on the generation of diversity. Location We use previously published species lists from three archipelagos: lizard species on 25 islands in the Gulf of California; non-introduced species of reptiles of the Canary Islands (order Squamata); and finch species from 19 islands of the West Indies. We also use one artificial data set. Methods Presence–absence data and the rank order of patch areas are used to define the m-dominance indices, interpreted as measures of preferential size of patches occupied by m species. A Monte Carlo procedure is implemented for testing the significance of the observed indices. Row and column totals in the simulated presence–absence matrices are kept fixed in order to maintain differences in species richness among sites and differences in occurrence frequencies among species, but the allocation of each occurrence to a specific ranked area is randomized. The analyses are exemplified with the three published data sets taken from the literature, and a hypothetical patch system neither SS- nor SL-dominated. Results The new m-dominance indices identified correctly the hypothetical patch system, while η was positive, suggesting an incorrect SL-dominant result. For the lizard data set, the standardized ranked m-dominance was significantly large for small m, confirming an SL-dominated system. Islands of varying size in the Canary archipelago hosted restricted reptile species, but matrix sparseness seems to have caused the non-significant results for the m-dominance indices in this case. The overall pattern of the West Indies system shows that medium-large islands are dominant, but most Monte Carlo analyses were not significant, also possibly as a result of matrix sparseness. Main conclusions The m-dominance indices have the virtue of summarizing composition–area relationships, and including Monte Carlo procedures for testing whether patch size and the type of species distribution (species restricted to m patches, m = 1,..., s) are random or not . When m is as low as 1 or 2, the m-dominance indices may typify the role of restricted species on the generation of diversity in the system of patches. The procedure developed here can be generalized to include other ordinal properties of patches, such as isolation or habitat heterogeneity. [ABSTRACT FROM AUTHOR]

Gabbro xenoliths reported in this paper were collected in northern Fuerteventura, the Canary Island located closest to the coast of Africa. The xenoliths are very fresh and consist of Ti–Al-poor clinopyroxene + plagioclase (An87–67) + olivine (Fo72–86) ± orthopyroxene. Clinopyroxene and orthopyroxene are constantly and markedly depleted in light rare earth elements (LREE) relative to heavy REE (HREE), as expected for cumulus minerals formed from highly refractory N-MORB-type melts. In contrast, whole-rock Primordial Mantle-normalized trace element patterns range from mildly S-shaped (mildly depleted in Pr–Sm relative to both the strongly incompatible elements Rb–La and the HREE) to enriched. Estimates show that the trace element compositions of the rocks and their minerals are compatible with formation as N-MORB gabbro cumulates, which have been infiltrated at various extents (≤1% to >5%) by enriched alkali basaltic melts. The enriched material is mainly concentrated along grain boundaries and cracks through mineral grains, suggesting that the infiltration is relatively recent, and is thus associated with the Canary Islands magmatism. Our data contradict the hypothesis that a mantle plume was present in this area during the opening of the Atlantic Ocean. No evidence of continental material that might reflect attenuated continental crust in the area has been found. Gabbro xenoliths with REE and trace element compositions similar to those exhibited by the Fuerteventura gabbros are also found among gabbro xenoliths from the islands of La Palma (western Canary Islands) and Lanzarote. The compositions of the most depleted samples from these islands are closely similar, implying that there was no significant change in chemistry during the early stages of formation of the Atlantic oceanic crust in this area. Strongly depleted gabbros similar to those collected in Fuerteventura have also been retrieved in the MARK area along the central Mid-Atlantic Ridge. The presence of N-MORB oceanic crust beneath Fuerteventura implies that the continent–ocean transition in the Canary Islands area must be relatively sharp, in contrast to the situation both further north along the coast of Morocco, and along the Iberian peninsula. [ABSTRACT FROM AUTHOR]

As human demands for water have become more intense in modern times, the Canary Islands have become a difficult environment for all the macroinvertebrate fauna dependent upon running water for their survival; few permanent streams remain. Investigations on the simuliid (blackfly) fauna have shown, however, that at least six species exist in the archipelago, but that one, the endemic Simulium paraloutetense , known only from one site now destroyed, is possibly extinct. The paper presents cumulated data on distribution and material obtained over the past 33 years (since aquatic-stage specimens from breeding sites were first collected) with the aim of providing a baseline against which future studies of the Canarian simuliid fauna can be assessed. Revised identification keys for larvae and pupae are given to aid such monitoring. Remarks concerning each species include notes on chromosomal data when these are available. Comments are included on some aspects of the lotic habitats and island colonization. [ABSTRACT FROM AUTHOR]

This paper describes design, observation methodology, results and interpretation of the GPS surveys conducted in the areas of the N-W of Tenerife where deformation was detected using InSAR. To avoid undesirable antenna positioning errors in the stations built using nails, we designed and used calibrated, fixed-length metal poles, allowing us to guarantee that the GPS antenna was stationed with a height repeatability of the order of 1 mm and of less than 3 millimeters on the horizontal plane. The results demonstrate that this system is ideal for field observation, especially to detect small displacements that might be masked by accidental errors in height measurements or centering when observed with a tripod. When observations were processed, we found that using different antenna models in the same session sometimes causes errors that can lead to rather inaccurate results. We also found that it is advisable to observe one or two stations in all the sessions. The results have reconfirmed the displacement in the Chío deformation zone for the period 1995–2000 and indicate a vertical rebound from 2000 to 2002. They also confirm that the subsidence detected by InSAR to the south of the Garachico village has continued since 2000, although the magnitude of the vertical deformation has increased from around 1 cm to more than 3 cm a year. Detected displacements could be due to groundwater level variation throughout the island. A first attempt of modelling has been made using a simple model. The results indicate that the observed deformation and the groundwater level variation are related in some way. The obtained results are very important because they might affect the design of the geodetic monitoring of volcanic reactivation on the island, which will only be actually useful if it is capable of distinguishing between displacements that might be linked to volcanic activity and those produced by other causes. Even though the study was limited to a given area of Tenerife, in the Canary Islands, some conclusions apply to, and are of general interest in similar geodynamic studies. [ABSTRACT FROM AUTHOR]

This paper is concerned with climate change in the region of the Canary Islands and the potential implications for the laurel forests of Tenerife. Frequent orographic cloud formation during the dry season is of vital importance to the altitudinal distribution of the laurel forests, because it maintains a semi-humid environment in the otherwise semi-arid climate of the Canary Islands. The distinctive environmental conditions in conjunction with the location of the Canary Islands on the Northern poleward edge of the Hadley Circulation make these ecosystems potentially highly sensitive to regional changes in climatic conditions. To explore this sensitivity, we first quantify observed trends in humidity and temperature across an altitudinal transect at the base of the Anaga peninsular, and second, analyse the results of three GCM experiments (CGCM1, ECHAM4 and CSIRO) to develop alternative climate change scenarios, and third, use these data to assess likely shifts in the elevational distribution of the laurel forest climate envelope. We report a significant increase in relative humidity and decreases in the diurnal temperature range on Tenerife at altitudes below the trade wind inversion within the last 30 years during the thy season, which suggests an increased occurrence of low-level clouds. There is also partial evidence for a drying trend across the trade wind inversion, which may be linked to an increased subsidence. Overall, the models suggest a downward shift of the area climatically suitable for laurel forests, which may be driven by changes in temperature and moisture supply in the region as well as by larger-scale changes in the atmospheric circulation. Our findings contrast with previously published findings for a tropical montane cloud region, which predict an upward shift of the cloud base. This suggests, following the assumptions inherent in the models applied, that the ecological consequences of climate change for cloud forests may be linked to their relative location in the Hadley Circulation. [ABSTRACT FROM AUTHOR]