Search

This research evaluates the capability of Sentinel-2 satellite imagery for mapping Cymodocea nodosa meadows in El Médano (Tenerife, Canary Islands, Spain). A Level-1C image from 27 October 2022 was used. Atmospheric correction was addressed using the Sen2Cor tool, while Lyzenga's method was employed to account for the water column effect. Three supervised classifications were performed using Random Forest, K-Nearest Neighbors (KNN) and KDTree-KNN algorithms. These classifications were complemented by an unsupervised classification and in situ data. Additionally, the amount of blue carbon sequestered by the C. nodosa in the study area was also estimated. Among the classifiers, the Random Forest algorithm produced the highest F1 scores, ranging from 0.96 to 0.99. The results revealed an average area of 237 ± 5 ha occupied by C. nodosa in the study region, translating to an average sequestration of 111,000 ± 2000 Mg CO2. Notably, the seagrass meadows in this study area have the potential to offset the CO2 emissions produced by the industrial combustion plant sector throughout the Canary Islands. This research represents a significant step forward in the protection and understanding of these invaluable ecosystems. It effectively underlines the potential of Sentinel-2 satellite data to map seagrass meadows and highlights their crucial role in achieving net zero carbon emissions on our planet. [ABSTRACT FROM AUTHOR]

The Canary Islands are heavily dependent on fossil fuels which intensifies the need for a decarbonisation pathway by 2050. Our study provides a comprehensive approach to identify possible energy transition pathways in line with different stakeholder perspectives. We conducted two rounds of 16 foresight interviews in the region with stakeholders representing different groups. The first round focused on understanding the current challenges and opportunities of the energy system, while the second round aimed at identifying the overall vision of the stakeholders for their local energy system. We have found that there are still significant regulatory difficulties that hinder implementation of technologies and innovative business models. However, the main challenges highlighted were achieving a transition without energy justice and the lack of collaboration between stakeholders. Different pathways have been identified but all interviewees emphasised that the future energy system needs to be human-centred and support citizen participation, prosumers, and energy communities. [ABSTRACT FROM AUTHOR]

Energy production and consumption represent the most significant sources of CO2 emissions in the world. An isolated island scenario like the case of the Canary Islands, where dependence on fossil fuels is almost complete needs an effective integrative strategy for energy efficiency in order to reduce the carbon footprint. The objective of our work is to design an integrative and sustainable energy transition strategy in the hotel sector of the Islands. To achieve this, we implement a qualitative / quantitative technique called Q methodology. Our study was conducted with a carefully selected group of 31 experts from diverse areas related to the energy sector who were asked to rank-order their degree of agreement or disagreement with 30 key energy discourses (statements). The results of our analysis identify four profiles of stakeholders' mindsets: the "Low-carbon", the "Techies", the "Skeptics" and the "Trusting". A well-defined integrative strategy could be identified which includes self-consumption using renewable energies; simplification of the administrative procedures; promotion of the use of heat pumps, among others. A further interesting consensus result among all four groups reveals experts' uncertainty regarding the post-COVID-19 reality. [ABSTRACT FROM AUTHOR]

The central objective of this study is to explore the causes of delayed flights at Spanish airports and to examine them in further detail while taking into consideration additional factors. All the data originated from the internal database of an airline operating in the European area, widely used by Spanish airports for both regular and charter flights. Since the database consists mainly of linguistic variables, contingency tables and correspondence analysis were used for processing of the data. It was established in our research that there is a higher number of delayed flights in mainland Spain and the Balearic Islands, and lower in the Canary Islands. The most common reason for delayed flights at all airports is the propagation of the delay from previous flight, mostly on the Ibiza Island. Delays caused by the airport, air traffic control, and emergency situations are most frequent in Barcelona. At all airports the frequency of delays apparently decreases with their length, in other words – the shorter the delay, the more frequently it occurs. The longest delays are usually caused by the delay of the previous flight, and this cause seems to occur more frequently in the afternoon and in the evening, due to the propagation of delays over the course of the day. [ABSTRACT FROM AUTHOR]

This work presents a first comparative study of the Lidar Ratio (LR) values obtained for dust particles in two singular dust-influenced regions: the Canary Islands (Spain, close to the African coast in the North Atlantic Ocean), frequently affected by Saharan dust intrusions, and the Kuwait area (Arabian Peninsula) as usually influenced by Arabian dust storms. Synergetic lidar and sun-photometry measurements are carried out in two stations located in these particular regions for that purpose. Several dusty cases were observed during 2014 in both stations and, just for illustration, two specific dusty case studies have been selected and analyzed to be shown in this work. In general, mean LR values of 54 sr and 40 sr were obtained in these studies cases for Saharan and Arabian dust particles, respectively. Indeed, these results are in agreement with other studies performed for dust particles arriving from similar desert areas. In particular, the disparity found in Saharan and Arabian dust LR values can be based on the singular composition of the suspended dust aerosols over each station. These results can be useful for CALIPSO extinction retrievals, where a single LR value (40 sr) is assumed for pure dust particles independently on the dust source region. [ABSTRACT FROM AUTHOR]

The study has been carried out in the Garajonay National Park, a UNESCO World Heritage, located in the center and north of the island of La Gomera, one of the Canary Islands. This National park has several ancient ritual places, which after the archaeological excavations in the 1950's have been partly reconstructed. One of the most valuable discoveries during these excavations was the Circular stone. A nondestructive study method has been used to analyze the surface of this stone. The detailed photo documentation and further assessment of the exposed surfaces of the stone was performed in order to identify artificially made deformations of the stone surface as evidence left by ancient people. The elaborated methodology allowed us to identify and group human made carvings, nowadays visible as separate lines and their groups, as well as fragments of signs and symbols. Such approach could also be applied in the studies of other poorly preserved stone material objects. [ABSTRACT FROM AUTHOR]

The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. With 17m diameter mirror dishes and ultra-fast electronics, they provide the lowest energy threshold among existing IACTs. Reaching down to 50 GeV in standard trigger mode, it is the only IACT that can close the energy gap between satellite-borne and ground-based observations. In this paper we present recent scientific highlights of MAGIC including morphology studies of SNR W51C, detection of Crab pulsar at energies above 100 GeV, detections of new sources and results from studies of sources in flaring state. We also present the current status of the MAGIC upgrade program. [ABSTRACT FROM AUTHOR]

The Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes are two 17 m diameter Cherenkov telescopes, located on the Canary island La Palma (Spain), with an optimal view on the Northern sky. MAGIC-I was operating as a single telescope since fall 2004, until 2009 when the construction of the second telescope MAGIC-II was completed. It is nowadays the only ground-based instrument able to measure high-energy γ-rays below 100 GeV. MAGIC carries out a physics program which includes many topics from astrophysics and fundamental physics. These proceedings focus on the latest MAGIC results related to cosmology and relativistic physics, such as: Extragalactic Background Light, indirect Dark Matter searches and Quantum Gravity. [ABSTRACT FROM AUTHOR]

The 17 m diameter MAGIC telescope, located on the Canary island of La Palma, is the largest single-dish Cherenkov telescope for unveiling the gamma-ray universe. It reaches the lowest energy threshold among ground-based gamma-ray observatories: 55 GeV for normal observations, and as low as 25 GeV using a dedicated trigger system developed for pulsar observations. MAGIC also features a unique fast follow-up capability for tracking transients like gamma-ray bursts. Since Fall 2004 MAGIC has been taking data routinely, successfully detecting different classes of VHE sources like pulsar wind nebulae, gamma-ray binaries, pulsars, active galactic nuclei and radio galaxies. Here we review some of the most relevant results from recent observations, and report about the status of MAGIC-II, a stereoscopic extension by a second 17-m telescope already in operation. [ABSTRACT FROM AUTHOR]

The 17 m diameter Cherenkov telescope MAGIC, located on the Canary Island of La Palma, has the lowest trigger threshold among operating Cherenkov telescopes; this makes it a very promising tool for the detection of the pulsed gamma-ray (γ-ray) emission from ground. Recently, a new analog summation trigger concept, which allows reducing the threshold even further, has been designed and implemented. The analog signals of patches in the camera, comprising 18 pixels each, are summed up in the analog mode. In order to prevent triggers from photomultiplier (PMT) afterpulses, the individual pixel signals are clipped at a preset amplitude level and then added up. The average FWHM of the time duration of signals induced by cosmic rays is 2.6 ns. This allows one to keep the coincidence time window very small and thus to strongly suppress accidental triggers. In the usual digital trigger designs, the signal should be above a certain threshold from each individual pixel to contribute to the trigger. In the summation trigger all low amplitude signals in a given patch in the camera are summed up and fully contribute to the trigger. The new trigger concept provides a low cost trigger for Cherenkov telescopes and it is very effective and stable. This trigger system for the MAGIC telescope was installed in October 2007 and was successfully used in the detection of the Crab Pulsar above 25 GeV. [ABSTRACT FROM AUTHOR]

The HEGRA collaboration operates a system of 5 Cherenkov telescopes on the Canary Island of La Palma for Gamma-Ray Astronomy in the energy range above 500 GeV. Based on the stereoscopic observation of air showers induced by cosmic gamma-rays in the atmosphere of the earth with at least two telescopes, the system achieves an angular resolution of 0.1° and an energy resolution of 20% per individual gamma-ray, as well as an energy flux sensitivity ν F[sub ν] at 1 TeV of 10[sup −11] ergs/cm² s for one hour of observation time. Since its commissioning in fall 1996 the system has been used to study in detail the temporal and spectral characteristics of the BL Lac objects Mkn 501 and Mkn 421. In this contribution we highlight recent observational results. [ABSTRACT FROM AUTHOR]

The first imaging Cherenkov telescope of the HEGRA collaboration (CT1) detects VHE gamma rays in stand-alone mode. Last year CT1 was equipped with new high-reflectivity mirrors and a next-neighbor trigger which have enabled reduction of the energy threshold to around 700 GeV. In addition completely new software for the data acquisition has been developed and installed in the past months. Here we report on the features of the new system and some of the tests which have been performed with it. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Our Tuorla Observatory has a long tradition in the optical blazar monitoring. To increase our data coverage our Observatory has rented a 60cm optical telescope (hereafter KVA-telescope) on La Palma from the Royal Swedish Academy of Sciences. This telescope is located quite close to the 4.2m WHT-telescope. The weather conditions on La Palma are normally excellent with about 300 clear nights per year. Our plan is to modernize the telescope so that finally it should be totally robotic. We are planning to use more than 70 % of the observing time for the support observations for the future gamma experiments like MAGIC, INTEGRAL, AGILE and GLAST. We have already tested our telescope in many multifrequency campaigns and it has clearly shown to be an important instrument in the future mw-campaigns on blazars. [ABSTRACT FROM AUTHOR]

This work describes an information system based on Web technologies which informs about Canary Island' passenger public transport. The main difference of this system with most existent on Internet is its inter-modal and integrator nature. [ABSTRACT FROM AUTHOR]