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The aim of this study is to evaluate the geomagnetically induced current (GIC) hazard in the power networks of the Canary and Balearic archipelagos. This is done in order to strictly complete the detailed assessment at national level of the power transmission system of mainland Spain, including the 400 and 220 kV levels. We have constructed models for the grids in each of the individual systems and used resistivity models of the lithosphere for each group of islands, from which we have calculated the surface impedances. The respective models of electrical admittances of the grids have been combined with the geoelectric field derived from the convolution of the recorded (or expected in an extreme scenario) geomagnetic storms and the impedances calculated from the geoelectrical models to derive the expected GICs in the power lines, substations, and transformers. The low geomagnetic latitude of the Canary Islands combined with the small size of their power networks, makes them one of the least likely electrified locations to record significant GICs, with less than 3 A for the 100‐year return period. Even the 13 A that could be reached for the upper limit of the 95% confidence interval at the 500‐year return period does not seem likely to have a significant impact. The Balearic Islands, being at higher latitude and with a system length of approximately 300 km, including alternating current power lines connecting the Islands, shows GIC signals of moderate amplitude with up to 40 A for the 100‐year return period. Plain Language Summary: In the same way that phenomena derived from meteorological processes can have devastating effects, the Sun emits massive amounts of particles and energy into space that affect Earth technological systems. The related science is analogically called space weather. When the Sun is active, it sends out more charged particles that can affect the regions around the Earth where those particles interact with the planet's magnetic field. This leads to a significant increase of electric currents in these media giving rise to geomagnetic storms. This generated electrical fields act like a voltage source and cause electrical currents to flow through the power networks, that can damage the transformers where the circuit is grounded. Many countries, such as Spain, have undertaken studies to assess the vulnerability of their power grids to the danger posed by this phenomenon, but one question that remained open was whether the grids that transmit power across their islands deserve attention. Our results show that the vulnerability of the Canary Islands is very low, while that of the Balearic Islands is not negligible. Key Points: We quantify the historical geomagnetically induced currents (GICs) and the worst‐case scenarios in the power grids of the Spanish IslandsCanary Islands is one of the least likely electrified locations in the world to record significant GICsThe Balearic Islands, with their higher latitude and long power lines connecting the islands between them, are more vulnerable to GIC [ABSTRACT FROM AUTHOR]

Volcanic areas create spectacular landscapes that contain a great diversity of geoheritage. The study of this geoheritage enables us to inventory, characterise, protect and manage its geodiversity. The Canary Islands are a group of subtropical active volcanic oceanic islands with a great variety of magma types and eruption dynamics that give rise to a wide diversity of volcanic features and processes. The aim of this paper is to identify, for the first time, the diversity of volcanic geoheritage of the Canary Islands and to appraise the protection thereof. To this end, a geomorphological classification is proposed, taking into account the features and processes directly related to volcanism, such as those resulting from erosion and sedimentary processes. The main findings demonstrate that the volcanic geoheritage of the Canary Islands is extremely varied and that this geodiversity is safeguarded by regional, national and, international protection and management frameworks. Even so, and given the enormous pressure of coastal tourism on the coastlines of the islands, we believe that continuing efforts should be made to conserve and manage their volcanic and non-volcanic geoheritage, so that these places can continue to be enjoyed in the form of geotourism. [ABSTRACT FROM AUTHOR]