Islands are among the most climate-sensitive regions globally, facing significant risks such as sea-level rise, tropical and extratropical cyclones, increasing temperatures, and changing rainfall patterns. However, current global climate models (GCMs) are not able to properly represent the small-scale processes crucial for islands due to their coarse resolution, such as, land-sea breeze, interaction of the flow with local complex and high orography, strong convection and winds. This is problematic for islands, especially those with complex topography and rich biodiversity, which also have fragile economies heavily dependent on climate-sensitive sectors like tourism and agriculture.
Macaronesia, a region in the North Atlantic comprising the Azores, Madeira, and Canary Islands, is the focus of the proposed study. Cape Verde, another archipelago in Macaronesia, is initially excluded due to insufficient observational data.
The Azores (236,000 residents) consist of nine islands (17–746 km²), with peaks up to 2351 m. Madeira (250,000 residents) includes two main islands (largest 741 km²), and two groups of two uninhabited islands each, and a peak at 1862 m. The Canary Islands (2.2 million residents) have eight islands (29–2034 km²) and a highest peak of 3715 m.
In each of the three archipelagos, climate is highly variable and strongly influenced by topography. Their different locations, between 27.5ºN and 40ºN, cause the synoptic conditions to be different, with the Azores being the rainiest archipelago. Also, westernmost islands, like the Azores, are less influenced by the proximity of the African continent and more exposed to maritime air masses. All three have a clear annual cycle with more abundant rainfall during the autumn and winter months. Furthermore, as they are small islands, and unlike other regions studied in previous FPS, heavy convective rains are not frequent in summer.
The main objective of this study is to investigate the processes affecting different climatic variables in Macaronesia at different spatial and temporal scales, with a particular focus on extreme events and their potential impacts. The set of variables studied is defined by the needs of the final stakeholders and their application to specific adaptation studies.
For this purpose, the use of different dynamical models (RCMs), ESD (empirical-statistical downscaling) and
hybrid techniques (emulators) are proposed, creating a coordinated downscaling approach. RCMs will be run at different resolutions to assess the added value of convection-permitting (CP) simulations compared to standard-resolution RCM. These simulations will be carried out by scientific groups of different countries, including some from the archipelagos.
The met services, AEMet and IPMA, included as partners, will provide access to observations and derived products. A few uncoordinated CP simulations exist over the area and will be used during the initial development phase.
The results of this study will be valuable for Vulnerability, Impacts, and Adaptation (VIA) communities, as the governments of the three archipelagos have expressed the need for high-resolution data that current GCMs and CORDEX RCMs cannot provide.
