New CORDEX Flagship Pilot Study on Island processes in the Macaronesian Archipelagos (FPS-I-Mac): Objectives and challenges

Small islands, particularly those with complex topography and fragile economies reliant on climate-sensitive sectors like tourism and agriculture, are highly vulnerable to climate change. Challenges such as rising sea levels, tropical and extratropical cyclones, increasing temperatures, and shifting rainfall patterns significantly affect these territories. However, current global climate models (GCMs) lack the resolution needed to capture critical local processes essential for these regions. The “FPS on Macaronesian Archipelagos. Convection Permitting projections focused on island processes (FPS-I-Mac)” is a Flagship Pilot Study (FPS) initiative focuses on Macaronesia, an Atlantic region comprising the Azores, Madeira, Cape Verde, and the Canary Islands archipelagos.

Each archipelago exhibits unique climatic characteristics, influenced by its topography and geographical location. For instance, the Azores are the rainiest, while the Canary Islands are more influenced by continental air masses. All four archipelagos experience distinct annual cycles, with heavier rainfall during autumn and winter. Unlike other regions, intense summer convective rain is uncommon.

This communication presents the main objectives and challenges of this FPS: 

• Investigate multiscale climatic processes and their interactions to improve climate projections in Macaronesia.
• Assess the influence of sea surface temperature (SST) and aerosols in these oceanic regions.
• Compare high-resolution simulations with standard-resolution models to evaluate their added value in extreme event analysis.
• Create a shared database and produce ensembles of climate projections generated by different dynamical techniques (as models, empirical-statistical downscaling, hybrid techniques as emulators) tailored for Vulnerability, Impacts, and Adaptation (VIA) communities.
• Foster collaboration between scientific communities and end-users.

Expected Impact are, between others: 

• Enhanced understanding and modeling of climate in islands with complex topographies.
• Reduction of uncertainties in 21st-century climate projections for the Macaronesian region.
• Provision of accurate data for key sectors such as agriculture, health, energy meteorology, and risk management.
• Strengthened synergies among stakeholders, promoting a fair ecological transition in these vulnerable regions.

The FPS aligns with CORDEX objectives by improving regional climate projections for small islands, which are underexplored in current studies. We will use different regional climate models (RCMs) at convection-permitting resolution, but also empirical-statistical downscaling (ESD), and hybrid strategies for high-resolution simulations, enabling detailed analysis of extreme events. Local and satellite observations associated with reanalysis products will validate these processes. By contributing to global discussions and integrating end-user needs from the outset, this initiative will support both local decision-making and broader climate research in the area during the next 5 years. The current team includes research groups from Portugal, Switzerland, Italy, and Spain, but it is open to new participants in different topics.