Understanding climate risks to world cultural heritage: a systematic analysis and assessment framework for the case of Spain

Abstract

Understanding the spatial distribution of world cultural heritage in its present-day geographical context is the foundation for the identification of and subsequent protection from key threats and vulnerabilities, particularly those arising from anthropogenic climate change. To address this challenge, we classified 45 Spanish world cultural heritage sites (WCHS) listed in the UNESCO register (as of 2023) according to type, entry date, and creation date. To establish a basis for a detailed analysis of the specific impact of climate change on the Spanish WCHS, a spatial cartographic database was developed showing the relationships between the WCHS and key geographical and climatic variables. We then used historical climate data, combined with a review of the impact mechanism of climate conditions on cultural heritage, to quantitatively evaluate the extent to which the WCHS in Spain are affected by local climate conditions from five aspects: freeze thaw cycle, thermal stress (thermoclastism), hydrodynamic scoring, corrosion, and biodegradation. Based on the above climate condition risks, we identified the five Spanish WCHS with the greatest potential climate condition risks, including Santiago de Compostela (Old Town), Pyrénées—Mont Perdu, the Roman Walls of Lugo, the Routes of Santiago de Compostela: Camino Francés and Routes of Northern Spain, and the Tower of Hercules. Additionally, based on different shared socioeconomic pathways (SSPs), we conducted a qualitative assessment of climate risk changes for WCHS in Spain under climate change. We found that the SSP1-2.6 scenario had the lowest climate risk, emphasizing the importance of achieving carbon neutrality for the protection of the WCHS. Our work translates historical climate conditions into specific climate risk levels for cultural heritage, providing data and theoretical support for effectively assessing the climate risks to Spanish WCHS.