Vulnerability of Coastal Heritage in the Context of Climate Adaptation: A Review ^†

Abstract

Mediterranean coastal heritage sites face escalating threats from climate change, including sea-level rise, coastal erosion, and extreme weather events. These risks endanger both the physical preservation of archeological sites and thei socio-economic significance/contribution. This review evaluates advanced tools such as Geographic Information Systems (GISs), remote sensing, and flood modeling for assessing vulnerabilities and supporting adaptive conservation strategies. Significant research disparities among Mediterranean regions are identified, underscoring the need for equitable and collaborative frameworks. The findings emphasize the integration of innovative technologies with sustainable practices to safeguard cultural heritage, ensuring resilience against climate-induced risks and contributing to long-term conservation goals.

1. Introduction

Cultural heritage sites, including archeological remains, historic monuments, and cultural landscapes, are invaluable repositories of human history, offering profound insights into past civilizations and serving as critical resources for education, tourism, and cultural identity [1,2,3]. However, these sites face increasing threats from natural and anthropogenic pressures, with climate change emerging as a significant factor exacerbating their vulnerability. Changes in temperature, precipitation, and sea-level rise (SLR) patterns are already affecting the physical environment of cultural heritage, while extreme weather events like storms and marine floods pose acute risks [2,4,5].

Furthermore, the dynamic nature of coastal zones introduces additional challenges. Coastal archeological sites are particularly vulnerable to the erosion, saltwater intrusion, and sediment displacement, commonly associated with human interventions such as over-pumping, seawalls, and other hard infrastructures. While structures may provide localized protection, they frequently lead to unintended consequences, including increased erosion in adjacent areas [6,7,8,9].

Among the most susceptible regions, the Mediterranean region stands out due to its unique cultural and historical significance, often regarded as the ‘cradle of civilization’ [10]. This region hosts 159 UNESCO World Heritage Sites along its coasts, many of which are threatened by SLR, and coastal erosion, while the frequency of extreme storms is increasing [11,12]. Recent projections indicate that, under RCP 8.5, climate-induced coastal flooding in Europe could lead to a tenfold increase in economic losses by 2070, with damage surpassing €209.8 billion annually [13]. The risks posed by these environmental changes are not merely theoretical but are already evident in several high-risk locations. For example, Delos Island in Greece is characterized as a high-risk site in the Mediterranean basin, where coastal retreat driven by relative SLR is already evident [14]. These hazards not only threaten the physical integrity of heritage sites but also disrupt their broader cultural, social, and economic functions.

In particular, rising seas contribute to more frequent flooding, structural damage, and the potential loss of irreplaceable historical information [15,16,17]. Such findings highlight the urgent need for adaptive management strategies to mitigate financial and structural risks. Without effective interventions, the economic burden on Mediterranean heritage sites is projected to rise significantly. For instance, the accumulated damages from inaction in Mediterranean coastal cities such as Barcelona and Valencia could surpass €50.4 billion by 2100 [18]. Additionally, the absence of adaptive investment could see Expected Annual Damage (EAD) across Europe’s coastal regions exceed €209.8 billion by the end of the century [13].

In contrast, targeted adaptation investments, including flood protection and sustainable tourism integration, could reduce potential losses by up to 98% [18]. Understanding these economic risks requires a comprehensive and geographically balanced research approach. However, the distribution of existing studies on coastal heritage vulnerability is uneven across the Mediterranean.

The effective conservation of these sites requires an integrated approach that combines innovative technologies with sustainable management practices. Advanced methodologies such as Geographic Information Systems (GISs), remote sensing, and marine flood modeling have proven instrumental in assessing vulnerabilities and developing adaptive strategies. These tools enable systematic monitoring, vulnerability mapping, and predictive modeling, which are critical for informed decision-making and long-term conservation planning [8,19].

This review aims to evaluate the vulnerability of Mediterranean coastal heritage sites to climate change impacts, focusing on key risks such as sea-level rise, coastal erosion, and extreme weather events. It synthesizes findings from recent studies to highlight disparities in research coverage across regions, identifies innovative methodologies like GIS and remote sensing for risk assessment, and emphasizes the integration of sustainable tourism and adaptive management strategies. By addressing knowledge gaps and proposing actionable recommendations, the study seeks to support the development of holistic frameworks that ensure the preservation and resilience of these cultural treasures amidst growing environmental challenges.

2. Methodology

This study conducted a systematic review focused on the Mediterranean, using the PRISMA 2020 guidelines [20] and VOSviewer software (version 1.6.19) to ensure a precise and replicable process for identifying and analyzing the relevant literature. The PRISMA methodology streamlined the refinement of studies, guaranteeing the inclusion of only high-quality research in the final analysis [21,22].

The framework (Figure 1) illustrates the research structure, detailing the process of study selection and exclusion. An initial database search identified 1,200 records. After removing 153 duplicates, 1,047 unique records remained for screening [23]. Titles and abstracts were reviewed, excluding 698 records as irrelevant to the study’s scope, narrowing the selection to 349 articles for full-text assessment. Specific limitations were applied during the study selection process to ensure relevance and focus. Publications were restricted to the period from 2014 to 2024 to reflect recent advancements and trends, and only articles published in English were included. Priority was given to peer-reviewed journal articles and conference proceedings, while book chapters and theses were excluded. Articles outside the Mediterranean geographic scope, lacking full-text access, or deemed thematically irrelevant were also removed during the eligibility assessment.

At the full-text assessment stage, 299 articles were excluded for reasons such as classification as book chapters or theses (n = 26), publication outside the specified date range (n = 17), non-English language (n = 9), lack of full-text access (n = 23), thematic irrelevance (n = 112), or focus outside the Mediterranean (n = 31). Of the remaining 131 articles, a detailed eligibility review excluded a further 81 articles for similar reasons: book chapters or theses (n = 7), non-English language (n = 2), and off-topic studies (n = 72). Ultimately, 50 studies met all inclusion criteria and were selected for this review.

The literature search was conducted using three major databases: Scopus, Web of Science, and Google Scholar, selected for their comprehensive academic content and the inclusion of peer-reviewed studies. Boolean operators were used to combine predefined keywords, including (i) Mediterranean, (ii) Coastal Heritage Sites, (iii) Coastal Archaeological Sites, (iv) Climate Change, (v) Sea Level Rise, (vi) Coastal Vulnerability, (vii) Climate Adaptation, (viii) Sustainable Tourism, (ix) GIS, and (x) Risk Assessment. These keywords, detailed in

Table 1. Keyword Combinations Used in the Literature Search.

Primary Theme	Keyword Combinations
Climate Change Impacts	“Mediterranean” AND (“Climate Change” OR “Sea Level Rise” OR “Coastal Vulnerability”)
Heritage Sites	“Mediterranean” AND (“Coastal Heritage Sites” OR “Coastal archaeological sites”)
Adaptation Strategies	“Mediterranean” AND (“Adaptation strategies” OR “Climate adaptation measures”)
Tourism	“Mediterranean” AND “tourism” AND “coastal area”
Sustainable Management	“Mediterranean” AND (“Coastal management strategies” OR “Integrated coastal zone management”)
Technological Tools	“Mediterranean” AND (“GIS” OR “remote sensing” OR “3D photogrammetry” OR “risk assessment”) AND “Heritage Sites”
Environmental Risks	“Mediterranean” AND (“coastal erosion” OR “flooding” OR “risk assessment”)
Ecosystem Services	“Mediterranean” AND (“ecosystem services” OR “coastal ecosystem management”)

, guided the systematic retrieval of studies relevant to the research questions. This structured approach ensured the identification of high-quality studies, refining the selection to focus on the literature that directly addresses the specified themes. The process minimized irrelevant results while maintaining comprehensive coverage of the research scope.

In addition to the literature screening, VOSviewer software (version 1.6.19) was employed to conduct bibliometric analysis, generating graphs that visualize relationships between documents, including citation patterns and keyword co-occurrence networks.

This allowed for a comprehensive examination of collaboration networks and thematic trends within the selected literature.

3. Findings

The systematic review of 50 articles assessed the vulnerability of coastal heritage sites in the Mediterranean region to the impacts of climate change, focusing on sea-level rise, coastal erosion, and extreme weather events. The reviewed studies highlight the increasing threats to these valuable sites and the urgent need for adaptive management strategies.

3.1. Geographical Distribution of Studies

The systematic review highlighted that most studies on coastal cultural heritage in the Mediterranean region are concentrated in Tunisia, Italy, and Spain, accounting for almost 50% of the articles reviewed. Other notable countries include Greece, Libya, and Turkey, which also receive significant attention. A total of 17 countries were represented in the studies reviewed, with Tunisia leading the field with about 20% of all studies conducted, followed by Italy and Spain (Figure 2). Countries such as France, Cyprus, Israel, and Albania are under-represented in the reviewed studies, reflecting a disparity in research focus across the Mediterranean region.

3.2. Research Methodologies

A variety of methodologies have been utilized in coastal heritage research, reflecting the multifaceted challenges posed by climate change. These methodologies are separated into two different categories, a) software approaches, which provide analytical and predictive capabilities, and b) hardware approaches, which enable real-time monitoring and site-specific interventions. Among the software approaches, remote sensing analysis is the most widely used technique, accounting for 35% of the reviewed studies. This method leverages satellite and aerial imagery to monitor shoreline dynamics and assess coastal erosion. Geographic Information Systems (GISs), utilized in 25% of cases, are equally pivotal, enabling spatial analysis, vulnerability mapping, and the creation of risk models to support informed decision-making. Flood modeling, implemented in 15% of studies, offers critical insights into the projected impacts of sea-level rise and extreme weather on cultural heritage sites. Additionally, photogrammetry (10%) and LiDAR are increasingly applied for precise archeological documentation and 3D modeling, providing detailed assessments of structural integrity. Finally, historical data analysis and satellite imagery analysis (5% each) contribute valuable long-term perspectives on changes in environmental conditions and site-specific vulnerabilities. On the other hand, hardware approaches focus on practical tools for immediate and localized data collection. Drones (3%) have become indispensable for high-resolution imaging and real-time surveys, particularly in remote or vulnerable coastal areas. Similarly, environmental sensors (2%), including tide gauges and ground-penetrating radar, provide essential information on site stability and environmental changes.

These methodologies, while distinct in their applications, are not mutually exclusive. The integration of software and hardware approaches offers a comprehensive approach to addressing the risks faced by coastal heritage sites. Software approaches enable large-scale analysis and predictive modeling, while hardware measures provide the on-the-ground insights needed for timely interventions. As illustrated in Figure 3, remote sensing analysis and GIS dominate as primary methodologies, while flood modeling, photogrammetry, and drones complement the technological toolkit. This balanced use of tools highlights the field’s commitment to leveraging innovation to safeguard cultural heritage under the growing threats of climate change.

3.3. Research Themes, Trends, and Keyword Analysis

Several studies analyze climate change—particularly SLR and coastal processes—which has become a critical point in recent research on coastal heritage regarding environmental threats. A significant part of the literature focuses on vulnerability assessments tied to adaptation strategies, aiming to identify effective measures for risk mitigation. Emerging keywords such as “coastal cultural heritage,” “climate change,” “sea-level rise,” and “risk assessment” reveal substantial growth in recent publications, reflecting heightened awareness of the challenges posed by climate change. Figure 4a illustrates the keyword network, and the inter-connectedness of these keywords emphasizes how adaptation strategies, archeological site monitoring, and risk evaluation are becoming interdependent areas of research. The temporal overlay (Figure 4b) provides additional insights into the evolution of research priorities over time. Recent years, particularly after 2019, have seen the emergence of terms like “adaptation,” “decision-making,” and “sea-level rise,” highlighting a shift toward proactive approaches in safeguarding vulnerable heritage sites. Concurrently, the keyword density visualizes the intensity of research focus across various terms, with areas like “cultural heritage,” “climate change,” and “risk assessment” showing high concentrations. Emerging themes, such as “adaptation strategies” and “GIS,” further demonstrate the growing integration of technical methodologies and policy frameworks, like Integrated Coastal Zone Management (ICZM), into conservation efforts.

The trends reflected in these visualizations illustrate how coastal cultural heritage is no longer studied in isolation but as part of broader frameworks addressing climate resilience and sustainable management.

3.4. Temporal Trends and Research Growth

The analysis of publication trends shows a significant increase in studies from 2020 onward, reflecting the growing recognition of the need to protect cultural heritage from climate-related hazards. As illustrated in Figure 5, the number of publications per year shows a steady rise, spiking in 2023 and 2024. Additionally, the rise in publications may be attributed to the adoption of advanced technologies and innovative methodologies, which have enhanced research capacities and broadened the scope of studies in recent years.

4. Discussion of Key Findings

Based on the 50 articles reviewed, the findings indicate a strong focus on assessing risks to coastal cultural heritage from environmental hazards such as flooding, erosion, and rising sea levels. These risks have been well-documented, with rising sea levels posing a significant threat to archeological sites due to inundation, saltwater intrusion, and changes in storm surge intensity [2,4,24]. The methodologies employed primarily rely on remote sensing technologies, GIS-based spatial analysis, and flood modeling, showcasing the growing trend toward leveraging technological innovations in understanding and mitigating these risks [16,25]. This technological shift has enabled researchers to conduct large-scale vulnerability assessments, particularly in regions with well-documented heritage assets and significant climate exposure. As a result, countries such as Tunisia, Italy, and Spain have been at the forefront of such research, likely due to their extensive cultural heritage in coastal regions and heightened exposure to climate risks.

Heritage tourism remains a crucial parameter of the Mediterranean economy, with historic sites attracting millions of visitors annually and supporting thousands of jobs [12]. However, increasing climate-induced damage threatens this economic engine. Rising sea levels, increased storm intensity, and coastal erosion have already begun to impact major heritage sites, leading to disruptions in tourism revenue and local economies.

These factors compound existing challenges, placing further pressure on conservation budgets. Given the scale of the projected economic and structural risks, adaptation strategies must be prioritized to prevent irreversible damage. Addressing these challenges requires integrating scientific risk assessments with proactive planning approaches. A key emerging theme in the literature is the integration of risk assessments with adaptation planning, emphasizing the importance of preserving the outstanding universal value (OUV) of these sites. The reviewed studies highlight the need for region-specific strategies and localized interventions to protect these sites from the ongoing threats posed by climate change [19,26,27]. Finally, the keyword analysis reveals that while climate change and SLR dominate the discussion, there is growing interest in methodologies for adaptation and conservation of coastal heritage. These findings suggest the need for comprehensive, regionally tailored strategies that emphasize early action and sustainable practices to safeguard coastal cultural heritage effectively.

5. Conclusions

Mediterranean coastal heritage sites stand at the intersection of cultural importance and environmental vulnerability. This review highlights the serious threats caused by climate change, including sea level rise, coastal erosion, and extreme weather events, which place both the structural integrity and socio-economic value of these irreplaceable assets at high risk. Addressing these challenges requires integrating adaptive conservation strategies with technological advancements such as GIS, remote sensing, and flood modeling, which enhance risk assessment and conservation efforts. While these tools have significantly advanced risk monitoring and enhanced decision-making, their application remains uneven across the Mediterranean due to disparities in funding, research capacity, and policy implementation.

Future efforts should focus on integrating emerging technologies, improving predictive modeling, and fostering adaptive management tailored to regional contexts [26]. Additionally, sustainable tourism offers untapped potential to generate revenue that can support conservation initiatives. Ensuring the success of these efforts will require collaboration among researchers, policymakers, and local communities to create strategies that are not only regionally relevant but also aligned with global conservation objectives. Furthermore, disparities in research focus across Mediterranean countries hinder comprehensive conservation efforts. Nations such as Tunisia, Italy, and Spain dominate the academic discourse due to their rich cultural heritage and active research communities.

This imbalance underscores the need for more equitable research and resource allocation to protect the region’s shared heritage. Under the RCP 8.5 scenario, Mediterranean coastal flood risks could increase exponentially, with projections estimating shoreline retreats between 34.1 and 81.2 m, particularly affecting high-risk areas such as the Nile Delta region [28]. In Greece, the case of Delos Island serves as an example of the tangible risks posed by rising sea levels, where ongoing erosion has already altered the coastal morphology of this UNESCO World Heritage Site [14]. These findings highlight the critical need for proactive, long-term adaptation planning to safeguard Mediterranean coastal heritage.

According to scientific assessments, coastal protection measures should align with the RCP 4.5 or RCP 6.5 scenarios, especially in high-risk areas requiring urgent intervention. Implementing strategies based on these emission scenarios facilitates the adoption of cost-effective and adaptive solutions that enhance the resilience of vulnerable coastal zones. By integrating climate projections into planning, decision-makers can develop sustainable protective measures that optimize financial resources while mitigating long-term risks.

Investing in nature-based solutions, such as wetland restoration, coastal buffer zones, and managed retreats, can minimize infrastructure damage and reduce future expenditures, making them a financially viable option for local communities. Additionally, a monitoring framework should assess the effectiveness of protective measures, allowing for strategy adjustments based on RCP 8.5 projections to address escalating climate risks.

Preserving Mediterranean coastal heritage requires a holistic approach that integrates cultural conservation and climate resilience, supported by international cooperation, interdisciplinary research, and policy-driven strategies. By enhancing research efforts, fostering innovation, and prioritizing sustainability, future initiatives can ensure that these cultural heritage sites remain protected, accessible, and meaningful for generations to come.