Circular economy (CE) is a recently introduced concept by the EU and several national governments that aims to reduce the total resources extracted from the environment and limit waste generated by human activities to achieve human well-being and sustainability. This review aims to bring awareness of heritage sites’ role and significance in reducing carbon footprints as a strategy for applying CE and promoting sustainable urban development. This study adopts a qualitative content analysis methodology, selecting academic literature, international case studies, and policy documents based on their relevance to CE principles and heritage conservation. The approach examines the emergence and dissemination of these concepts through published literature, including professional standards and guidelines for valuing and managing heritage sites. Key themes include adaptive re-use strategies, preventive conservation, and policy integration. A comparative reflection on international case studies was conducted to highlight trends, regional variations, and challenges. This review concludes by identifying research gaps and proposing future directions, reinforcing the value of heritage sites as pivotal assets in advancing CE frameworks. This structured synthesis provides a theoretical and practical contribution to integrating circular economy strategies in heritage conservation.

Understanding the formation and spatiotemporal distribution of particulate matter (PM) is crucial in atmospheric science and air quality assessment (Omari et al., 2019). PM comprises a mix of organic and inorganic particles suspended in the air, categorized by aerodynamic diameter into PM₁₀ (2.5–10 μm) and PM_2.5 (<2.5 μm), with the latter largely derived from gaseous precursors (Abuelgasim and Farahat, 2020; Abuelgasim et al., 2021). This study analyses the distribution of air pollutants in the Emirate of Abu Dhabi using hourly data from air quality stations to assess concentrations of PM₁₀, PM_2.5, and other gases such as NO₂ , CO, SO₂ , and O₃ . Spatial maps and statistical analyses reveal that PM concentrations follow a seasonal cycle, peaking in summer due to natural dust events and declining in winter. Maximum PM₁₀ and PM_2.5 values reached 218 μg/m³ and 60 μg/m³ in summer, and 169 μg/m³ and 34 μg/m³ in winter, respectively. The PM_2.5 / PM₁₀ ratio was generally below 0.5, indicative of dominant natural sources typical of arid environments (Abuelgasim and Farahat, 2020). Results suggest that the primary drivers of pollution are desert dust and transboundary transport, with limited influence from local anthropogenic sources. While this study focuses on inland areas, future research will address coastal zones where sea salt aerosols and human activities, including marine transport and urbanization, may contribute significantly to air pollution.