The citizen’s carbon footprint is affected by various factors, but mostly by electricity consumption, daily transportation, travelling habits, as well as municipal solid waste management, a critical factor that is not frequently incorporated in carbon footprint estimations. This paper proposes a new carbon footprint calculator, the Carbon Footprint Simulation Dashboard—COMPAIR’s CO₂ calculator. The CO₂ calculator employs Citizen Science (CS) information in order to assist citizens in understanding and comparing how future carbon emissions will be modified in accordance with changes in their daily routines. The calculator offers several statistics, e.g., the country’s average carbon footprint and comparisons between EU members with respect to sectors that shape it, along with several recommendations for those domains where carbon footprint is significantly higher than the desired limits. The novelty of this tool is the integration of waste management strategies as a dimension of the total CO₂ calculation. In this framework, the study presents the development of the Carbon Footprint Simulation Dashboard while two different waste management scenarios are applied with different citizen behaviours on recycling and composting. The applications highlighted the consumption in buildings that account for almost 50% of the total CO₂ emissions, while the crucial role of transportation is also a key parameter. The different waste management scenarios showed a correlation between the CO₂ footprint and the overall consumption/disposal habits of citizens. In the case of advanced recycling and composting, waste management accounted for up to 7% of the CO₂ emissions, and this highlights the significance of behavioural choices.

In the era of smart cities and digital transformation, ensuring digital inclusion has become a critical factor in fostering social cohesion and equitable urban development. While digital technology brings unprecedented opportunities for development, education, and civic engagement, barriers such as limited infrastructure, financial constraints, digital literacy gaps, and social exclusion continue to hinder full digital inclusion. This article explores the complex challenges of the digital divide and its impact on marginalized groups, including older adults, low-income households, migrants, and rural communities. Through a critical review of literature and policy analysis, this study examines key obstacles to digital inclusion in smart cities and evaluates the European Union’s response to these challenges through policy interventions, broadband expansion, digital skills programs, accessibility standards, and affordability measures. Additionally, the paper highlights strategies to enhance digital participation, such as citizen engagement, inclusive urban planning, and public-private partnerships. Through the analysis of EU initiatives and emerging policy approaches, this research contributes to the discourse on digital equity and provides insights into building smart, sustainable, and inclusive urban environments. The findings emphasize the need for integrated, cross-sectoral strategies to bridge the digital divide, ensuring that all citizens can access and benefit from the digital economy and society.

Citizen science (CS) initiatives have gained prominence as a powerful tool for advancing sustainability in urban environments. This paper delves into the role of CS in facilitating policymaking and promoting behavioral change for long-term sustainability goals. By actively involving citizens in scientific research and data collection, CS projects offer a unique opportunity to harness the collective intelligence and resources of communities. These initiatives not only generate valuable data on environmental quality, biodiversity, and human behaviors but also promote public awareness, education, and civic engagement. Moreover, CS has the potential to influence policy-making processes by providing policymakers with evidence-based insights and fostering collaboration between scientists, industry stakeholders, policymakers, and most importantly citizens. The paper presents a comprehensive review of 83 European-funded CS projects specifically tailored to urban contexts. These projects address a wide range of sustainability challenges, including climate change, environmental monitoring, public health, urban planning, and sustainable energy. The analysis highlights key factors that contribute to the success of CS projects, such as clear goals, well-designed communication strategies, robust community engagement, and the effective use of digital technologies. It emphasizes the importance of collaboration among various stakeholders, including citizens, researchers, policymakers, and practitioners, to maximize the impact of CS in achieving sustainable development goals. It also calls for increased policy support, enhanced inclusivity and diversity in CS initiatives, and the adoption of a holistic research approach to further advance the field. In conclusion, citizen science emerges as a transformative force for driving sustainable development and behavioral change in urban environments. By empowering citizens to actively contribute to scientific inquiry and decision-making, CS initiatives can bridge the gap between science and society, fostering informed decision-making, collective action, and a more sustainable future for cities.