Urbanization is the path that lies ahead. Currently, our planet is home to roughly 8 billion individuals. However, projections indicate that by 2050, the global population will soar to nine billion, with a staggering 70 percent residing in urban areas. As we move forward, cities will absorb 90 percent of population growth, they will be responsible for 80 percent of enhanced prosperity, but also for approximately 75 percent of energy consumption and they emit about 60 per cent of the world’s total greenhouse gases. These urban conurbations will assume pivotal roles as hubs of political, economic, and cultural activities. They will serve as living testaments of the future, shaping the lifestyles and work environments for generations to come.
Impact and Implications of Urban Resilience
The concept of a resilient city has emerged as a response to the challenges of global change, focusing on the ability of urban areas to withstand and recover from shocks and stresses while ensuring the well-being of its residents. Key characteristics of resilient cities include adaptability, diversity, collaboration and engagement, risk management, sustainability, and social equity. Resilient cities prioritize flexible urban planning, promote diverse economies and social structures, foster collaboration among stakeholders, prioritize risk assessment and mitigation, emphasize sustainable practices, and address social vulnerabilities. Hence, resilient cities are designed to minimize the impact of disruptive events such as climate change, natural disasters, economic downturns, and social crises.
The rise of resilient cities presents numerous opportunities for science and industries to contribute to the development of a livable urban future. Key sectors to support are urban planning and design, infrastructure development, information technology and data analytics, renewable energy and clean technologies, water management and conservation, emergency management and disaster response, sustainable transportation and mobility, and social services and community development.
With the ongoing digital transformation of our society, enormous amounts of data are collected daily on nearly every aspect of our lives, land use, and the environment. This digitalization offers significant potential for identifying opportunities and risks, in particular with respect to urban resilience. Therefore, data has become one of the most coveted resources in resilient cities concepts worldwide. But how can the ever-growing treasure trove of data be used effectively for shaping livable and future-proof cities? This is where Earth Observation (EO) comes in.
Monitoring Cities from Space
Urban resilience is influenced and challenged by local to global factors and various drivers. To identify and better understand these factors and drivers, a global – or at least spatially comprehensive – perspective is necessary. Here, EO can make a valuable contribution. Geo-information derived from satellite imagery provides an up-to-date, spatially consistent, and at the same time detailed picture of the natural, cultivated and built environment and their dynamics. What are the current regions experiencing rapid urban growth? Have new settlements been established in areas vulnerable to hazards? And what is the population at risk in such instances?
To help answering these questions, applied research in the EO sector increasingly focusses on thesynergistic use of big Earth data, effective data analytics, modern information and communication technologies (ICT), and instruments of open and shared knowledge. The data and information derived from EO imagery and tools can serve as a basis for the dialogue in the global change context and for the implementation of indicator-based environmental observation systems and evidence-based decision support with respect to the implementation of resilient cities.
In this context, applicable information derived from multi-sensor EO data feeds a wide variety of applications: At the global level, geoinformation on the settlement pattern, impervious surfaces, vegetation or air pollution have been developed and changes over time can be monitored. On a regional or local level, there is very high-resolution geo-information has been produced on tree stands and green roofs, effects of urban greening, urban heat islands, the number of solar panels or, in the context of natural hazards, on exposed areas of flooding or landslide hazards, among many others. EO-based geoinformation has also effectively been coupled with other sources such as census data, social media, volunteered geographical information, and citizen science to spatially analyze exposed populations or attitudes of people.
Key technical components for the applications and activities outlined afore include the automated extraction of information from extensive and diverse datasets. These datasets include various sources such as public surveying and administration on the one hand and satellite-based Earth observation such as facilitated by the European Commission’s Copernicus program and contributions from private sector companies and emerging space start-ups. Moreover, machine learning and artificial intelligence techniques are employed in combination with powerful computer clusters to enable high-performance processing and data analytics for effective information extraction. Here, modern information and communication technologies play a vital role in enabling automated control over data access, management, and processing. These technologies facilitate analytics-ready data, end-to-end solutions, sharing, and the utilization of platform economies. They incorporate mechanisms for data access and management, such as Open Geospatial Consortium (OGC) web services, along with support for implementing operational service chains, including orchestration and processing. Additionally, efforts are made to contribute solutions for cross-platform services and standards, exemplified by the OpenEO Application Programming Interface, thereby fostering interoperability and compatibility across different platforms.
Future Directions of Research and Development
To effectively leverage the vast amounts of data generated in our digitized society, future EO research and development (R&D) should increasingly aim at creating a transdisciplinary nexus between spaceborne Earth observation, digital administration and society, and decision makers in planning, business, science, and politics. By harnessing the power of big data, advanced analytics, and modern ICT, future EO R&D can help to create tailored information for new digital products and business models, promoting the exploration of new markets and providing evidence-based policy advice. In particular, the integration of different actors and sectors within a common ecosystem and the standardized exchange of data and functionalities will significantly contribute to improve strategies and instruments such as the United Nations' Urban Agenda and Sustainable Development Goals (SGD), World Bank’s Resilient Cities program, the development programs of the African Development Bank and Asian Development Bank, or the European Green Deal.
The concept of resilient cities is a response to the challenges posed by rapid urbanization, climate change, inequalities, and technological disruptions. Building resilience requires collaboration among stakeholders, innovative approaches to urban planning, and the integration of sustainable practices. Various industries have the opportunity to contribute to the development of resilient cities, while Earth Observation allows to harness the power of data and technology to support the creation of new knowledge as basis for developing sustainable and resilient urban environments.