A number of organizations are dedicated to this premise. A partnership between the Cities Alliance, the World Bank, UN-HABITAT and the United Nations Environment Programme (UNEP) works globally to help cities address climate challenges through sustainable urban development. Another organization, called C40, is a network of mayors of nearly 100 cities around the world whose mission is to halve the emissions of its member cities within a decade while improving equity and building resilience. C40 cities earn their place through action—with membership based on performance requirements, not member fees.
Led by the city of Oslo, C40’s Clean Construction Forum helps cities working to achieve zero embodied emissions from buildings and infrastructure by 2050. They focus on reducing emissions from construction materials and machinery by:
- Understanding the methods and data needed to establish city wide targets;
- Collaborating on available standards and tools to assess the environmental impact of materials and construction sites, and;
- Using cities’ collective power to develop a market for low emission construction materials and construction equipment.
Cutting emissions will require a change in business as usual. According to UN News, “The extraction and manufacturing of materials for buildings such as steel and concrete and construction processes produce carbon dioxide[,] so using low carbon infrastructure will also slash emissions.”
In addition to reduced emissions, cities built from bio-based materials such as timber that store carbon during their service lives can serve as constructed carbon sinks. They could increase the existing carbon pool of urban areas (1–12 GtC) by 25 to 170%.”