The number of people who live in cities—already a majority of the world’s population—is expected to rise more than 50% by 2050 to 6.5 billion.
As people move to cities and urban populations grow, so does the demand for services such as electricity, transportation, and waste removal—often high-emitting industries. Growing cities can also encroach on the surrounding landscape: new construction often destroys forests and wetlands that remove greenhouse gas (GHG) emissions from the atmosphere or coastal ecosystems that provide protection from storms or floods. These changes increase urban-area GHG emissions and decrease resilience to the risks associated with climate change.
Because the fastest urban growth is expected to happen in developing countries, such cities’ per capita emissions could skyrocket—and their most vulnerable communities will be increasingly threatened by climate impacts such as floods, extreme heat, and sea level rise.
In our new paper, we argue that net-zero strategies are key to managing GHG emissions in cities. But these strategies need to be part of a wider and more integrated urban planning approach that serves multiple objectives including climate change mitigation and adaptation, pollution reduction, effective governance, and local livelihoods. Rather than solely focusing on GHG and energy issues as past net-zero strategies have, green-city strategies must also focus on meeting citizens’ pressing needs for clean air, water, equity, and jobs, to enable cities to grow their economies while reducing GHG emissions.
An integrated green-cities planning approach should produce environmental, social, and economic benefits for all residents.
The paper outlines three lessons learned that governments and organizations should take into consideration for sustainable urban development:
1. Take a multi-sector integrated approach
Designing green-city strategies starts with modeling potential pathways that achieve the desired objectives, from reducing GHG emissions to increasing green jobs. For New York City, we used our CO2Sight analytics platform to quantify pathways to achieve the city’s carbon neutrality goal. CO2Sight can be replicated for any city thanks to its ability to use multiple kinds of modeling tools, diverse datasets, and customized assumptions in an integrated framework. CO2Sight is the basis for our green-cities planning framework, which expands the platform to include more sectors, strategies, and outcomes, with added flexibility to accommodate additional tools and data sources.
2. Use an inclusive, bottom-up planning process
Creating more resilient urban areas requires an inclusive, integrated approach— particularly in the aftermath of a natural disaster. In earthquake-ravaged Nepal, we worked with municipal leaders in a multi-level stakeholder process to find the solutions that work best for local communities. One outcome, codifying resilient building construction techniques at the community level, helped seven of the largest urban centers outside the Kathmandu valley rebuild infrastructure more equitably.
3. Apply an integrated analytics framework to deliver lasting benefits
Successful green-city strategies must be financially viable and promote economic development. In Ghana, we worked with the U.S. Agency for International Development to plan for the country’s growing electricity sector. Using an inclusive stakeholder process and an integrated analytics platform, we identified opportunities for power system expansion—at a cost of $300 million less than previously estimated—while delivering a greener grid that supports low-emission sustainable development.
City planners and their counterpart leaders at municipal, regional, and national levels are preparing for new waves of urban development. They should focus on integrated multisector solutions that deliver local benefits to all citizens through cleaner air, water, and streets—and, ultimately, healthier lives. Investing in more resilient urban systems and services in this way also offers the greatest potential for increasing equity and inclusiveness.
To meet cities emerging challenges—to incorporate rapid population growth, rising demand for energy and other services, and growing inequality—urban leaders will need to change their current approaches to planning and decision-making. But such changes can be enormously beneficial to improving citizens’ lives while meeting climate and other goals. The first step on that path is to establish a multi-sector, multi-function integrated approach that balances climate mitigation and risk management with pressing needs for cleaner air and water, better access to services, and inclusive green jobs.
Read our recently released paper for guidance on actionable strategies to promote sustainable urban development.