This article from UNAI Member School New York University?is the second?in the UNAI START series that looks at Sustainable Development Goal #11:Sustainable Cities and Communities. Schools and departments of urbanization at UNAI member institutions were asked to submit articles highlighting research and work?relating to the design and construction of more resilient and sustainable cities for the 21st century, and?to showcase the importance of addressing urbanization?in achieving?the 2030 Development Agenda. Please note that the articles are for discussion, and do not necessarily reflect the views of the United Nations.

Hurricane Sandy, which ravaged the Caribbean Islands and the East Coast of the United States in October 2012, was the largest Atlantic hurricane on record. In a freak combination with other regional weather patterns, this super storm made landfall in a direct hit on the New Jersey Shore, bringing strong winds, torrential rain, and storm surges of more than 13 feet to the shores of that densely populated state and to the adjacent City of New York. ?The storm killed 114 people in New York and New Jersey, caused tens of billions of dollars in damage, crippled transportation networks, damaged or destroyed some 660,00 housing units, and knocked out power to over 4 million homes, in some cases for weeks and even months. Recovery and rebuilding efforts have ranged from immediate local responses by grassroots community groups to large-scale and ongoing regional planning efforts like the federal government Rebuild by Design competition. The recovery, like the storm&rsquos immediate impacts that preceded it, have varied greatly from community to community. As such, they have much to tell us about the social as well as infrastructural factors that make a difference in building cities that are more resilient to extreme weather events.

A sustainable city is not just a responsible steward of natural resources, it is prepared for the challenges of a changing climate. In a world of global climate change, extreme weather events like heat waves and hurricanes are likely to be increasingly common and severe. Coastal cities, which are growing across the globe, are under particular risk of rising sea levels and more destructive storms. They also present perhaps the most important opportunity to get it right as we plan and prepare. This is what we are working towards when we study and advocate for smart urban planning for climate change resilience.

Fundamentally, a resilient city is a city that can withstand and bounce back from disaster. Like sustainability, resilience is social as well as physical. ?In our work at the New York University Institute for Public Knowledge, we look at integrated regional systems and local public services, heavy physical infrastructure and community-based social infrastructure. New development that isn't resilience-minded is unsustainable. So are urban neighborhoods with inadequate social, institutional, and economic resources. We've seen how something as simple as access to a library or other community center during a heat wave or the option of using a bicycle during a transportation shutdown can make a community more resilient. So too, of course, can smart urban planning and policy across urban regions.

In the New York area, the federal Rebuild by Design competition has begun to offer some answers for urban climate resilience planning at a metropolitan scale. The competition, launched in the wake of Hurricane Sandy, sought proposals from diverse teams of architects, engineers, and researchers to respond to the new realities that the affected region must confront in planning for a future with more extreme storms. The winning projects recognize that success lies in design that reflects deep engagement with communities, policymakers, and other local stakeholders as well as a sophisticated understanding of physical and environmental concerns.

One of the most ambitious ideas to come from the Rebuild by Design competition is a Manhattan coastal defense effort known as the BIG U. ?Currently planned in two segments- the East Side Coastal Resiliency Project and the Lower Manhattan Coastal Resiliency Project- it will wrap the southeastern coast of Manhattan in a protective berm that doubles as parkland and other public recreational facilities to improve access to the waterfront. The designs were developed through extensive engagement and collaboration with community groups from the surrounding neighborhoods and respond to an incredibly diverse set of priorities while reducing the impacts of coastal storms and sea level rise in the area. In so doing, the project aims to seamlessly integrate flood protection into a more livable urban environment with everyday health and community benefits.

Another innovative solution funded by the Rebuild by Design competition is called Living Breakwaters. Located off the shore of New York's Staten Island in one of the areas most devastated by Sandy, the project will involve a system of living, growing tidal breakwaters, built of concrete and recycled glass and seeded with living oysters. As the oyster population grows, the breakwaters will grow too, restoring a cherished native species while attenuating the size and strength of waves and mitigating coastal erosion. Back on shore, restored sand dunes and a community facility and other public spaces oriented toward the seaside will bolster social resilience through educational programming, community amenities, and recreational opportunities. ?All aspects of Living Breakwaters tie in to the Billion Oyster Project, a regional effort to restore New York Harbor' indigenous oyster population.

These projects offer exciting and creative possibilities for building cities that are stronger in the face of storms and also greener and more socially resilient every day.? Of course, resilience is not just about being ready for the coming storms the best defense still comes down to doing what can be done to mitigate climate change in the first place. For cities, this means implementing everyday sustainability efforts across urban regions, from expanding public transportation and bicycle use to reducing waste and energy consumption.? A final Rebuild by Design project called Hunts Point Lifelines exemplifies these concerns as well. This comprehensive proposal for a vital industrial food market and distribution center and its surrounding communities in the South Bronx includes not only needed flood protections and emergency supply routes, but the creation of green jobs, low-carbon cooling and energy production, and transit-oriented development as well.?

In New York, and elsewhere, we are seeing best practices for resilience and mitigation being identified and replicated. ?With an eye on both the social and physical factors at work in urban resilience, we can build cities that are more sustainable and equitable. By building for resilience, cities can show the world how to withstand the challenges of the next century and beyond. By cutting greenhouse gas emissions, cities will ultimately reduce these challenges, and find new ways to flourish.

About the Authors

Gordon Douglas, Associate Director of the Institute for Public Knowledge at New York University, is a sociologist and urban planning scholar who received his PhD from the University of Chicago. His work has appeared in Urban Studies, Architect, City & Community, the Journal of Urban Design, and other publications.

Eric Klinenberg, Professor of Sociology at NYU and Director of the Institute for Public Knowledge, received his PhD at the University of California, Berkeley. He is the author the books Heat Wave, Fighting for Air, Going Solo, Modern Romance (with Aziz Ansari), and many other publications, and has contributed to The New Yorker, The New York Times, Rolling Stone, Le Monde Diplomatique, and more.

NYU&rsquos is an interdisciplinary center for research and programming around issues of contemporary public concern.