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Science and the City

Making Urban Development Sustainable

By Alan Dove, PhD, NYAS Contributor

In 1900, about 13 percent of the world's population lived in cities. Today, well over half of it does, and that proportion continues to grow. Cities now account for three-fourths of global gross domestic product, and about the same fraction of human-generated carbon emissions.

Because they concentrate huge amounts of human activity into small areas, cities are ideal test beds for new sustainability efforts. Inspired by the United Nations' Sustainable Development Goals (SDGs) new collaborations have sprung up between political leaders, scientists, communities and non-governmental organizations. From global data-sharing efforts to local educational campaigns, these new urban sustainability projects are shaping the cities of the future.

Christiana Figueres

Christiana Figueres

The Political Climate

Nations formally sign international agreements such as the SDGs, but in the case of urban sustainability, it falls to the leaders of individual cities to implement relevant policies. Fortunately, compared to national or regional governments, “cities are much more in tune with the direct impact of their policies, and they are much more in tune with the quality of life of citizens ... from day to day,” says Christiana Figueres, Vice Chair of the Brussels-based Global Covenant of Mayors for Climate and Energy.

Figueres’ group provides a global network through which city leaders can share their ideas and results in pursuing sustainability. "We're a very important platform for city officials to learn what has worked," says Figueres. She points to examples such as Seoul's renewable energy campaign, Paris' expanding bicycle infrastructure, and a multi-city effort in India that has exchanged over 700 million incandescent lightbulbs for high-efficiency ones.

The central focus of the Global Covenant of Mayors is helping cities design and implement ambitious climate action plans, but that remit intersects with many of the U.N.'s other SDGs. “How we pursue building our cities for the future — such as using high-carbon or low-carbon infrastructure, the way we change our consumption and production patterns, the way we deliver economic growth — are all relevant to the sustainable development goals and will largely determine the quality of life on this planet,” says Figueres.

While cities around the world face common problems, they're also bound by the particular laws and circumstances of their nations. Figueres emphasizes that the Global Covenant of Mayors has neither the authority nor the desire to try to synchronize urban policies across national boundaries. Instead, the group serves as a clearinghouse for cities to share data, strategies and ideas and discuss their experiences and results.

Science is a central part of all of these efforts, in measuring greenhouse gas emissions, studying and predicting the potential impacts of future climate change and also identifying the most effective measures cities can take to reduce their environmental impact and mitigate risks. Figueres points to a project in Myanmar, where scientists are developing models that can predict storm surges from cyclones, and others that identify areas at the highest risk of earthquakes and fires. That information will help local leaders plan disaster responses to focus on the areas with the greatest needs, while also guiding future infrastructure development. Data from that project could inform similar efforts in coastal cities around the world, as rising seas and temperatures will likely make natural disasters more frequent.

Climate change is fundamentally a problem of physics and atmospheric chemistry, but responding to it will require many other disciplines. Figueres emphasizes that in cities especially, researchers need to focus on social aspects of sustainability. "We have a tendency to dehumanize cities, as though the purpose of cities were to have buildings and infrastructure, [but] the purpose of cities is actually to be the home for human beings," says Figueres.

For policymakers to make the best use of science, scientists also need to explain it in human terms. "It does no good to come with science, accurate as it may be, if it's not made relevant and understandable," says Figueres.

Melanie Uhde Photo: Sun Kim, skstudiosnyc

Melanie Uhde 
Photo: Sun Kim, skstudiosnyc

Hungry for Change

While the Global Covenant of Mayors is helping scientists and city leaders work together globally, individual researchers are also taking local action in their own towns. New York's Urban17 Initiative exemplifies this trend. "I wanted the students who are part of our team to focus on urban sustainability in New York City, because it's a great city to model hypotheses," says Melanie Uhde, Urban17's founder and managing director.

Urban17 currently consists of about a half-dozen volunteer analysts, mostly graduate students and young researchers from different disciplines and universities around the city. Despite its small size and lack of funding, the ambitious group is already tackling a project with global relevance, studying the overlapping problems of obesity and hunger. "We know that, for example, the rates of obesity and hunger in the Bronx are the highest [in the city], so they're basically bedfellows, which is a very common phenomenon in urban environments throughout the world," says Uhde.

It may seem paradoxical for hunger and obesity to overlap, but interconnected problems can yield exactly that result. "It's definitely poverty, but it's unfortunately much more complicated," says Uhde, adding "even if you have money, do you have access to food, do you have the education, do you know what's actually good for you, [and] do you have the time to put effort into a nutritious meal?" In poor urban neighborhoods, the answers to those questions are often 'no,' causing  synergistic deficits that can produce the entire spectrum of dietary problems.

To address that, Uhde and her team are combining data on obesity and hunger with the locations of groceries, parks, fitness centers and schools.

Public schools provide good anchors for the project, not only in mapping the extent of obesity and hunger in some of the most vulnerable populations, but also in implementing solutions. "Education is a very important factor to achieve sustainability, and we're seeing [how] other factors like obesity or hunger influence education," says Uhde. Malnourished students aren't likely to learn well, which in turn can perpetuate poverty and poor health. Improving school meal programs and health classes could help break that cycle.

Uhde hopes other scientists will start tackling sustainability problems in their own towns. “Sustainability ... affects everyone in every aspect of life,” she says, adding that “we're living in this era where we have to do something no matter what.”

Jennifer Costley, PhD, Director, Physical Sciences, Sustainability and Engineering, New York Academy of Sciences contributed to this story.

7 World Trade Center — A Sustainable Office

By Robert Birchard, NYAS Staff

The New York Academy of Sciences’ office at 7 World Trade Center (7 WTC) was the first office building in New York City to receive a LEED (Leadership in Energy and Environmental Design) gold rating for its shell and core.  Sustainable buildings not only reduce maintenance and operation costs, but can improve employee health and productivity.

Gold rated LEED buildings must meet a variety of energy-saving and sustainability standards. For example, recycled materials were used throughout construction of 7 WTC, most notably recycled steel for the structural beams, while fly ash — a byproduct of burnt coal — supplemented the building’s concrete. During construction 90 percent of the solid waste generated by the project was recycled.

The building makes productive use of rainwater which is collected and stored in tanks on the building’s roof, and beneath Silverstein Family Park, a “green space” located across from the 7 WTC entrance.  The rainwater is used for the building’s heating, ventilation, air-conditioning system and to irrigate the park. Using rainwater has reduced sewer run-off by 25 percent.

The building’s 13.6 foot-long sheets of ultra-clear “water white glass,” are designed to maximize the entrance of light, while keeping out unwanted solar heat. Offices are kept cool in the summer by the “ceramic frit” embossed at the top of each window that absorbs the summer heat. The incoming natural light, combined with interior lighting controls, can result in a 10 percent energy savings.

A light-dimming system in the ceilings adjusts to the amount of available sunlight. High-efficiency cooling and heating systems employ filters to improve indoor air quality. Offices are further ventilated by the rooftop air intake that utilizes activated carbon to clean the building’s air.

High-efficiency plumbing systems, such as automatic faucets and low-flow automatic flush toilets have reduced water consumption throughout the building by at least 30 percent.

The building’s elevators are integrated with the security system. Visitors and workers are directed to a smart elevator that already knows their destinations. An algorithm directs the minimum number of elevators to efficiently deliver the maximum number of visitors to their destination.

7 World Trade Center, headquarters of the New York Academy of Sciences. Photo: Joe Woolhead

Green is the New Black in Fashion

By Mandy Carr, NYAS Staff

How much stuff do you have in your closet? If you’re like most people, it’s way too much and with clothing you probably seldom wear. According to Mattias Wallander, CEO of USAgain, Americans purchase five times as much clothing as they did in 1980 — largely due to “fast-fashion” — low-quality, inexpensive fashions typically found at retailers like H&M and Forever 21. As a result, textile waste grew 40 percent between 1999 and 2009, according to the Council for Textile Recycling. In 2014 the EPA reported that 10,460,000 tons of textile waste was thrown into landfills.

In the State of Fashion 2018 report by Business of Fashion and McKinsey & Company, Dame Ellen MacArthur said, “Today’s textiles economy is so wasteful that in a business-as-usual scenario, by 2050 we will have released over 20 million tons of plastic microfibers into the ocean.” Those stats show a frightening trend, but according to a 2014 article in The Atlantic, of the clothing that is collected by charities: 45 percent is used for second hand clothing, 30 percent is cut down and made into industrial rags, 20 percent is ground down and reproduced and five percent is unusable. Less than one percent is recycled into new textile fiber.

So why isn’t more disused clothing being recycled? According to Natasha Franck, the founder of EON, a collective focused on making fashion sustainable, the biggest barrier to recycling textiles is the lack of material transparency. Fabric cannot be recycled if its composition is unknown. Seventy percent of retailers plan to provide item level tagging by 2021 and EON is developing the first global tagging system for textile recycling, making it easier to sort through fabrics.

Some retail companies are developing their own solutions. International fashion retailer Zara, for example, is installing collection bins across all its stores in China, while Swedish retailer H&M, has invested in Re:Newcell the first garment in the world made from chemically recycled used textiles. C&A introduced a mass market price T-shirt that is “Cradle-to-Cradle” certified i.e. designers and manufactures have undergone a continual improvement process that looks at five quality categories; material health, material reutilization, renewable energy and carbon management, water stewardship, and social fairness. Each product receives a level of achievement in each category — basic, bronze, silver, gold or platinum.

Many cities have their own recycling programs. New York City has NYC Grow collection points to donate clothing. Unwanted clothes are picked up at collection stations and then taken to a facility to be sorted and recycled. Germany-based I:CO — short for I:Collect — provides global solutions for collection, reuse and recycling of used clothing and shoes. Their worldwide take-back system and logistics network currently operates in 60 countries and helps cities and retail outlets to develop recycling solutions.

Note: The Academy is in the planning phase for a program on fashion sustainability. Check the Academy website at for updates.

Students Envision a Neural Network to Build a Better, Greener Future

By Lori Greene, NYAS Contributor

Today’s students will be the inhabitants of tomorrow’s cities, so they want more sustainable ways of living and working in urban ecosystems. That was the premise behind United Technologies’ Future of Buildings Innovation Challenge created by the New York Academy of Sciences and launched in September, 2017. Fifty-two teams of students 13 to 18 years old from across the globe competed to conceive the most inventive green building solution.

Imagining an “Intellicity,” where neural networks run a building’s systems to ensure that people, machines and the environment work in concert to adroitly use and conserve available resources, was the creation of one team.

In the “Intellicity” paradigm, little is wasted.  Solar panels and wind turbines create an on-going source of clean, abundant, renewable energy, while rainwater collected from the roofs of buildings provide water for indoor plumbing and hydroponic systems. Once inside, hydroponic walls can repurpose rainwater for food growth. Intellicity’s student founders want to ensure that people are harnessing energy generated by city activity and putting it to use. Floor tiles in larger structures convert footsteps into electrical energy, and waste is turned into fertilizer.  Solar panels on windows maximize sunlight and capture the energy to help run a building’s lighting and temperature systems.  Revolving doors connected to electric generators can be used to capture energy as people walk in and out, creating another source to power the structure’s electricity, heating and cooling needs.

Using artificial intelligence (AI), energy is redistributed to increase the comfort and productivity of building occupants. The AI system that would run the integrated interior and exterior building networks “learns” from several inputs and the resulting outputs.  For example, during high usage times, the power could go towards controlling lighting as well as heating and cooling rooms. Over time, the network records occupant preferences and automatically adjusts the room, heat and light depending on who enters and leaves.

In a similar way, the team was looking to give people an opportunity to interact with their building using a “neural network,” a computer system developed around the human nervous system, to allow the building to communicate back through an app detailing the energy being collected, used and wasted in the structure.

With the flexibility of AI, the team imagines that all of this can also be implemented in a variety of structures ranging from transportation hubs such as airports, to office and apartment buildings. According to the plan, each section of the building could provide sustainable energy with minimal impact to the environment around it. Rather than redesigning structures, the team suggests using sensors in every room along with monitoring software that can help devise a customized solution to redistribute energy exactly where and when it’s needed.

Integrating neural networks into buildings to create an energy efficient sustainable future is Intellicity’s ultimate goal.

Check: for information about the UTC Future Buildings and Cities Challenge winners.