It’s one thing to say that climate change is taking its toll on cities, or that 2.5 billion people will pack into urban areas by 2050. It’s another to actually show how the impacts of global warming change over time and how migration patterns look.
That’s where science, data, and visualizations come in, argues Marian Dörk, an information visualization researcher at the University of Applied Sciences Potsdam in Germany. He and his colleagues behind the project Visualizing Cities are at the Habitat III conference this week to showcase how interactive maps contribute to the quest for urban sustainability.
The problem, according to Dörk, is that some of the most daunting challenges facing cities today are also the most complex. That makes them especially difficult for policymakers and urban planners to understand. Recognizing that data visualization can go a long way to solving that problem, Dörk and his team set up an exhibition at the Quito summit featuring dozens of stunning interactive maps and infographics that touch on issues like urban density, housing, and natural disasters. They are among hundreds of projects that journalists, students, and researchers around the globe submitted to a competition earlier this year.
“While basic visualization techniques are becoming canonized, the competition illustrates that there is still a lot of room for experimentation and innovation,”Dörk tells CityLab in an email.
This week, five of those projects were selected as winners, including one that details the migration routes of nearly 7 million people internally displaced by Colombia’s decades-long civil war. As the lines—each indicating the path of one migrant—swarm out of rural areas and into city centers, growing denser as conflict progresses from 1985 to 2015, they illustrate the sheer magnitude of migration brought on by political conflict. The project, created by urban conflict researchers at Columbia University, also creates a mesmerizing look at how urbanization is sometimes forcefully driven by conflict.
“All five winning entries were particularly engaged with ongoing social issues related to cities, such as violent conflict, racial segregation, and inclusiveness,” says Dörk. “[They] do not shy away from the difficult challenges.”
He was particularly intrigued by the “shatter” maps by data scientist Jim Vallandingham, which depicts the racial divide in U.S. cities. The project, which Dörk calls provocative, maps the proportion of white and black residents in cities including St. Louis, Denver, and Memphis. Each city is divided into individual census tracts, which then shatter apart based on how dramatically the racial composition changes from one tract to the next.
“I could easily walk to this very affluent shopping mall, while still being right next door to what was perceived to be a dangerous part of town,” Vallandingham told CityLab in 2015. Though the project has its limits, it’s a “visceral and emotional” way to highlight the phenomenon of segregation, he says.
Here’s how Baltimore, Maryland, looks:
Dörk is part of Habitat X Change, a network of researchers, ecologists, engineers, and data scientists pushing for science to have a larger role in implementing global urban agendas. Writing in the journal Nature this month, urban ecologist Timon McPhearson called for a boost in funding and policy support from governments, as well as the formation of an international urban scientific body. He argued that urban research has been “disparate, marginalized, and ill-prepared to interact effectively with global policy.” Yet, evidence is key to successfully implementing the Sustainable Development Goals and the New Urban Agenda.
And one way to present evidence is through simple, but effective data visualization projects. Earlier this week, many Habitat III attendees got their first look at The Atlas of Urban Expansion, a new online tool that can help monitor progress and identify trends in the implementation of the New Urban Agenda. Created by researchers at New York University, UN-Habitat, and the Lincoln Institute of Land Policy, the atlas uses historical maps and satellite imagery to illustrate urban sprawl in 200 global cities. It shows how each city physically expands in relation to its population growth.
Over the course of the four-day conference, which ends Thursday, Dörk and several data scientists held panels and workshops to get city leaders better acquainted with the variety of data and mapping tools available. He says while many are open—eager, even—to experiment, some remain skeptical. Others lack the technical expertise and the confidence.
The good news is that “mapping and visualization is becoming increasingly accessible,” he says. “There are more and more tools that let people analyze and visualize data without having to be a software developer or statistician.”
Take the Chennai Flood Map, another winning entry of the Visualizing Cities competition. While the Indian city was getting inundated with historic rainfall last year, a small group of designers at Mapbox and OpenStreetMap created a tool to help with relief efforts. The digital map crowdsourced information from citizens to identify in real time exactly which streets were flooded and where the nearest relief camps were. According to the competition website, the group received roughly 15,000 reports of flooded streets and garnered more than a million views.
Mapbox and OpenStreetMap offer open-source data and mapmaking platforms, offering their accessibility to not only DIY cartographers, but also governments. In fact, Mapbox recently launched a mentorship program to help cities gather and make use of data to solve their most pressing challenges. Since the launch of the Chennai Flood Map, the creators have offered to help cities expand and tweak it to their own specific needs. And at least one city, Dar es Salaam in Tanzania, has taken advantage of the opportunity.