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Can the rubble of history help shape today’s resilient cities?

David Sislen's picture
Ruins of the Church of Saint Paul, following the 1755 Lisbon earthquake. (Photo via Wikimedia Commons)
Ruins of the Church of Saint Paul, following the 1755 Lisbon earthquake. (Photo via Wikimedia Commons)

Did you know that, in 1755, Portugal suffered a catastrophic disaster so severe that it cast a long shadow over politics, religion, philosophy, and science?

During an All Saints’ Day mass in Lisbon in that fateful year, an 8.5-magnitude earthquake collapsed cathedrals, triggered a 20-foot tsunami, and sparked devastating fires that destroyed nearly 70% of the city’s 23,000 buildings.

The death toll was estimated between 10,000-50,000, leaving the center of a global empire in ruins, with losses equivalent to 32%-48% of Portugal's GDP at the time.

Never in the European history had a natural disaster received such international attention.

The “Great Lisbon Earthquake” had a resounding impact across Europe: Depictions of the earthquake in art and literature – the equivalent of today’s mass media – were reproduced for centuries and across several countries. Rousseau, influenced by the devastation, argued against large and dense cities in the wake of the disaster, while Immanuel Kant published three separate texts on the disaster, becoming one of the first thinkers to attempt to explain earthquakes by natural, rather than supernatural, causes.

In the years to follow, careful studies of the event would give rise to modern seismology.

Reversing the geospatial digital divide – one step, or leap, at a time

Anna Wellenstein's picture
Earth from space. Photo by NASA.

Global positioning systems (GPS), real time traffic maps, accurate weather forecasts, Uber, self-driving cars… Geospatial data is on full display 24/7 throughout the world these days.  It’s like nothing we have seen before. But none of this would be possible without the underpinning role of the government.

“Geospatial,” or location-based data has existed for hundreds of years – for example, in street and topographical maps. What’s different is how quickly new information is being gathered and the more sophisticated analytics that is being applied to it, thanks to technological advances.

What was once information only found in the domain of government, military, and select private sector, even up to the 1980s and 90s, has come into broad use over the last 20 years. With the increase of mobile technology and communications, handheld smart phones have democratized mapping, moving geospatial technology into the hands of every individual.

This summer, some tens of millions of people in the U.S. traveled to see the total solar eclipse, including a co-author of this blog. Not only was the eclipse amazing – but the drive back from Tennessee to Washington, D.C. showed the integration and impact of geospatial information in our daily lives.
 

How should we design disability-inclusive cities?

Ede Ijjasz-Vasquez's picture
 

Urbanization has been one of the most significant driving forces of recent global development, with more than half the world’s population now living in cities. And this proportion will continue to rise. Add to this, the United Nation’s Sustainable Development Goal 11 that calls for “inclusive, safe, resilient and sustainable” cities.

In this edition of the Sustainable Communities Blog, Ede Ijjasz-Vasquez (@Ede_WBG), Senior Director of the World Bank’s Social, Urban, Rural and Resilience Global Practice, sat down with Dr. Shazia Siddiqi, Executive Director of Deaf Abused Women’s Network (DAWN), for a conversation on the disability dimension of inclusion and how we should conceive and design cities that are truly inclusive of all, including persons with disabilities.

DAWN is a non-profit organization servicing the Washington, D.C., area with a mission to promote healthy relationships and end abuse in the Deaf community through providing survivors of abuse the help they need to heal and progress with lives, and through community education on how to foster positive relationships.

This wide-ranging discussion touches on several key issues that are crucial for sustainable and inclusive development and important for breaking down barriers of exclusion. Particularly given the prevalence of persons with disabilities moving to cities, the topics include how to incorporate disability inclusive technology into smart city planning, disaster risk management (DRM), and attitudes that enhance the dignity of persons with disabilities.

Let’s make a deal for resilient cities

Carina Lakovits's picture
Photo credit: humphery / Shutterstock.com
JIANGXI CHINA-July 1, 2017: In Eastern China, Jiujiang was hit by heavy rain, and many urban areas were flooded. The vehicles were flooded, and the citizens risked their passage on flooded roads.
Photo credit: humphery / Shutterstock.com
For the first time in history, more people live in cities than in rural areas. Although cities hold the promise of a better future, the reality is that many cities cannot live up to expectations. Too often, cities lack the resources to provide even the most basic services to their inhabitants, and cities all over the world fail to protect their people effectively against the onslaught of natural disasters or climate change.

Much of this has to do with the lack of adequate infrastructure that can defend against the impacts of floods, sea level rise, landslides or earthquakes. Most cities need better flood defenses, better constructed houses, and better land use planning. But even when cities know what it takes to become more resilient, most often they do not have access to the necessary funding to realize this vision.

It is estimated that worldwide, investments of more than $4 trillion per year in urban infrastructure will be needed merely to keep pace with expected economic growth, and an additional $1 trillion will be needed to make this urban infrastructure climate resilient.  It is clear that the public sector alone, including development finance institutions like the World Bank, will not be able to generate these amounts—not by a long stretch.

Natural disasters are in 3D – and the rights that protect against them should be as well

Luis Triveno's picture
Photo credit: studiovin/Shutterstock


The recent series of devastating hurricanes in the Caribbean has reminded the world, once again, that natural disasters are not equal-opportunity destroyers. The economically marginalized and those lacking secure land and property rights are often disproportionately affected for at least three reasons:

The Roadmap for Safer Schools—a conversation on making school infrastructure more resilient to natural disasters

Fernando Ramírez's picture
Global Program for Safer Schools

Imagine that you are an advisor to your country's Minister of Education. A recent earthquake damaged hundreds of schools in several cities. The minister has called for a meeting with you and asked: What are the main factors that contribute to the vulnerability of our school infrastructure? What can be done to prevent similar damages in the future?

So… What would you advise?

In search of answers, we spoke with the leaders of the World Bank’s Global Program for Safer Schools (GPSS), who have recently launched an innovative tool, the Roadmap for Safer Schools. This roadmap is a guide to design and implement systematic actions to improve the safety and resilience of school infrastructure at risk from natural hazards. 

 

A road by any other name: street naming and property addressing system in Accra, Ghana

Linus Pott's picture
Street names in Accra, Ghana
Street names in Accra, Ghana. Photo credit: Ben Welle/ Flickr CC
When I used to work in Rwanda, I lived on a small street in Kigali. Every time I invited friends over, I would tell them to “walk past the Embassy, look out for the Church, and then continue to the house with the black gate.” The day a street sign was erected on my street was a game changer.
 
So how do more than two million citizens of Accra navigate the busy city without the help of street names? While some street names are commonly known, most streets do not have any official name, street sign or house number. Instead, people usually refer to palm trees, speed bumps, street vendors, etc.

But, what happens when the palm tree is cut or when the street vendor changes the location?

The absence of street names poses not only challenges for orientation, but also for property tax collection, postal services, emergency services, and the private sector. Especially, new economy companies, such as Amazon or Uber, depend on street addressing systems and are eager to cater to market demands of a growing middle class.

To address these challenges, the Accra Metropolitan Assembly (AMA), financed by the World Bank’s second Land Administration Project , is implementing a street addressing and property numbering system in Accra. Other Metropolitan areas received funding from other World Bank-funded projects for similar purposes.
 

Making homes safer to build resilient cities

Kristina Wienhoefer's picture

Children are often told that home is where to run inside when thunders hit or when the rain comes, and that home is a safe place. However, for billions of people in the world, it is not.
 
By 2030, it is estimated that 3 billion people will be at risk of losing a loved one or their homes—usually their most important assets—to natural disasters. In fact, the population living on flood plains or cyclone-prone coastlines is growing twice as faster as the population in safe homes in safer areas.
 
Due to climate change, extreme weather and other natural hazard events hit these populations harder and more often. The 10 natural disasters causing the most property damages and losses in history have occurred since 2005. The damages and losses were highly concentrated in the housing sector. While the poor experience 11% of total of asset losses, they suffer 47% of all the well-being losses. Worse, natural disasters can lead to unnecessary losses of life, with earthquakes alone causing 44,585 deaths on average per year. This is an issue that policymakers and mayors need to address if they don’t want their achievements in poverty reduction to be erased by the next hurricane or earthquake.

World Bank Group

What can satellite imagery tell us about secondary cities? (Part 2/2)

Sarah Elizabeth Antos's picture
In the previous blog, we discussed how remote sensing techniques could be used to map and inform policymaking in secondary cities, with a practical application in 10 Central American cities. In this post, we dive deeper into the caveats and considerations when replicating these data and methods in their cities.

Can we rely only on satellite? How accurate are these results?

It is standard practice in classification studies (particularly academic ones) to assess accuracy from behind a computer. Analysts traditionally pick a random selection of points and visually inspect the classified output with the raw imagery. However, these maps are meant to be left in the hands of local governments, and not published in academic journals.

So, it’s important to learn how well the resulting maps reflect the reality on the ground.

Having used the algorithm to classify land cover in 10 secondary cities in Central America, we were determined to learn if the buildings identified by the algorithm were in fact ‘industrial’ or ‘residential’. So the team packed their bags for San Isidro, Costa Rica and Santa Ana, El Salvador.

Upon arrival, each city was divided up into 100x100 meter blocks. Focusing primarily on the built-up environment, roughly 50 of those blocks were picked for validation. The image below shows the city of San Isidro with a 2km buffer circling around its central business district. The black boxes represent the validation sites the team visited.
 
Land Cover validation: A sample of 100m blocks that were picked to visit in San Isidro, Costa Rica. At each site, the semi-automated land cover classification map was compared to what the team observed on the ground using laptops and the Waypoint mobile app (available for Android and iOS).

What can satellite imagery tell us about secondary cities? (Part 1/2)

Sarah Elizabeth Antos's picture

The buzz around satellite imagery over the past few years has grown increasingly loud. Google Earth, drones, and microsatellites have grabbed headlines and slashed price tags. Urban planners are increasingly turning to remotely sensed data to better understand their city.

But just because we now have access to a wealth of high resolution images of a city does not mean we suddenly have insight into how that city functions.

The question remains: How can we efficiently transform big data into valuable products that help urban planners?

In an effort a few years ago to map slums, the World Bank adopted an algorithm to create land cover classification layers in large African cities using very high resolution imagery (50cm). Building on the results and lessons learned, the team saw an opportunity in applying these methods to secondary cities in Latin America & the Caribbean (LAC), where data availability challenges were deep and urbanization pressures large. Several Latin American countries including Argentina, Bolivia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama were faced with questions about the internal structure of secondary cities and had no data on hand to answer such questions.

A limited budget and a tight timeline pushed the team to assess the possibility of using lower resolution images compared to those that had been used for large African cities. Hence, the team embarked in the project to better understand the spatial layout of secondary cities by purchasing 1.5 meter SPOT6/7 imagery and using a semi-automated classification approach to determine what types of land cover could be successfully detected.

Originally developed by Graesser et al 2012 this approach trains (open source) algorithm to leverage both the spectral and texture elements of an image to identify such things as industrial parks, tightly packed small rooftops, vegetation, bare soil etc.

What do the maps look like? The figure below shows the results of a classification in Chinandega, Nicaragua. On the left hand side is the raw imagery and the resulting land cover map (i.e. classified layer) on the right. The land highlighted by purple shows the commercial and industrial buildings, while neighborhoods composed of smaller, possibly lower quality houses are shown in red, and neighborhoods with slightly larger more organized houses have been colored yellow. Lastly, vegetation is shown as green; bare soil, beige; and roads, gray.

Want to explore our maps? Download our data here. Click here for an interactive land cover map of La Ceiba.

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