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Mapping and measuring urban places: Are we there yet? (Part 2/2)

David Mason's picture
Photo by Anton Balazh via Shutterstock

My previous blog post surveyed some of the recent trends in developing global measures of urbanization. In this post, I want to turn to a brief discussion for scholars and practitioners on some possible applications and areas of focus for ongoing work:
 
[Download draft paper "Bright Lights, Big Cities: a Review of Research and Findings on Global Urban Expansion"]
 
While there are a number of different maps for documenting urban expansion, each has different strengths and weaknesses in application. Coarser resolution maps such as MODIS can be used for mapping the basic contours of artificial built-up areas in regional and comparative scales. On the other hand, high-resolution maps are best suited for individual cities, as algorithms can be used to identify and classify observed colors, textures, shading, and patterns into different types of land uses. These levels of detail are difficult to use for reliable comparisons between cities as the types of building materials, structure shapes, light reflectivity, and other factors can vary widely between countries and regions.
 
Nonetheless, there are a number of applications for policymakers in this regard, from identifying and mapping green spaces and natural hazard risks to identifying and tracking areas of new growth, such as informal settlements. However, such approaches to land use detection require careful calibration of these automated methods, such as cross referencing with other available maps, or by “ground truthing” with a sample of  street-level photos of various types of buildings and land cover as reference inputs for automation. One solution to this is the use of social media and geo-coded data to confirm and monitor changes in urban environments alongside the use of high-resolution satellite imagery.
 
Nighttime light maps also have gained traction as measures of urban extent and as ways to gauge changes in economic activity in large urban centers. They are probably less useful for documenting smaller settlements, which may be dimmer or have little significant variation in brightness. It is important to correct these types of maps for “overglow” measurement effects—where certain light may “bleed” or obscure the shapes and forms of very large, bright urban areas in relation to adjacent smaller and dimmer settlements (newer VIIRs maps have made some important advances in correcting this).

Mapping and measuring urban places: are we there yet? (Part 1/2)

David Mason's picture
Source: Deuskar, C., and Stewart B.. 2016. “Measuring global urbanization using a standard definition of urban areas: Analysis of preliminary results” World Bank
This satellite image shows Sao Paolo's estimated “urban areas” based on a WorldPop gridded population layer. Areas in yellow are areas with at least 300 people per km2 and a known settlement size of 5,000 people. Red areas represent a population density threshold of at least 1,500 people per km2 and a known settlement size of 50,000 people.
There remains a surprising amount of disagreement over precisely what “urban” means despite the ubiquity of the term in our work. Are urban areas defined by a certain amount of artificial land cover such as permanent buildings and roads? Or are they more accurately described as spatially concentrated populations? The answer often depends on what country you are in, as their administrative definitions of urban areas can vary widely across and between these two dimensions.
 
Without a globally consistent measure of urban areas, it can be difficult to track changes in built-up areas (land surface coverage comprised of buildings and roads) and population growth across time and space. This impacts how policymakers may understand and prioritize the challenges cities face and what investments or reforms may be needed. In a new paper, “Bright Lights, Big Cities: a Review of Research and Findings on Global Urban Expansion,” I provide a brief introduction to some of the current approaches for measuring urban expansion and review the comparative findings of some recent studies.
The UN’s World Urbanization Prospects (WUP), perhaps the most comprehensive and widely cited measure of urbanization across the world, draws from a compilation of country-level population totals based on administrative definitions. A key weakness with this set is that since each country defines “urban” differently, it is difficult to accurately compare one country’s urbanization to another, as well as to estimate the urban population of a group of countries or the world itself. Recent work has provided more sophisticated ways to measure urban growth and expansion using both satellite map data and careful application of population data.

Cultural heritage and sustainable tourism: drivers of poverty reduction and shared prosperity

Ede Ijjasz-Vasquez's picture
Old City of Dubrovnik, a UNESCO World Heritage Site in Croatia. (Photo by Justin Smith / Flickr CC)
Old City of Dubrovnik, a UNESCO World Heritage Site in Croatia. (Photo: Justin Smith / Flickr CC)

Today, we celebrate the International Day for Monuments and Sites. This year, the day focuses on Cultural Heritage and Sustainable Tourism, which underlines the important linkage between culture and cities: Culture, identity, and a people-centered approach are central to building the urban future we want and ensuring sustainable urban development.

In relation to the United Nations International Year of Sustainable Tourism for Development, and in the context of the 2030 Agenda for Sustainable Development and the New Urban Agenda this day also presents a unique opportunity to celebrate the long-standing partnership between the World Bank and UNESCO in the area of culture and sustainable development. 

The recently-launched UNESCO Global Report on Culture for Sustainable Urban Development titled Culture: Urban Future has brought to the forefront of the global discussion the critical role that culture should play in achieving sustainable urbanization, especially over the coming years when one billion people are expected to move to cities by 2030. Culture does not necessarily come in the list of Top 10 issues for sustainable urban development, but it is.

Culture is an essential component of the safe, inclusive, resilient and sustainable urban settlements everybody wants to live in. Culture should be at the core of new approaches for people-centered cities, quality urban environments and integrated policy-making.

Specifically, culture contributes to urban development in four aspects. All of them linked to poverty eradication and shared prosperity in a sustainable manner:

Cleaner streets mean healthier communities: The story of the “Zika Warriors”

Silpa Kaza's picture


Last November, 345 “Zika Warriors” took to the streets of Jamaica to fight the spread of the Zika virus in 30 communities. These local residents trained as vector control aides to prevent Zika primarily by improving waste management in their communities, including cleaning up public spaces and destroying mosquito breeding sites. In addition, they distributed bed nets to pregnant households.

As we observe World Health Day today, we look back with great thanks to the significant reduction in Zika in these communities. Anecdotal evidence suggested that the Zika Warriors significantly stemmed the spread of the virus, especially compared to the 2014 Chikungunya outbreak that led Jamaica to declare a state of emergency.

As a first responder to the pandemic, the Jamaica Social Investment Fund (JSIF) designed this program within an existing waste management program of the World Bank’s Integrated Community Development Project, directly benefitting more than 140,000 citizens.

Urban jungles in jeopardy

Ivo Germann's picture
Why the world’s cities are at risk – and what we can do to make them more resilient



We may not know exactly what the world will look like in two decades, but we know this: it is going to be a world of cities.
 
The global population is becoming increasingly urban, and at an astonishing rate. Each year, urban areas are growing by an average of more than 75 million people – more than the population of the world’s 85 smallest countries combined.
 
For the world’s economy, this is great news, since cities produce 80 percent of global GDP, despite currently being home to only 55 percent of the population. But it is a problem for urban infrastructure, which can’t keep up with such fast-paced growth. As a result, cities, already vulnerable, are becoming increasingly susceptible to natural disasters – from flooding and landslides that can decimate informal housing settlements, to earthquakes that can devastate power grids and water systems.
 
These risks could be disastrous for the urban poor, 881 million of whom currently live in slums (up 28 percent since 2000). And climate change – which is increasing the intensity and frequency of natural disasters – will only exacerbate the problem. For this reason, multilateral and government institutions now see resilience and climate adaptation as integral pillars of development.
 
The Swiss State Secretariat for Economic Affairs (SECO), for example, considers low-emission and climate-resilient economies to be key to global competitiveness. A recent report by the World Bank and the Global Facility for Disaster Reduction and Recovery (GFDRR) found that climate change may force up to 77 million urban residents into poverty by 2030 – unless we take action to improve the resilience of cities around the world.

In China, conserving the past helps the poor build a brighter future

Ede Ijjasz-Vasquez's picture
How cultural heritage and sustainable tourism help reduce poverty
 
China has seen a booming tourism industry during the last few decades, thanks to a fast-developing economy and growing disposable personal income. In 2015 alone, the travel and tourism sector contributed to 7.9% of China’s GDP, and 8.4% of the country’s total employment. Not surprisingly, cultural heritage sites were among the most popular tourist destinations.

But beyond the well-known Great Wall and Forbidden City, many cultural heritage sites are located in the poorer, inland cities and provinces of the country. If managed sustainably, tourism in these areas can serve as a unique opportunity to help local communities—especially ethnic minorities, youth, and women—find jobs, grow incomes, and improve livelihoods.
 
“[Sustainable tourism] is not only the conservation of the cultural assets that are very important for the next generations to come, but, also, it’s the infrastructure upgrading, it’s the housing upgrading, and it is the social inclusion to really preserve the ethnic minorities’ culture and values – it is an interesting cultural package that is very valuable for countries around the world,” says Ede Ijjasz-Vasquez, a Senior Director of the World Bank.
 
To help reduce poverty and inequality in China’s lagging regions, the World Bank has committed to a long-term partnership with China on cultural heritage and sustainable tourism—with the Bank’s largest program of this kind operating around 20 projects across the country. These projects have supported local economic development driven by cultural tourism.
 
“Over the years, the program has helped conserve over 40 cultural heritage sites, and over 30 historic urban neighborhoods, towns, and villages,” according to Judy Jia, a Beijing-based Urban Analyst.
  
Watch a video to learn from Ede Ijjasz-Vasquez (@Ede_WBG) and Judy Jia how cultural heritage and sustainable tourism can promote inclusive growth and boost shared prosperity in China, and what other countries can learn from this experience.



Also available in: 中文

How to effectively manage metropolitan areas?

Ede Ijjasz-Vasquez's picture
​Today, a quarter of the world’s population lives in urban “agglomerations”—supersized metropolitan areas that cut across jurisdictional boundaries and bring together one or more cities along with their surrounding areas.

These metropolitan areas face a common challenge: effectively coordinating planning, infrastructure development, and service delivery across multiple jurisdictions. This is particularly difficult in developing countries, which often lack the necessary legal, institutional, and governance apparatus to undertake such coordination. The New Urban Agenda issued by the Habitat III conference in 2016 identified metropolitan planning and management as one of the most critical needs to ensure sustainable urbanization.

Fortunately, there is growing evidence and good practice from various countries on how to effectively manage and govern metropolitan areas. To help spread existing good practice and co-create new solutions, the World Bank has been supporting a community of practice (CoP) on metropolitan governance, or MetroLab, which brings together officials from metropolitan areas in both developing and developed countries for peer-peer knowledge and experience sharing.  Since its launch in 2013, MetroLab has held eight meetings in various cities, including Bangkok, Mumbai, New York, Paris, Rio de Janeiro, and Seoul.

​The most recent meeting took place in Tokyo from January 30 through February 2. Organized by the World Bank’s Tokyo Development Learning Center, the Tokyo MetroLab brought together mayors, city planners, and finance officials from nine developing cities. They were joined by experts from the World Bank, New York’s Regional Plan Association, the Seoul Metropolitan Government, and Advancity—Paris’ Smart Metropolis Hub.

In this video, Lydia Sackey-Addy, one of the participating officials from Accra, Ghana, as well as the World Bank’s Senior Director Ede Ijjasz-Vasquez (@Ede_WBG) and Lead Urban Economist Maria Angelica Sotomayor (@masotomayor) tell us how they are working together to make the Accra metropolitan area more resilient and sustainable for its residents.


 

How can Kenya achieve a sustainable urban future?

Ede Ijjasz-Vasquez's picture
Cities in Africa are growing at unprecedented speeds. In Kenya, about 12 million of the country’s over 40 million people live in urban areas today. However, a child born in 2017 will see Kenya’s urban population double to 24 million by 2035 and more than triple to 40 million by 2050. A World Bank report titled “Kenya Urbanization Review” projects that by that time, about half of Kenyans will be living in cities, and Kenya’s urban population will be nearly as large as the country’s entire population today. Kenya’s urban transition has begun.
 
Despite many advantages including an ambitious program for devolution, the challenges for a smooth urbanization process remain multifaceted for Kenya:
  • Access to services remains low;
  • Informality of human settlements and jobs predominate; and
  • Poorly functioning land markets make investing in housing and infrastructure expensive and inefficient. 
The Kenya Urbanization Review points to some policy recommendations that can help Kenya ensure the smoothest transition possible during its ongoing urbanization process.

In this video, Senior Director Ede Ijjasz-Vasquez weighs in on Kenya’s urbanization challenges, focusing on urban finance, land and planning institutions, and urban governance, as he discusses the main messages of the Kenya Urbanization Review.

Video: Courtesy of Arimus Media

Three misconceptions in the way of better housing policies

Luis Triveno's picture
Also available in: 中文

Photo by Dominic Chavez / World Bank

​While the need for housing is widespread, individually people have different needs—depending on whether they are single, married, senior citizens, families with children, or members with disabilities. Despite the best of intentions of policymakers, "a roof overhead" remains an elusive goal for a large majority of the world’s people. Most households cannot afford even the cheapest house that fits their needs and qualifies as “decent,” and no government alone can close this gap with subsidies. Nor are we on track to build the 300 million new houses needed to close the housing gap by 2030.

What’s missing? At least three misconceptions stand in the way of better housing policies: 
 

All I need is the air that I breathe…

Anna Gueorguieva's picture

Also available in: 中文, Français

Photo by Jens Schott Knudsen via Flickr CC

Recent research shows that air quality affects the productivity of high-skilled workers. What does this mean for developing cities?

City governments invest a lot in job creation—they plan infrastructure, skills initiatives, and industry support with the goal to improve productivity and generate jobs and growth, especially in the high-skill sectors. Yet, there might be an important input to productivity that cities can pay more attention to: clean air.

Recent research suggests that a 10-unit increase in the air quality index decreases productivity by 0.35%. Seems marginal? This “productivity slow-down” costs the high-skill economy of China $2.2 billion per year for each additional 10 units of the air quality index.

The research in question studied the effect of air pollution on worker productivity in call centers in Shanghai and Nantong in China. The firm analyzed is Ctrip, one of the largest travel agencies in the country, employing more than 30,000 people. 50% of the workers’ pay is based on performance and the measures of productivity are very detailed and high frequency. The study concluded that there is a robust relationship between daily air pollution levels and worker productivity. On average, a 10-unit increase in the Air Quality Index (AQI) led to a 0.35% decline in the number of calls handled by a worker in a day at an AQI of 100. If we translate this to the entire Chinese high-skill industries, a 10-unit reduction of air pollution levels would increase the monetized value of improved productivity by $2.2 billion per year.

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