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Urban Growth and Megacities

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CDRC Maps. These maps help to visualize the world’s urban growth. Want to see what the world will look like in 40 years? These maps will help you comprehend the urban growth that is transforming countries worldwide. Photo by Charlie Ma/Flickr. We are living in the midst of the urban century. Though it is common knowledge that the world is urbanizing, it can be striking to visualize this growth on a map. This animation from Unicef maps countries’ urban populations from 1950 to 2050, and shows that urbanization is a global phenomenon set to continue for decades: Graphic by Unicef.

As seen in the animation, a number of African countries will go from less than 25% urban in 1950 to more than 75% urban in 2050. Image by Valerie Pieris. Asian countries are undergoing a century-long rural to urban migration. Some of this urban growth is concentrated in megacities According to the United Nations, there were ten megacities with ten million people or more in 1990. Graphic by Statista. Image by The Telegraph. Rapid growth is also happening in smaller cities. Bright lights, big cities.

The curse of urban sprawl: how cities grow, and why this has to change | Cities. I have just spent two days in Barcelona, one of the most densely populated urban settlements in the world. There are 103 road intersections per sq km – high compared to Brasilia’s 41 or Shanghai’s Pudong area, which has only 17. Yet despite these high densities, residents of Barcelona will tell you how profoundly liveable their city is.

Visitors are charmed by the pedestrianised streets that thread their way through a maze of buildings constructed over the centuries – between four and seven storeys high, on narrow streets leading to piazzas where people sit at cafe tables or under shady trees. Many residents walk or cycle to work, and public transport functions very well. For the first time in human history, most of us live in urban settlements – from megacities of 10-20 million, of which there were 28 in 2014, to medium-sized cities of 1-5 million (417 in 2014), and smaller settlements (525 of between 500,000 and one million people in 2014).

Metropolises expand and contract. Top 20 megacities by population - About us | Allianz. Urbanization. An urbanizing world Today, population growth largely means urban population growth. UN projections show the world’s rural population has already stopped growing, but the world can expect to add close to 1.5 billion urbanites in the next 15 years, and 3 billion by 2050. How the world meets the challenge of sustainable development will be intimately tied to this process. A world of opportunity For many people, cities represent a world of new opportunities, including jobs. The opportunities there extend beyond just jobs. The urbanization process – which is particularly pronounced in Africa and Asia, where much of the world’s population growth is taking place – is also an enormous opportunity for sustainability, if the right policies are put in place.

Inequality and vulnerability Still, the face of inequality is increasingly an urban one. Urban land is expanding much faster than urban population, a phenomenon known as urban sprawl. UNFPA at work. World’s population increasingly urban with more than half living in urban areas | UN DESA | United Nations Department of Economic and Social Affairs. Today, 54 per cent of the world’s population lives in urban areas, a proportion that is expected to increase to 66 per cent by 2050. Projections show that urbanization combined with the overall growth of the world’s population could add another 2.5 billion people to urban populations by 2050, with close to 90 percent of the increase concentrated in Asia and Africa, according to a new United Nations report launched today.

The 2014 revision of the World Urbanization Prospects by UN DESA’s Population Division notes that the largest urban growth will take place in India, China and Nigeria. These three countries will account for 37 per cent of the projected growth of the world’s urban population between 2014 and 2050. By 2050, India is projected to add 404 million urban dwellers, China 292 million and Nigeria 212 million.

With nearly 38 million people, Tokyo tops UN’s ranking of most populous cities followed by Delhi, Shanghai, Mexico City, São Paulo and Mumbai. Urban population boom poses massive challenges for Africa and Asia | Global development. Two-thirds of the world's population will live in cities by 2050, posing unique infrastructural challenges for African and Asian countries, where 90% of the growth is predicted to take place. The planet's urban population – which overtook the number of rural residents in 2010 – is likely to rise by about 2.5 billion to more than 6 billion people in less than 40 years, according to a UN report.

Africa and Asia "will face numerous challenges in meeting the needs of their growing urban populations, including for housing, infrastructure, transportation, energy and employment, as well as for basic services such as education and healthcare", it adds. Future development targets should focus on creating inclusive cities with adequate infrastructure and services for all residents, said John Wilmoth, director of the UN's population division. "Managing urban areas has become one of the most important development challenges of the 21st century," he said. Urban Population Map. Close Source United Nations, Department of Economic and Social Affairs (UNDESA), Population Division special updated estimates of urban population as of October 2011, consistent with World Population Prospects: The 2010 revision and World Urbanization Prospects: The 2009 revision.

Graphic presentation of data based on The Guardian, 27 July 2007. This map is stylized and based on an approximate scale. Notes Because of the cession in July 2011 of the Republic of South Sudan by the Republic of the Sudan, and its subsequent admission to the United Nations on 14 July 2011, data for the Sudan and South Sudan as separate States are not yet available. Data for China do not include Hong Kong and Macao, Special Administrative Regions of China. Data for France do not include French Guiana, Guadeloupe, Martinique, Mayotte and Reunion. Data for the Netherlands do not include the Netherlands Antilles. Data for the United States of America do not include Puerto Rico and United States Virgin Islands. The century of the city: top eight new megacities by 2025.

A brilliant new feature by the folks at Nature explains why this century is for the city. Called "The Century of the City," the feature outlines what's going on around the world -- and how it impacts the work of scientists and others. The feature is full of wonderful infographics, but also contains some starting facts. Among them: The United States is one of the few developed countries where cities continue to grow. Its urban population is predicted to increase by 15 percent to reach 308 million in 2025.Most urban growth in the U.S. isn't happening in big metro areas -- though New York City is predicted to reach 20.1 million people by 2025 -- but in smaller cities with less than a million people.Europe is stagnating.

But if you're into rankings, most interesting is the Top 10 list of megacities now -- and the cities that will join them in 2025. According to the report, the most populous megacities now are: Note the nations where these cities are located. Nature writes: Cities: The century of the city. The growth of megacities. Megacities, not nations, are the world’s dominant, enduring social structures — Quartz.

Back in June, NASA tested a booster for the most powerful rocket it has ever tried to build, the Space Launch System (SLS). The booster alone was more than 150 feet long, producing 3.6 million pounds of force, and reaching temperatures of nearly 6,000°F during a ground test in Promontory, Utah. The whole rocket is so expensive it will probably only fly twice in the next four years, if at all. A month later, in the Mojave Desert, a very different test took place, involving a prototype rocket just 12 feet long.

Built by a small company called Vector Space, it flew just a few thousand feet in the air, successfully demonstrating 3-D printed engine parts that will plug into a full-scale version just 42 feet long, not even a third of the size of one of SLS booster. If its designers are right, the Vector 1, as the small rocket is called, will fly hundreds of times before the SLS becomes operational, making the company a bundle along the way. Just a little lift It’s also a logistical hassle. Megacity life. Urban world: Mapping the economic power of cities. Six hundred cities—the City 600—are projected to generate more than 60 percent of global growth to 2025.

Within this group, companies need to adjust their strategy to include the 577 fast-growing “middleweight cities.” The urban world is shifting. Today only 600 urban centers generate about 60 percent of global GDP. While 600 cities will continue to account for the same share of global GDP in 2025, this group of 600 will have a very different membership. Over the next 15 years, the center of gravity of the urban world will move south and, even more decisively, east.

Open interactive popup Today, major urban areas in developed-regions are, without doubt, economic giants. But by 2025, one-third of these developed-market cities will no longer make the top 600; and one out of every 20 cities in emerging-markets is likely to see its rank drop out of the top 600. Companies looking for cities that will generate the most GDP growth will find another different list of potential urban hot spots.