Send More Urban Planners

More human beings are moving to cities. You already know that. But according to new data (plus maps!) from the Global Rural Urban Mapping Project at Columbia University (yes, that acronym is GRUMP), the Earth looks even more citified than anyone thought. Mixing satellite data with stats from that Gridded Population of the World

2 minute read

April 5, 2005, 9:39 AM PDT

By Anonymous


More human beings are moving to cities. You already know that. But according to new data (plus maps!) from the Global Rural Urban Mapping Project at Columbia University (yes, that acronym is GRUMP), the Earth looks even more citified than anyone thought.



Mixing satellite data with stats from that Gridded Population of the World project I blogged about the other day (Jeez, these Columbia U. guys are all over this stuff, huh?), the GRUMP maps are the first-ever attempt to combine population size and the geographical extent of urban areas. Suck on that, United Nations Human Settlements Programme!



Cool results from the number-crunching:



GRUMP shows that 20% of the world's urban settlements have populations below 500,000. This is an important finding considering that the UN Population Division only reports on urban settlements of 500,000 inhabitants or more.



GRUMP data indicate that roughly 3% of the Earth's land surface is occupied by urban areas, an increase of at least 50% over previous estimates that urban areas occupied 1-2% of the Earth's total land area.



Coastal environments have much higher concentrations of urban land area (10%) and urban populations (65%) than other ecosystems. 



Far fewer Asian and African urban residents live in coastal and cultivated areas than residents of the Americas, Europe and Oceania, however, population densities in coastal cities of Asia and Africa are much greater than those on other continents.



GRUMP shows that approximately 7% of the world's population now resides in the largest mega-cities, whereas experts had previously estimated this number to be around 4%.



GRUMP has identified about 75,000 distinct settlements worldwide, but only 24,000 urban areasâ€"the result of many agglomerated urban settlements.





I know I'm harping on this, but superdense, super-poor, massive urban development on equatorial coasts practically begs for more kilodeath-scale tsunamis, quakes, etc (and destroys the environment while we wait).



(Spotted in the March 18 issue of Science, specifically this article [subscription req'd].)


portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

April 30, 2025 - Diana Ionescu

Close-up on Canadian flag with Canada Parliament building blurred in background.

Canada vs. Kamala: Whose Liberal Housing Platform Comes Out on Top?

As Canada votes for a new Prime Minister, what can America learn from the leading liberal candidate of its neighbor to the north?

April 28, 2025 - Benjamin Schneider

Hot air balloons rise over Downtown Boise with the State Capitol building visible amidst the high rises.

The Five Most-Changed American Cities

A ranking of population change, home values, and jobs highlights the nation’s most dynamic and most stagnant regions.

April 23, 2025 - GoodMigrations

People biking along beach path with moored ship in San Diego, California.

San Diego Adopts First Mobility Master Plan

The plan provides a comprehensive framework for making San Diego’s transportation network more multimodal, accessible, and sustainable.

May 2 - SD News

Sleeping in Public

Housing, Supportive Service Providers Brace for Federal Cuts

Organizations that provide housing assistance are tightening their purse strings and making plans for maintaining operations if federal funding dries up.

May 2 - KSL

Conductor walks down platform next to Amtrak train at station in San Jose, California.

Op-Ed: Why an Effective Passenger Rail Network Needs Government Involvement

An outdated rail network that privileges freight won’t be fixed by privatizing Amtrak.

May 2 - Streetsblog USA

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.

Senior Manager Operations, Urban Planning

New York City School Construction Authority

Building Inspector

Village of Glen Ellyn

Manager of Model Development

Central Transportation Planning Staff/Boston Region MPO

Write for Planetizen