Explore the Urban Observatory

Learn the basics of the Urban Observatory

First, you should become familiar with the Urban Observatory and the data it has available.

  1. Browse to the Urban Observatory Compare app and click Start Comparing.

    Urban Observatory Compare app

    The Urban Observatory opens with three maps under the Population Density heading. The default maps are of London, New York, and Tokyo. Each map has text beneath it, explaining the data.

    Population Density is the theme: the issue on which the maps are focusing. In this case, the maps show how many people live per unit of area.

  2. In the lower left corner of any of the maps, click Legend.


    The legend is the key to the map—it explains the map's symbols. In this case, the yellow areas have the highest population density. The dark red areas have the lowest.

  3. Click the legend again to close it.
  4. Use the navigation controls in the upper left corner of a map to zoom in and out. You can also use the wheel button on your mouse.


    When you zoom on one map, the other two maps zoom automatically. The maps are linked to stay at the same zoom level. That way, you can compare them more easily.

  5. Drag the mouse to pan any of the maps.


    Panning changes only the extent of the map with which you're working—the other maps don't move.

    Now it's time to see what kinds of data the Urban Observatory has available.

  6. At the top of the page, click Themes.


    The Themes pane displays the types of data you can view. The theme is currently set to Population Density, in the People category.

  7. Click Highway Access, under Movement.

    Highway Access theme

    The maps change to reflect the new theme.

  8. Open the legend and read the bottom text.

    The maps depict areas within 10 minutes of a highway exit, with bright yellow areas being even closer. Tokyo does not have data available for this theme. The Urban Observatory has plenty of cities to explore; you're not limited to just these three.

  9. At the top of the page, click Cities.


    An alphabetical list of cities appears, which you can scroll through by clicking the arrows on either side of the tab. Cities with names in white have data available for the selected theme. Cities with names in gray do not have data available.

    Since you're looking at highway access, you should add a city famous for its highways: Los Angeles.

  10. Click Los Angeles from the list of cities.

    Los Angeles replaces Tokyo as the city on the third panel.

  11. Use the zoom and pan functions to explore the three maps.

    Highway Access theme: Los Angeles

    What patterns do you see? In New York and Los Angeles, many highways run through the center of the city, but in London, highways are only found in the outer regions. Why do you think this is? London is much older than New York and Los Angeles—could this have something to do with it?

  12. Change the theme to New Development, under Systems.

    New Development theme

    The New Development theme shows areas of the city that were developed recently (between 1990 and 2000). It is a good indicator of how a city is growing.

    New York does not have data for this theme, so you should swap it out.

  13. Replace New York with the city of Mumbai.

    New Development theme: Mumbai

    Mumbai is the most populated city in India. Unlike cities in the United States or the United Kingdom, cities in India are typically experiencing rapid development.

    Compare the three cities. Which is experiencing the most development? Where are the cities focusing their development?

    Although larger than Mumbai in terms of area, London and Los Angeles appear to have minimal development, with most development occurring far away from the city center. Mumbai, however, appears to be undergoing a lot more development closer to the center of the city. These trends could reflect the amount of growth each city is experiencing, with Mumbai experiencing the most.

  14. Change the theme to ParkScore, under Public.

    ParkScore theme

    ParkScore is a much different type of theme than the demographic and developmental themes you explored earlier. It maps the location of parks and areas with park access. It also assigns each city a ParkScore based on park quality, accessibility, and size. You can find the ParkScore in the text under the map.

    Los Angeles has a ParkScore of 45 (out of 100)—not too great a score! Neither London nor Mumbai has ParkScore data, so currently you have nothing to compare.

  15. Replace London and Mumbai with cities that have ParkScore data. Compare those cities to Los Angeles. Do they have better ParkScores, or worse? Which city has the highest overall ParkScore, and which has the lowest?

    You can find definitive answers to these questions because ParkScore is quantified as a number. But as you saw with the New Development and Highway Access themes, answers are not always easily quantifiable. The Urban Observatory is a great starting place for asking spatial questions, but to answer them, you often need to investigate the issue more deeply.

    You know how the Urban Observatory works and what kinds of data are available. Your next task is to put that knowledge to use by asking a spatial question of your own.

Ask your own spatial question

Asking questions is the first step of the process toward solving spatial problems. To answer your question, you must perform analysis, interpret the results, make a decision, and finally share your findings. In this section, you will explore the Urban Observatory to come up with a question, which you can then answer on your own or challenge your friends to answer.

Look through the available themes and cities and craft a question. If you have difficulty, thinking about the following may be a good start:

  • What are the differences between cities?
  • Where do those differences occur?
  • Why do these differences exist?
  • Are the trends local, regional, or global?
  • What can be done about these trends? Does something need to be done at all?

Once you come up with your question, you’ve completed the first step of the spatial problem solving approach.

After you ask a question, your goal will be to decide what procedure is necessary for the next stage of the process, performing the analysis. But that's for another lesson. Learning how to ask the right questions is the most fundamental step in the process. Without a question, none of the other steps can even exist. The Urban Observatory serves as a tool for discovering differences and asking questions about them. A few example questions include the following:

  • How does a high senior population correspond to a high youth population?
  • What historic, cultural, or geographic factors cause Berlin to have a significantly higher percentage of open space than Tokyo?
  • What are the predominant occupations of different urban areas?
  • Does Sao Paulo have more traffic congestion than Santiago? Why? Is traffic related to highway access?
  • Does Chicago deserve its nickname of the Windy City or is there another city with even stronger winds?

The possibilities for questions—and answers—are limitless. Remember, no question is a bad question, but some provide more insight into our world than others.

In this lesson, you learned how to use the Urban Observatory to compare cities from around the world. You then used your knowledge to ask your own spatial question. How do you answer that question? ArcGIS offers a variety of analytical tools that can help, and the other lessons on Learn ArcGIS explain the spatial problem-solving process in more detail.

You can find more lessons in the Learn ArcGIS Lesson Gallery.