Mapping Time in ArcGIS 10

One of the features of ArcGIS 10.x is the ability to “time-enable” your data in ArcMap. Visualizing how data changes over time provides opportunities for powerful, more in-depth analysis. If you’re using ArcGIS 9.3, you can visualize temporal change by creating an animation. You can still create animations at version 10, but there’s an easy alternative as well.

The example below shows how to use visualize piracy-related incidents that occurred between March, 2007 and February, 2009 in and around the Gulf of Aden.

Click to enlargeThe map document shown on the right includes the World Topographic Map basemap from ArcGIS Online for geographic context, and an Incidents point layer that represents locations where pirate attacks occurred. The Incidents data is a set of Anti-Shipping Activity Messages that was downloaded as a shapefile from the National Geospatial-Intelligence Agency (NGA) Maritime Safety Information portal and loaded into a file geodatabase feature class.

The points on the map reveal the number of attacks that occurred during the time period, and you can see the incident distribution. By time-enabling the incidents, however, you can visualize the progression of the attacks and find out whether there were “clusters within the cluster.”

Click to enlarge

The Incidents layer contains a DateOfOcc attribute, which stores the date (mmddyyyy) that each attack occurred. In order to time-enable a layer, you must have one (or more) fields that stores time data (such as dates). A best practice is to store time data in a date field, but numeric or text fields will also work.

Set Time Properties

At ArcGIS 10.x, the ArcMap Layer Properties dialog box has a Time tab. So the first step to visualizing the time component of a layer is to simply open the dialog box and click the Time tab. Then follow the steps below:

  • Check the box in the upper-left to “Enable time on this layer.”
  • In the Layer Time drop-down list, choose ”Each feature has a single time field.”
    • For this example, this is the appropriate setting because the attribute table has only one time field. Sometimes, there are two fields that store time data; for example, StartDate and EndDate.
      Click to enlarge
  • For Time Field, choose the field in the layer that contains your time data. In this case, it’s DateOfOcc.
  • For Time Step Interval, you can manually set the interval or you can let the software calculate an interval based on your data. In this example, 2 days was specified.
  • At the bottom of the dialog box, check the box to “Display data cumulatively.”

These settings will draw incidents for each two-day increment and keep earlier incidents displayed as succeeding incidents draw—allowing you to see the pattern of occurrence over the two years spanned by the data.

Time-Enable the Map

  • Click OK to apply the layer’s time properties, then click the button on the Tools toolbar to open the Time Slider window.
  • Click to enlargeClick the “Enable time on map” button in the upper-left corner of the Time Slider window.
    • After clicking this button, only the data associated with the start time displays on the map.
  • Click the Play button to see the incidents display in order based on their date of occurrence.

This time visualization reveals that in 2007 there were fewer incidents of piracy, they were much more spread out, and they did not appear to be consistently in close proximity to land. By early 2009, there were significantly more incidents, and they appear to be far more concentrated in the Gulf of Aden, specifically on the Yemen side of the gulf.

The change in incident distribution could be due to an attempt by ships to avoid the Somali Coast. NGA Special Warning Number 123 advises mariners to remain at least 200 nautical miles distant from the Somali Coast.

Sharing Time Visualizations

The time properties are saved with the map document. You can share the time visualization by sharing the map document. But what if the people you want to share with don’t have ArcMap?

From the Time Slider window, you can quickly export a time-enabled map to an .AVI file, which can be viewed using the free Windows Media Player.

Watch the video Watch the video

Knowing where things occur is the cornerstone of GIS analysis. You have to know where before you can hypothesize why. Another dimension to GIS analysis is when. Knowing where and when things occur means you can not only visualize patterns, but how patterns have evolved over time. With this information, you gain a deeper understanding of your data and can better model and predict future patterns.

Esri Educational Specialist Ryan Otto contributed to this post.

SuzanneB

About SuzanneB

Suzanne is a Maryland native with a degree in English Literature who enjoys writing about Esri technology and other topics. She works with Esri Training Services in Redlands, California.
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14 Comments

  1. nnhong says:

    Great post, above, SuzanneB, is there a way to stop the video, at the full coverage? the example-video above stops at where all points are gone………thanks a lot,Nan Hongnnhong@monsanto.com

  2. SuzanneB SuzanneB says:

    I think you may be referring to a video player issue. When viewing the exported video file (.AVI) with Windows Media Player, I’ve found the video automatically closes at the end. In QuickTime, the video stops with the last frame still showing (i.e., all features showing at the end of the time extent). Try QuickTime if you haven’t already.

  3. nsavar says:

    Hello Suzanne,In my dataset, I have start and stop times for each feature. I’m unclear about Start-Time-Field and End-Time-Field on the Layer Properties > Time Tab. How does that relate to the Time Slider window tab “Time Extent”? What I would like to do is show features as they come online and go offline, year by year. I have different stores that open and close at different years. For each year, I would like all features that are open to cumulatively show on the map. I cannot figure out the right combination of options. thank you for your help. if you would rather take this offline, my email is nsavar@uic.edu–nina.

    • SuzanneB SuzanneB says:

      Hi Nina,It sounds like you need to set the time step interval in the Layer Properties dialog to one year, assuming you’re only interested in viewing stores by year. The time step interval controls how many features display on the map in each sequence of the animation–you could step through by week or month if you wanted to compare activity level within each year (to see which month had the most store openings, for example). In the Time Slider window, you set a time extent to play just a subset of your data in the animation (stores open in a specific year or group of years).

  4. scottlew says:

    Hi Suzanne,The time slider window seems to have disappeared from my screen.  I am using ArcGIS 10.1 on a laptop and I go back and forth with using the laptop screen only and dual monitors conneted to a docking station without viewing the laptop screen.  Any tips on how to find the time slider window and get it back on screen?  Thanks!

  5. sleusink says:

    Hi Suzanne,Can you use time slider within ArcReader and published maps?  Or is the only way to share these visualizations through ArcMap or exporting videos?  Thanks!  Stephanie.

    • SuzanneB SuzanneB says:

      Hi Stephanie, the time slider window is not available in ArcReader and published map files (.PMFs). For more info on working with temporal data in ArcGIS, you may want to check out the Temporal Maps group on ArcGIS Online.

  6. je1188 says:

    Hi Suzanne! I was wondering if you could help me figure out how to make objects disappear from my map. I am trying to simulate the founding and abandonment of a number of sites, and would like objects to both appear (founding date) and disappear (date of abandonment). I am able to achieve the former, but not the latter. Any suggestions? Thanks!

    • SuzanneB SuzanneB says:

      Hi, assuming your founding date values and abandonment date values are stored in separate fields, make sure you have specified that your features are stored in two time fields and select the correct start time field and end time field (in the Layer Properties Time tab). Uncheck the option to display data cumulatively. This should allow features to disappear from the time slider window on their abandonment date.

  7. je1188 says:

    Hi Suzanne,Sorry for the delayed reply and thanks for the help. It appears that I had confused the ‘Tracking Analyst’ with the ‘Time Slider,’ which was why I couldn’t get end dates. I’ve done as you said, and I think that it ultimately will work. I have, however, run into a new problem. In the ‘Time Slider Options’ menu, under the ‘Time Extent’ tab, I cannot change the start and end time. They are automatically set to 01/01/0001. For this reason, when I try to run the time slider, none of my items appear. When I try to change the times, in the ‘Time Extent’ tab, I receive the following error message:”Time entered is not within the valid time extent. Please enter time in the correct format and with in full time extent of the map.” I have tried every possible setting in the drop-down menu ‘Restrict full time extent to’, but this does not make any differenceIn case this is of any help, in my layer file, the start and end time fields are formatted as YYYY-MM-DD. There are several cells with dates listed as <Null> and they are the only ones that appear on the map when I enable time. The rest do not appear.Please let me know if you need any further information here and thanks so much for the help!