Sunday 1 June 2008

Thematic Mapping Engine

It's time to introduce the Thematic Mapping Engine (TME). In my previous blog posts, I've shown various techniques of how geobrowsers can be used for thematic mapping. The goal has been to explore the possibilites and to make these techniques available to a wider audience. The Tematic Mapping Engine provides an easy-to-use web interface where you can create visually appealing maps on-the-fly.

So far only prism maps are supported, but other thematic mapping techniques will be added in the upcoming weeks. The engine returns a KMZ file that you can open in Google Earth or download to your computer. My primary data source is UNdata.

The above visualisation is generated by TME (download KMZ) and shows child mortaility in the world (UNdata).

The Thematic Mapping Engine is also an example of what you can achieve with open source tools and datasets in the public domain:

Try Thematic Mapping Engine

Please give your feedback by posting a comment below!


sephi said...

I cannot see where I can download the TME?

Bjørn Sandvik said...

Hi Joseph,

TME is not yet available for download.

Leszek Pawlowicz said...

Tried it, and I'm only seeing black as the color in all cases (no grading based on value). Prisms are being drawn, and do change height with time during time series, but they're very hard to see (black on black). Any ideas?

Bjørn Sandvik said...

Hi Leszek,

It seems to work here. Could you plese send me one of the KMZ files with errors?

Leszek Pawlowicz said...

Never mind - found the problem - probably a GE bug. I had the sun turned off; if I turn the sun on, and then off again, it displays correctly. If I resize my display with the sun off, it goes dark again, but turning the sun on and off again brings it back. Obvious ;-).

Nice app, BTW! Are you going to add the ability to import your own data?

Bjørn Sandvik said...

Yes, I plan to add the ability to add or import your own data in a future version of TME.

Anonymous said...

My congratulations, very nice work!
I used some of the UNData to create a kmz that shows the prevalence of HIV/AIDS at country level (see here)

Alex said...


An idea: you can integrate the new Google Earth API on the web, and see the KMZ on the fly on your web explorer (without GoogleEarth desktop application).

Bjørn Sandvik said...

Hi Alex,

Yes you can. See my comment on this page.

Simon Chapman said...

Your application is very useful -- I like your use of Ext JS.

Any chance you can add "Cellular mobile telephone subscribers (ITU/SYB50)" and "Cellular mobile telephone subscribers per 100 inhabitants (ITU estimates)" from UNdata to your list of data sources?

Anonymous said...

Bjørn --


FYI, I have a tool to make choropleth maps from user-provided data at
It is not as slick-looking as yours, though. :-)

(And Simon, you can make a KML file of the ITU data with Mapeteria if you don't want to waite for the polish of TME...)

Rich Treves said...

Hi Bjorn,

I like the technique, thematic maps are powerful tools and good to see you making it easier to produce them in GE. However, IMHO prism maps don't really work in GE, simple color differences works much better. For more detail see here


Bjørn Sandvik said...

Thanks for your feedback!

I'll add "Cellular mobile telephone subscribers" in the next version of TME ("released" one day this week)

Mapteria looks nice (I'll try it later). I especially like the possibility to visualise statistics on per capita or per area basis.

I think prism maps works very well in Google Earth. I'll write a blog post about "why 3d works" shortly.

earl singleton said...

I am an intern for the Institute for Creative Technology working on a project for Cultural Environmental Annotations. I stumbled onto this "Thematic Mapping Engine" and found it to be very intriguing. My concentration is in the area of ethnocultural characteristics with focus on dominant ethic cultures world wide. I am interested in learning more about embedding UNdata of ethical dominance into TME that would allow me to use this source as a plug-in to GE. Is this possible, and how do I do it?

Bjørn Sandvik said...

Hi Earl,

Your project sounds interesting. What are the geographical units of the "ethnical dominance" data?

If you have data on country level - I'm happy to include samples in my database, as long as the data can be used without restrictions (non-profit use).

earl singleton said...

I am new to the GE community so the geographical units I am not fully aware of as of yet. My focus is primarily in the Middle East in Iraq. I want to be able to show in GE the most dominant to least dominant of the Sunni, Shia, and Shi'ite religion due to their "geographical location" in that particular area. So if you could provide an example of what I describe, I would like to stay in contact with you to possibly learn more about how to embed this type of information across the GE community. This is totally a non-profit organization. We are working to aid the military for better strategical learning of environmental differences.


Bjørn Sandvik said...

I see. The geographical units will for sure not be countries - so the current version of TME will not help you. I plan to add support for different geographical units at a later stage.

You could try GMapCreator from CASA.

José Antonio Rocha said...

Absolutely amazing! Thx!

Anonymous said...

Hi Bjørn

cool tool. However when using danish æ,ø and å in description fields it's look strange. Do you plan to support all the unicode characters for your tool?

Bjørn Sandvik said...

Hei Søren,
Of course we need æ, ø and å. I thought the engine already supported unicode, - I'll have a closer look.

Anonymous said...

Hi, Bjorn

Congratulations !!

I'm a brazilian oceanographer and developed a application to spacialize sustainable development indicators using GD Library of PHP. It's so easy and useful !
I'll register my email at this site and wait anxixously the notice of the download opportunity !

I think that FOSS is a good solution to the problems of everybody ! So, I wish that You'll obtain sucess with this great initiative !!

Best regards,

Raquel Dezidério Souto.

Anonymous said...

Great work !
I'd like to use your tool and try to integrate in my own mapfish application. Would you share the source ? (

Anonymous said...

Any possibiltiy of putting in country borders in a timeline? So for example, you can see the Roman Empire expand, then collapse.

Bjørn Sandvik said...

You should be able to do that by wrapping the borders into different Folders and attach timestamps to the folders. It is actually what the Thematic Mapping Engine is doing, except that the borders are repeated for each time period.

Anonymous said...

But no one yet has put the historical borders together have they?

Anonymous said...

Hi it is wonderful

Hi i have a client jps application.
It produce tabular data.
Is it possible use your engine as server to produce thematic maps?
I wish to have a mush-up solution for Spatial OLAP.


(you can contact me at

Fabio Hideki Ono said...

I am amazed with the wonderful tool you have developed.

I am not familiar with PostGIS, MySQL and Php programming, but only VB, Access and Excel. I have some country statistics in MS-Excel and MS-Access that I would like to see ploted in a kml format. So I have 1 questions and 2 suggestion.
Question: Do you have the code in VB to read from shapefile and another code to create a KML file? Since I think you may not have it at hand, I have a suggestion.
Suggestions: The engine you developed is great, so why don't you develop a format in DBF or TXT/CSV, so that any user could upload a file (with country name/index and the statistics) to the engine, make all the setup and receive a nice KML file? It would be also lovely to have a stand-alone version of the engine to run it in a Windows environment.

Thank you in advance and congratulations for your nice blog.

Todd Gruben said...

What should I do to make the kml/kmz work in google maps? It loads fine in GE but when I upload the file, google maps complains about the kmz format

Anonymous said...

TME is the greatest GoogleEarth Mapping tool ever! Thank you so much for this work.

(geoffrey, geography teacher)

Web Mapping said...

Hi Bjorn,

Thak you so much for the amazing Blog. I learned lots of things on thematic maps thanks to you.
Any chance you release the source code of TME in the future ?

Bjørn Sandvik said...

The TME source code is now available at Google Code.

Davide Moraschi said...

It is good!
Very very very good job.
Can't wait for the ability to import our own data!

Anonymous said...

Friendly notice for you of a little bug I just found...
When I type a big number in the number of classes, it says 'engine failed'. (Actually, sometimes even you input 10, it says engine failed)..

Maybe you forgot some error check on the relationship between numOfDistinctValues and numOfDefinedClasses. If(numOfDistinctValues '<'numOfDefinedClasses), the situation is the same as unclassified.

You might want to take a look at this:)

But, I am still stuned by what you did!

Unknown said...

where i can download the TME??

sol said...

I love your idea, just wish that it would be more flexible with the data input - is there the possibility to include Cancer mortality from UNdata which I would love to visualise for a presentation at my university?



Bjørn Sandvik said...

Hi Sebastian,

You need to download the source to add your own data to TME. I'm working on a more flexible solution.

Bjørn said...

Thematic mapping is quite good. Invite you to see my regional kmzs at

Cassie said...

WOW! What a wonderful example. I showed this to my cartography class and the thematic mapping idea really "hit home" with the students. Got any more?

marcelo said...

the kml's gave me an error as bellow :


testing yet.

do you know what can it do ?

thanks for advance

congratulations about your tools

Anonymous said...

A wonderful resource. I am using it with teachers next week.

Anonymous said...

worked fine on google chrome last night on my personal standard computer. Does not generate preview here at school on firefox with the upgraded and more advanced computer.

et1011 said...

I use the engine as part of a GE exercise for my World Regional Geography courses, but unfortunately since January 2016 it hasn't been working. Any chance this engine will be back up and working again? It's such a great way to get students interested in Google Earth and mapping. Thanks for your work.
Emariana Widner
Kent State University
Ohio, U.S.A

Unknown said...

A great resource. I have noted that the Google Earth plugin fails to display a preview of a map showing mobile usage per 100 inhabitants yet the same map downloaded as a kmz file may be viewed using Google earth desktop application.

Esoibatxillerat said...

This is great, but I can't find wether is there a way to add more UN statistics, wich would be greater indeed!

Jack said...

where is the file for INTERNET USERS per 100 population for the year 2005? I want to download this file in google earth for my geography class on Wednesday. thanks. AND, I want to know where the screenshot of the Thematic Mapping Engine has gone where students can enter statistical indicators like population, Internet users, etc. etc. and enter the year, and the technique like choropleth map, bar , prism or proportional symbol and then colors, classes, time and display, and at the bottom of this site we could simply hit the "download" button and it would download onto google earth map as KMZ file. My students will be lost without this.
Please let me know soon. Thanks.
Dr. Jack Kinworthy-Lincoln, Nebraska USA