KML Workflow

KML can be produced from within Google Earth and exported to a text editor by clicking a folder you wish to export in the 'Places' column > right click > copy. The text can then be pasted into your favourite text editor and reloaded back later. This technique can be used to add some basic features that cannot be produced within Google Earth itself. There a are many features like this in Google Earth in this way such as regions (to help view lots of placemarks) and styles (controlling the look of labels, pop up balloons etc) but these are quite advanced and beyond the scope of these materials.

Here we look at two common and easy to implement features that require a little KML editing to produce.

 

Time Line

HowTo use timelines

By use of a timeline different elements in Google Earth will appear and disappear. This means that the position of an elephant in the jungle, the movement of a hurricane or the spread of bird flu can be shown as an animation in Google Earth. To use a timeline, produce elements as normal in Google Earth. Export the resulting KML and then for each element (placemark, polygon or overlay) insert a time tag, eg:

<TimeStamp> <when>1997</when> </TimeStamp>

 

There are two types of time in Google Earth: TimeStamp, as shown above is a moment in time, TimeSpan is a length of time. You should enter the tag so it goes in the right place in the placemark:

An 'object' is any element such as placemark, polygon etc. and starts and ends in the KML file with a tag, a placemark starts with <Placemark> and ends with </Placemark> 'Tag' is the construction like so: <my_tag>some text here</my_tag>, you need to fit the time tag (an example shown above) so that it fits with the diagram, thus if you had a placemark with a <StyleMap> tag (or any of the other tags listed above the time tags), the time tag should be placed immediatly below it. Time tags should be placed above any of the tags listed below them in the diagram.

Full details of how to write time tags including the way to write the time itself.

Once you have edited in your time tags, repaste the KML back to Google Earth. The timeline should appear if you click on the folder containing your time tags.

 

Snippet

In the Places panel Google Earth puts a the first couple of lines of your description below any element

The gray text can make the places column untidy and difficult to use, to get rid of it add a snippet tag, for instructions scroll down this resource.