Google Earth is probably best known for its huge collection of freely available satellite and aerial photos for places all around the world. Almost everyone who has access to a computer has given it a try – usually to look for their house, or to find out about a place where they want to take a vacation. The imagery database is really huge – millions of square kilometers – the equivalent of millions of 8 megapixel digital camera photos. Google hasn’t released the numbers, but we’re talking terabytes of images. But, what more people should take note of is the Google Earth “Layers“. Layers are available through an interface on the lower left of the Google Earth application. And there may be almost as much information in the layers as there are in the imagery!
Layers provide a wealth of information about our planet on a variety of subjects, and the layers are also a way for Google to share valuable contributions of information from many individuals, and organizations. The “Layers” are organized using a folder-like structure with categories at the high level, and you can open each folder to selectively view sub-layers. There is so much information here, it really just takes some time to explore and learn what is available. One thing you probably don’t want to do is turn on too many layers at once. I recommend turning a few layers on at a time at most, and turn them off when you are done. When you see a placemark icon for some information, make sure you try clicking on some of them. Some of these layers provide a lot of information in the descriptions of the placemarks.
For basic geographic information, I suggest you try the following:
- Terrain – I pretty much always keep this on. It is the 3D terrain you seen when you “tilt” your view and allows you to see things like mountain, valleys, and canyons.
- Roads – Google has detailed roads and streets for many countries including the US, Canada, much of Europe, Japan, and Brazil. More countries are becoming available every few months. As you zoom in you get more detail. From higher altitudes you’ll see fewer (or no) roads with this layer turned on.
- Borders and labels – this lets you see the outlines of countries, island names, coastlines, and administrative orders (states, counties, provinces, etc.). It even includes details on some disputed border regions. Again, as you zoom you may see more or less border information.
- Populated places – this is what shows the labels and locations for towns and cities world-wide – This layer is now found under the Borders and labels layer.
- Geographic features – this category contains sub-layers for things like locations of volcanoes, names of mountains, and water bodies. This layer folder is now found under the Places of Interest layer folder near the bottom of the list.
Another selection of the layers serve the purpose of highlighting points of interest if you are traveling. This is the same kind of information you get with a modern car navigation device (or GPS) for finding hotels, restaurants, etc. Examples of these kinds of layers in GE are: Dining, Lodging, Shopping and Services, Transportation, Travel and Tourism, Parks and Recreation, and Community Services. Like with the roads, Google has been steadily deploying this kind of information for more countries during the past several months.
All of the layers mentioned above are useful and important, but the really interesting layers are coming from a variety of sources not originally maintained or created by Google. Google recently released the “Geographic Web” layers which consist of a careful selection of useful information and pictures and references to web-based information on places all over the Earth. And, when that isn’t enough, you can turn to the Google Earth Community layers which show placemarks from posts made by hundreds of thousands of contributors about virtually everywhere on the Earth.
And finally, GE has “Featured Content” layers which highlight content from a variety of organizations. Here you will find information from Rumsey Historical Maps, National Geographic Magazine, Discovery Channel, European Space Agency, and even the United Nations. These layers highlight information of human interest, science, history, the environment, and even restaurant reviews.
If you haven’t explored the Layers in Google Earth, you are missing out on a world of information. And Google is continually adding and updating the layers. New and updated layer information comes out nearly every month.