This is the second in a series of posts on Google Earth data sizes. Yesterday we had a look at 3D imagery and also compared it to the aerial imagery in the same location. Today we are looking a the different types of 2D imagery. As we have seen in the past, Google Earth has imagery in a wide variety of resolutions.
Just that tiny white square has 1.5 GB of aerial imagery.
We tested using regions of 100 square kilometres with a camera height of 1 km, except for the regions with aerial imagery, where we set the camera hight to 300 m to try and ensure the imagery loaded completely.
|Location||Imagery type||Size in MB|
|Germany||Aerial imagery – Geobasis-DE/BKG||1,532|
|United Kingdom||Aerial imagery – Google||2,002|
|Japan||Aerial imagery – Google||1,930|
|South Africa||Satellite imagery – CNES / Astrum||247|
|Canada||Satellite imagery – DigitalGlobe||368|
|Algeria||Satellite imagery – Cnes / Spot Image||20|
|Papua New Guinea||Satellite imagery – Landsat||16|
|Pacific Ocean near Hawaii||Ocean floor detailed||12|
|South Atlantic Ocean||Ocean floor minimal detail||8|
|Zoomed out view of Google Earth||3|
As you can see, the amount of data used by different imagery types varies dramatically. The ocean floor figures may be a little inaccurate as they include the 3 MB or so that Google Earth downloads just on logging in to show the earth when zoomed out. We initially thought the German aerial imagery was higher resolution than in other parts of the world, but the results suggest that is not the case.
The country of Germany is approximately 350,000 square kilometres. It would take about 525 GB to store all the aerial imagery in the default view for the whole country. Historical imagery adds a whole new dimension, which we will look at in our next post in the series.
Samples from the locations we tested. Note the scale on each image.
To see the locations we tested with in Google Earth, download this KML file.