When looking around Google Earth in historical imagery, we have noticed an interesting trend with regards to the frequency of satellite imagery updates. It seems that Europe and the USA get significantly less satellite imagery than much of the rest of the world.
Although much of the less populated world has rather poor and infrequent coverage, some population centres seem to get very frequent updates. Here in Cape Town we have recently been getting several updates per month. We were recently looking at an area near Santos Dumont Airport, Rio de Janeiro, Brazil, and it has no less than 12 images so far in 2015. Even the relatively small town of Livingstone, Zambia has had two updates this year. Many large cities in the US and Europe, such as New York, San Francisco, Paris, Berlin and London still have 2014 imagery.
We have been wondering why this is. We will make a few guesses, but would welcome input from our readers too.
The USA and Europe are covered with high quality aerial imagery and thus new satellite imagery, which is of lower resolution, is usually relegated to ‘historical imagery’. Possibly Google, or the satellite imagery providers they source the imagery from, do not see the need for satellite imagery in those regions. Aerial imagery is typically more expensive to gather on a regular basis although we expect this to change in the future with as the cost of drones and high resolution cameras continues to fall.
Google tends to avoid satellite imagery with excessive cloud cover, and most notably, snow cover. So does this essentially mean that much of the Northern hemisphere will never get good coverage over the winter months?
Some of the recent Cape Town images can be explained as a ‘special event’ where imagery has been captured and put in Google Earth because it contains something interesting:
To see general trends up to October last year, this map is interesting. We hope Google updates it at some point to show more recent months.
About Timothy Whitehead
Timothy has been using Google Earth since 2004 when it was still called Keyhole before it was renamed Google Earth in 2005 and has been a huge fan ever since. He is a programmer working for Red Wing Aerobatx and lives in Cape Town, South Africa.
Interesting. I’m in the UK, in a marina that was built 4 years ago, & yet it still hasnt shown up on google earth / maps satellitre view.
Paul Lackey says
It would be nice if Google could put a little bit of effort into chipping away at the 15m Landsat only regions. Many places get dozens of updates a year, but places that have never been updated just stay that way year after year. You’d think that after ten years they could make it a priority to try to get a decent base layer of imagery for the whole planet.
The reason Google did this in the first place is because they were trying to compete with *mapping* software companies that you use to be able to find at the store.
Google probably realized how expensive it is to do this and this was when they focused on being an advertising company instead of polishing their search engine.
Killian Kelly says
The satellite view has been the same for the last 6years
will you ever update it for god sake