Google vs ESA: sign o’ the times

Posted by William M. Connolley on September 14, 2007
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I happened to be visiting ESA’s page, and found its image of the week, which is Rotterdam. So I thought I’d look at googles version and – its much better. And of course you can scroll in to far better detail.

And conveniently embed it here, so lets have a play:
View Larger Map

[Update: several people have complained that this post is unfair, and/or silly, because it compares the incomparable: while google looks pretty, there are lots of exciting things you can do with ESA imagery. That misses my point, which was: once upon a time, not very long ago, an ESA image like this really would have been interesting. Nowadays it is but a commonplace. ESA will, no doubt, continue to provide an image of the week because its on someones task list; but unless they can add some value by interpreting it, why would anyone bother look? -W]

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Comments

  1. #1 Luboš Motl
    2007/09/14

    It’s by far the most civilized and human-converted landscape I’ve seen in my life. Flying above the Netherlands is always fascinating. This is how generic pieces of Earth may look like in 2300.

  2. #2 leo
    2007/09/14

    What is shown is an area just south of Rotterdam. To see Rotterdam, scroll up or view larger map; the green arrow points to the center of the city.

  3. #3 Janne
    2007/09/14

    Comparing apples and pears. The ESA image is one image, selected as being visually interesting. Google map is not. Put another way, which one would you rather have framed and on a wall?

  4. #4 J.
    2007/09/14

    Usually I enjoy reading your blog … but this post of yours is really silly.

    Earth observation satellite operators (like ESA, NASA, DigitalGlobe, etc.) provide individual images that can be used for many different purposes. High resolution vs. low resolution, optical vs. microwave vs. thermal, spectral channels in the visible, near-IR, SWIR, atmospheric absorption bands, etc etc etc ad infinitum. If you need an image of Greenland or Timbuktu on a particular date, from a particular type of sensor, you can get one.

    Google provides a completely different service. They assimilate other people’s imagery and use it to make pretty pictures. They don’t provide multiple dates of imagery, they don’t provide radiometrically calibrated imagery, they don’t provide spectral information outside the 400-700 nm range, they don’t provide consistent imagery from place to place, they don’t provide image metadata. There is no way to use Google Maps’ imagery to study transient events like a hurricane, a forest fire, an algae bloom, or whatever.

    The ESA image that you are dissing is an active microwave image. You could use this image for things that Google’s imagery is totally unsuited for — e.g., calculating soil moisture in unvegetated fields or biomass in a forest plot.

  5. #5 Alastair B. McDonald
    2007/09/14

    Why don’t you post a comment instead of whinging.

    Why don’t you say that if the Greenland ice sheet melts then those pictures will be all sea?

    [Large amounts of that area is already below sea level. Could the Dutch build an extra 5m of sea walls in 500 years? Very likely -W]

    Why don’t you say that if the Arctic sea ice disappears then the Greenland ice sheet is sure to follow?

    [Because it oversimplifies the matter. Timescales are important. If greenland doesn't go for 500 years then... we have a long time -W]

    Why don’t you say that the Greenland ice sheet is already losing mass and even if CO2 levels stop rising the melt will continue?

    [Becaause its actual contribution to SLR is currently rather small -W]

    Why don’t you say that this year the the Arctic sea ice not only broke the 5 M sq km. barrier, it now seems sea to be breaking the 4 M sq km barrier?

    [Plenty of other people are excited about the Arctic ice, there is no need for me to. Rather less heralded, Antarctic ice seems to have hit a record high -W]

    Why don’t you say that if the Arctic sea ice sheet disappears then the Greenland ice sheet will not take long to follow?

    [Because you've just said that twice? -W]

    Why are you moaning and not facing reality?

    [Oh but I am facing reality, rather than an over-hyped version of it -W]

  6. #6 Eli Rabett
    2007/09/15

    For the same reason that people look at the astronomy picture of the day. To learn something, to be amazed, to enjoy.

  7. #7 Adam
    2007/09/15

    Google have only recently managed to get a decent resolution coverage of the UK, which was very frustrating for a while. The other issue with Google is that many/some of their (non US) images are out of date.

    Take for example Sheffield: http://tinyurl.com/2kx6bn
    The high-rise buildings in the centre of this image, of Sheffield station, were demolished a couple of years ago and they’ve completely revamped the area in front of that. So this image is at least two years out of date, so it shows that you can’t always rely on Google. I have no knowledge of Rotterdam so have no idea if it’s out of date, but I wouldn’t rely on it to be current.