The Google globe looks a lot nicer today, at least from afar, because the faux 3D bathymetry painted onto the ocean surface just got a lot more detailed. It’s now a lot clearer, for example, that while the Mediterranean is a deep sea, the Yellow Sea/West Sea a shallow sea.
And it is now also a lot clearer how islands connect below the surface of the sea, for example with the Cayman Islands and Cuba.
And finally, in many places the ocean floor appears to be rendered in as detailed a fashion as is currently available — you can see clear evidence of where bathymetric surveys were taken and of survey ship paths in the Southern Ocean, where high resolution mapping of the ocean floor is otherwise still scarce:
But what this layer also hints at is that the mooted and hoped-for true 3D ocean landscape is likely not arriving anytime soon to Google Earth. A true bathymetry DEM for the globe would have been a real feat, but instead we’ll be looking at a 2D rendering of it for a while yet.
(BTW, In November 2008 GEBCO released a 1-minute resolution global grid to the public as a free download, with 2D viewing software (for Windows). I suspect this is the same data as is now viewable in Google Earth in 2D (though a 30 arcsecond resolution dataset was due to be releasedin “early 2009″ as well). To view it, start here on the GEBCO site; the actual registering and downloading is done from the British Oceanographic Data Centre (BODC). The complete dataset is a 274MB download. There is software that lets you view this data in 3D as well, but I believe you have to buy it.)
Some have not been so happy with what Google hath taken away with this update: Commenters on Frank Taylor’s Google Earth Blog report that pacific atolls previously rendered at the global base resolution of 15m per pixel have now gone missing wholesale.
And another commenter, who knows the bathymetry of the Catalan coast quite well, reports that the data sports four fictitious sea mounds there. Indeed, an overlay for Google Earth lets you do a direct comparison:
That’s likely the result of some erroneous original data being processed and ultimately rendered as a undersea peak.
Meanwhile,Barry Hunter isn’t impressed with how the bathymetry visualization melds with the satellite imagery along the coastlines. And Kurt’s Weblog notes that discrete contour lines are visible on some parts of the US coastline.
I went looking for some of my own favorite small islands, and noticed that they too have gone missing: The most remote island on Earth, Bouvetøya, has disappeared…
And so have a number of other sub-Antarctic islands, such as the Balleny Islands:
These islands are uninhabited, yes, but Sturge Island alone is 30km in length. To be fair, none of the other online mapping services have anything useful on the Ballenys, but that is no reason to lose them in Google Earth:-)