A motion in Google ocean

Did you ever look at Google’s digital Earth model and notice something missing? Like 70% of Earth’s topography, for instance? The seafloor shown there is a kind of “shadow topography”. It’s satellite derived. Fortunately for us, everything in Google Earth with an elevation less than zero is about to get some sweeet emotion.

As it stands, Google Earth’s ocean is a blended product of Landsat imagery and a state-of-the-art bathymetry model that is, well, sooo last century.

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Deep water features in Google Earth are a satellite-derived reflection of 1) sea surface topography, 2) Earth’s gravity, and 3) old fashioned lead-line ship soundings. Satellites can ‘see’ seamounts and mid-ocean ridges because massive submarine features kind of ‘bend’ gravity to reveal themselves to orbital instruments (Smith and Sandwell 1997). Ship soundings are used as anchor points for the digital model.

This was state of the art when it debuted in Science in 1997, and is still widely useful for exploration, but what we see in Google’s ocean is a mere shadow or what’s really there down below. Believe me. I spent two years working with satellite-derived bathymetry to determine seamount resolution. Seamounts are under-represented in size and complexity, but satellites detect them neatly (Etnoyer 2005), so no complaints.

According to Cnet’s story Google diving into 3D mapping…, soon we’ll all be able to get in a submarine and fly-through canyons to see the underwater world in high resolution the way marine scientists do. The new product will be an assimilation of improved satellite altimetry, multibeam echosounder technology, and other declassified information to allow unprecedented insight to the ocean realm. Add some photos to Panoramio and videos to YouTube and you got yourself the next generation in telepresence technology.

If you’re not convinced Google’s ocean needs improvement, check out two examples. The first is shown above, an image of Monterey Canyon from Google Ocean on the left, and then a multibeam image from Craig’s home base at Monterey Bay Aquarium Research Institute. The one on the left is 4km resolution at best. The satellite product can see anything larger than about two New York City blocks. The multibeam product on the right can see anything larger than a refrigerator (2 m) or a swimming pool (25 m) depending on the source.

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Next, an image of Saba Bank in the Caribbean Netherlands Antilles. Saba Bank is a large submerged feature about 20m deep, bigger than St Maarten, Saba, and St. Eustatius put together. The image on the left is from Google Earth. The Landsat image on the right is from a project I’ve been working on for the Saba Conservation Foundation and Conservation International. The boundaries of the image on the right match the red rectangle on the left.

Notice the complex habitat structure. Dark color is algae, but coral on the southeast rim, and light color is sand and pavement. We’re working to document the marine biodiversity of this atoll so tankers could please stop dropping large damaging anchors where they shouldn’t. It’s just one of many marine research and conservation goals that can be accomplished in this new age of geospatial awareness. Think of the possibilities.

Scientists predict researchers and NGO’s will be flocking to the project like gulls to a turtle hatching.

“Google will basically just provide the field and then everyone will come flocking to it,” predicted Stephen P. Miller, head of the Geological Data Center at the Scripps Institution of Oceanography. “There will be peer pressure to encourage people to get their data out there.”

A slew of projects are in the works including some very novel efforts, like geo-spatial documentaries hosted by National Geographic explorers, and some traditional enterprises like integrating geo-referenced photo and video from exploration vehicles like the DSV Alvin manned submersible, for instance.

If you can’t wait for Google Ocean, Marine Geoscience Data System has a jump on the action. The Google distribution model being what it is, the ultimate utility of Google Ocean will rest with its user group, those enlisting in the Ocean Revolution.

I see a geo-referenced layer of DSN stories and adventures narrated in photos and videos by Dr. Craig McClain and Kevin Zelnio in my mind here now. Anyone out there looking for an internship? We need you. How fast can you type “Dear Google Ocean, Please send money to…”

References:

Etnoyer, P (2005) Seamount resolution in satellite-derived bathymetry, Geochem. Geophys. Geosyst., 6, Q03004, doi:10.1029/2004GC000833.

Smith, WHF & DT Sandwell (1997) Global Sea Floor Topography from Satellite Altimetry and Ship Depth Soundings. Science 26, Vol. 277, no. 5334, pp. 1956 – 1962 doi:10.1126/science.277.5334.1956

Peter Etnoyer (406 Posts)

PhD candidate at Texas A&M University- Corpus Christi and doctoral fellow Harte Research Institute for Gulf of Mexico Studies.





11 comments on “A motion in Google ocean
  1. That will be so sweet. (But no replacement for manned and remote operated visits.)

    The Atlantic sea mounts each look so boring in Google Earth, but… they are pretty complex. Nowhere near as complex and exciting as the multibeam soundings reveal them to be. It will help convey that complexity having higher resolution bathymetry in a public tool that 1st graders can use.

  2. Definitely, Tai. If you look closely at the Google Earth image of Saba Bank, you’ll see my Panoramio photos of dive sites not listed in any book, or any map.

  3. Is that first shot one of Santa Cruz / Monterey Bay? Looks very familiar to me (especially being a marine biology student in santa cruz)…

  4. That’s right. Monterey Canyon is smack in the middle of Monterey Bay between Santa Cruz and Monterey.

  5. Well I better recognize that one! Been in that bay for 5 years now, and been spending my time researching it!

  6. 30m would be much shorter than a football field.

    Do you have an idea of the coverage of the multibeam data?

  7. Collecting bathymetry information is frightfully expensive.
    Only large governments of nations with busy ports, and
    large oil companies, do it. The US OCS, NGA, and the UKHO,
    have the best tools and processes but we only have the resources to survey a few hundred square miles each year.

    When Google Earth finally gets around to accepting and displaying negative elevations (not only for the sea floor but for places like Death Valley or the Dead Sea area),
    so that our information could be more easily and widely viewed, that would free up precious resources which we could apply to doing more surveying.

    This is of course just my opinion, I can’t help what my management does or says.

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