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.
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.
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…”
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