Understanding the Ocean Bottom in Google Map

This article has been edited to include comments from a knowledgeable anonymous reader and adjusted to reflect those comments.





In order to reduce the memory of loading this page I have moved the Visual Library of Undersea Terminology normally found at the bottom of this page to a separate page of it's own.
    


If we were to suck all the water out of the ocean it would look like this NOAA video.






So why doesn't the ocean bottom in Google Map look like the NOAA video?

The ocean bottom in Google Map is misleading depending on where you are searching. The reason why is the amount of detail is staggering, and would greatly increase the loading time of map, if they did not blur great sections of the ocean bottom. For example, the image below of some Pacific islands shows vast amounts of the ocean at a lesser level of detail while bubbling areas around islands in greater detail.






Yet, other islands have greater detail around them, but even here the amount of detail is still limited.





If you zoom in deep you can find areas like those below.

The North Atlantic Ridge.
The Southern Ocean, south-southwest of Australia. 

Note how the area in the middle are sharp with lots of detail, while other areas right next to it look blurred in a random pattern as though to reduce the amount of memory needed to load without greatly affecting the accuracy of what the area should look like. However, someone with knowledge of the subject left a comment on this article stating "The areas where there are stripes or patches of high detail adjacent to smoother bottom areas are ones where the high resolution sonar are available. It's not a Google smoothing issue. The vast majority of the sea floor is unmapped by sonar. The data for much of the sea floor came from satellite radar and/or gravity  measurements. 

Similarly, the long stretches of high-detail area are neither submersible travel routes nor Google glitches. They're trackline surveys from ships with sonar systems on them. Naturally they would only acquire data along the route they took. Again, it's the difference between having data and not having it.

Yes, they do use tiling and adjust the detail for zoom levels, because they are showing quite a bit of data.  But for the most part they don't show high detail in the sea floor because high detail of the sea floor does not exist.

That last paragraph seems somewhat contradictory to the first. He or she states that smoothing is not an issue, but states that Google does adjust the detail at various zoom levels due to the volume of data? Adjusting the detail and smoothing seem to me to be one and the same thing.Whether or not Google is intentionally smoothing the surface to limit the data, or working with what limited data there is, does not change the fact that the appearance of averaging the peaks and valleys smooths everything undersea. Anyway, I thank this anonymous person because he or she did add value to the discussion.

As you can see in the three Google Earth images below, everything seems so smooth, as though they were made of sand dunes. 



As the bottom image shows in the lower right corner, you can submerge down
34,533 feet into the Mariana Trench with this Google Earth KML file.
Be sure to turn on the oceans layer in order to travel underwater.





Now lets tackle those spiked submerged mountains in the NOAA video that look like the thin, very tall mountains. Ones like these:

#1: From the NOAA video at the top of the page. 

I have no idea where NOAA gets these spike mountains because the NOAA data in the Google images #2 and 3 below do not match the data in NOAA's video visual representation shown in image #1.

#2: Some of those very same mountains just off the continental self
on the East coast of the United States shown in Google Earth using
an image from Landstat, IBCAO and data from SIO,
NOAA, US Navy, NGA, GEBCO.

#3: Two of those very same mountains shown under water in Google Earth
using data from LDEO-Columbia, NSF, NOAA, SIO, NOAA, US Navy, NGA, GEBCO.

According to Wikipedia, the New England Seamount chain consists of over twenty extinct volcano peaks, many rising over 4,000 meters, or 13,123 feet, from the seabed which Google Earth indicates is -16,073 feet. The depth of the top of the nearby continental shelf in Google Earth,  at the edge, is only -428 feet. Yet in image #1, due to the perspective it uses, the spiked mountains look almost as high as the continental shelf when there is over 2,500 feet between the top of the continental shelf and the top of some of the seamounts. As I see it, the NOAA visualization in image #1 is questionable as to it's accuracy.

So where are the thin spiked mountains shown in NOAA image #1 that are not in the other images using NOAA data? I suspect some of that rounding in image #3 is due to averaging the data to reduce the amount of memory. However, I cannot see that one set of NOAA data would be so extreme as to create spiked mountains, while other NOAA provided data does not.

However, the knowledgeable anonymous person above stated "about the extreme spiked peaks in the NOAA video not seen in Google Earth. In the video, after the water is removed you can see that some extreme vertical exaggeration of the sea floor is implemented. This is to make the undersea features easier to discern. Pause the video at 0:06 and you will see that it more closely resembles what you see in Google Earth. The bottom line is that Google Earth is displaying what data it has available." 

I thank this anonymous person because this information should have been part of the video.

Below is the NOAA video at 0:06 seconds, it is displayed this way for a total of one second before the undersea mountains grow to spikes while rotating the planet at the same time, which gives a very distorted impression of actual undersea features:

It does look a lot more like Google Earth.

But at 0:23 seconds they reinforce this exaggeration with a graphic that further distorts reality. So we got 1 second of reality vs. 60 seconds of exaggeration without one comment in the video about it being an exaggeration for demonstration purposes. 




However, the undersea mountains in Google Earth still look a lot softer, more rounded, than the land based mountains shown in Google Map's terrain mode.



So instead of seeing sharp mountains like the above-ground one's
shown here above in Google Map terrain mode,
we get rounded submerged mountains like shown below.


Now lets take those extremely tall surmounts on the far right of image #1. I assume one of those is the Azores islands. So here is the tip of one of them seen from under water in Google Earth.


Where is the very tall spiked mountain to support this island?
 





With the exception of a few sunken ships like below that are near the surface, you don't see any sunken ships deep down. And, I have yet to find any ancient sunken cities.









Another thing that is interesting is that Google Map can show all the undersea details shown in my Google Map of Oceanic Trenches and Other Undersea Phenomena shown below, yet a Google Map cannot show the North and South Poles that can be seen in Google Earth. The reason why according to Wikipedia is that Google Map is based on a close variant of the Mercator projection that projects the poles at infinity. Thus, Google Map cannot show the poles and instead cuts off coverage at 85° north and south.






The North Pole, unlike the South Pole, is not a land mass. Instead it is covered with constantly shifting sea ice. Which for some reason does not show in Google Earth like it does around Antarctica. 


The North Pole as shown in Google Earth.

Thus, in Google Earth you can see things never seen before under the North Pole sea ice. Like this 78-mile long seamount and its 4-mile high cliff wall. The location of which is the yellow push pin in the image above.


89°15' 02.37" N, 175° 09' 57.56" E
4-mile high cliff wall within the seamount.
However, with the Catlin Arctic Survey KML file, shown below, you can see a simulated North Pole Ice Cap in Google Earth that can be used with MyReadingMapped's KML file of Fridtjof Nansen's "Fram" Arctic Adventure to see how the ship the Fram traveled Furthest North trapped in ice.


Image of the Catlin Arctic Survey's KML file.





Yet in Antarctica there is a sea ice anomaly in Google Map, that does not exist in Google Earth, where depending on whether you use satellite mode or terrain mode you either see sea ice or under the sea ice.


Google Map anomaly.

A similar result takes place with different zooms in satellite mode, areas that look like open sea zoomed out are covered in ice close up. If you try to zoom in on the Cold Seep (65° 26.5’ S, 61° 28’ Wat the Larson B Ice Shelf, you cannot zoom through the ice shelf itself in Google Earth, but you can zoom in at the ice shelf's edge. Unfortunately you cannot walk back under the ice cap because sea floor, at the top of the ridge shown below, is too close to the surface.

Detail of the Antarctic sea floor
at Larson B in Google Earth.
That same detail seen through the ocean surface
at the edge of the ice cap.






There is, however, an optical illusion in Google Earth regarding the sea level that can confuse being able to tell the difference between normal mountains and seamounts, or other undersea mountains, in Google Earth. It has to do with the surface water being semi-transparent and the angle and distance it is being viewed at. 


It is a matter of knowing the difference between this
snow covered mountain, seen entirely underwater,
which should not show the above-sea-level portion
of the mountain...

and this blue undersea mountain, or seamount...
and this mountain seen through the water
above sea level.




A Depth Gauge for understanding Oceans in Google Map:

-6,000 feet, -10,000 ft.
and -15,000 ft. (left to right)
It seemed to me that in order to understand ocean depths, that a depth gauge was needed for Google Map that contained samples of the various depths that could be determined by color and texture of the ocean bottom. So I made one.















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