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.



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.














Now for some basic undersea terminology:

The following definitions are from Wikipedia and the images are from my Google Map of Oceanic Trenches and Other Undersea Phenomena:



Continental Shelfs: The extended perimeter of each continent and associated coastal plain.  Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas (known as shelf seas) and gulfs, and was similarly submerged during other interglacial periods.

See where the pictured continental shelf is...







Submarine Canyons: A steep-sided valley cut into the sea floor of the continental slope, sometimes extending well onto the continental shelf. Some submarine canyons are found as extensions to large rivers; however most of them have no such association.

See where the pictured Submarine Canyon is...
















Oceanic Basins: Hydrologically, oceanic basins include the flanking continental shelves and shallow, epeiric seas. 

See where the pictured Oceanic Basin is... 









Abyssal Plains: An underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 meters. (9,842 feet to 19,685 feet) 

See where the pictured Abyssal Plain is...








Seamounts: A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface (sea level), and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from theseafloor to 1,000-4,000 metres (3,000-13,000 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 metres (3,281 ft) above the seafloor.

See where the pictured Seamount is...




Oceanic Plateaus: A large, relatively flat submarine region that rises well above the level of the ambient seabed. While many oceanic plateaus are composed of continental crust, and often form a step interrupting the continental slope, some plateaus are undersea remnants of large igneous provinces.

See where the pictured Oceanic Plateau is...










Mid-Ocean Ridges: Underwater mountain system that consists of various mountain ranges (chains), typically having a valley known as a rift running along its spine, formed by plate tectonics.

See where the pictured Mid-Ocean Ridge is...











Oceanic Trenches: Hemispheric-scale long but narrow topographic depressions of the sea floor. They are also the deepest parts of the ocean floor. Up to 35,000 feet or more.

See where the pictured Oceanic Trench is...



















Undersea Earthquake Zones:

Page two of the Oceanic Trenches and Other Undersea Phenomena map, has examples of zones where undersea earthquakes occurred that had an impact on whale strandings. Note how these two examples align with cracks, ridges or other undersea features.

See where the pictured Undersea Earthquake is...












Hydrothermal Vents: A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots.


See where hydrothermal vents are. 















Hydrothermal Vents and Cold Seeps.
Cold Seep: A cold seep (sometimes called a cold vent) is an area of the ocean floor where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs, often in the form of a brine pool. "Cold" does not mean temperature of the seepage is lower than the surrounding sea water. On the contrary, its temperature is often slightly higher. Cold seeps constitute a biome supporting several endemic species.

See where cold seeps are. 






Whales: There are two whales that can be seen in Google Map. 



See where the pictured whales are.. 











Google Map of the Topography of the Thermohaline Circulation of the Oceans: Zoom in on the oceanic topographical features that shape the ocean's Thermohaline Circulation in this Google Map



Google Map of the topography of



Google Map of the El Niño Zone:

Zoom in on everything you want to
know about 
the El Niño Zone in
this Google Map.







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