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Credit: NASA/Goddard Space Flight Center

NASA satellites document the mysteries of underwater tides in captivating new video

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May 10, 2021, 3:30 PM EDT

The old proverb says that time and tide wait for no man, and that might be true, especially our planet's complex network of underwater tides hidden from human eyes.

Now in a new video from NASA's Goddard Space Flight Center, scientists and meteorologists can view these mysterious currents and their rhythms and flow thanks to years of revealing satellite imagery.

According to the new NASA simulation below, these types of Internal Tides, also called Internal Waves, can stretch hundreds of feet beneath the ocean surface, but only register as mere inches high when witnessed on the surface.

Despite these waves gyrating underwater, NASA weather satellites can observe and record the effects of these invisible tides from space, providing oceanographers with an interesting method by which to create maps and simulations of these fluctuation waters. 

As Sir Isaac Newton noted in the late 17th century, ocean tides are created by the gravitational tug of the Moon and the Sun. The low and high tides affect much more than just knowing when to go collecting seashells or strike out for a fishing trip, they are actually an intertwined system of long period waves that constantly cycle through the oceans as a consequence.

Over time they eventually arrive along coastlines and beaches where they comprise what we know as the natural ebb and flow of the Earth's oceans. 

It's strongly suggest that these underwater machinations could also aid in halting the staggering rate of global warming in our atmosphere, likely due to the formation of an intricate system of underwater waves known as Internal Tides, which can assist in shuffling heat into the ocean's interior. 

"Across a long swath of the North Pacific Ocean sits the Hawaiian Ridge, a massive underwater structure high enough in a few places to reach the ocean surface and form the islands of our 50th state," states the video's narrator. "The tidal currents that are generated by the moon’s gravitation impact the Hawaiian Ridge, causing deep dense water to be forced upward.

"Gravity and buoyancy forces then tug the water down and up again, creating oscillations. Those oscillations are internal waves. But since the waves oscillate at the tidal period, which is the time it takes for tides to complete one cycle, from high to low, and back to high again in roughly 12 hours, we call them Internal Tides."

Altimeters installed aboard orbiting satellites are able to detect and measure those minuscule surface waves caused by Internal Tides, something that NASA can employ to predict these gravitational rhythms using decades of recorded satellite data.

Credit: NASA/Goddard Space Flight Center

Our vast oceans display an incredible diversity of topographic features, including everything from hills, peaks, volcanoes, ridges, caves, and deep trenches. All of these geologic entities manifest sources of global Internal Tides and allowing for the tapestry of interconnected oceanic patterns portrayed in the Goddard Space Flight Center video above.

"Although Internal Tides might seem insignificant, being only a few inches on the ocean surface, they provide oceanographers with a unique way to map and study the much larger internal water motion," the video adds. "That water motion and subsequent mixing between warm shallow water and cold deeper water is thought to move heat from global warming of Earth’s atmosphere down into the ocean interior."