The Descent

Witness this Incredible Event on Film!

You can read a book with the ambient light at 500 feet!

The color change will amaze anyone that free falls down a sub sea mountain range. A most spectacular site. The color changes form a light blue at one hundred feet to a real blue at two hundred. But at three hundred feet the preception is that things start to get darker and amazingly by five hundred feet light again! So light in fact that you can read a book!

Why ? The laws of physics. As we descend into the ocean, colors start to be absorbed by the plankton. The first color to go is red, followed by orange, yellow, green, blue then indigo and violet. Collectively we call this white light. The last color to go is violet which during the day can penatrate and glow down to a depth of 1000ft. We as pilots rely heavily on this physical event to navigate. In fact we will navigate the sub at one thousand feet without lights or sonar and arrive safely at our objective.I had the honor of takening down a space shuttle commander. Tom Hendrik a four time commander on board Columbia and Atlantis said that the this area 800 feet looked like the surface of the moon!

The deep sea is considered to begin beneath the photic zone. This an area that plant life ceases due to lack of sunlight and photosynthetic capabilities. This is important because all creatures from this point fall into the animal kingdom. The deep sea makes up 98% of the earths biosphere. It is hard to pinpoint but estimates are that there are some 600 million unidentified species in the abyss.

It not unusual to see a creature in the mid water column (area of water between the surface and the bottom). In fact it is teaming with life. Plankton mostly. Plankton is defined as anything that relies on the ocean currents for transport and it is broken up into animal plankton called zooplankton and plant plankton called phytoplankton. These are the basis of the food chain in the ocean, a concept that must be understood to truly appreciate the abyss.

The 600 foot level is a special zone due to its thermocline.This layer of water whose temperature and density are dramatically different create a barrier for sound to bounce off of its interface. Sometimes sound can travel for many miles bouncing off this zone. The SOSUS (sound surveillance system) which are microphones on the bottom of the worlds oceans can detect geological and biological sounds. One sound from a biologic was heard in California and emanated from Chili! These microphones were not always built for science, but were used to aid the hunter killer submarines track the boomers during the cold war. Pilots experienced many types of noises but only one time did it become dangerous. A British war ship entering the waters off the Cayman Islands was using active sonar. The frequency was at such a pitch at 600 feet that it hurt ones body and ears. It was so bad in fact we considered aborting the dive.

Current plays an important role in the handling of the mini subs in the deep. There is much more current in the shallower depths from 100 to 300 feet than in the deeper depths.Although on a routine dive to a shipwreck at 800 feet I saw the aftermath of what most certainly was a benthic storm. Large objects had moved on the shipwreck and a new fresh silt lay where clean decks where once visible. Oceanogreaphers say that the event could have been an eddy current that had spun off the Gulf Stream like a tornado spun off a huricane!

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