A World Tangled in Wires...

What if...what if I were to tell you that there is a single cable that stretches all the way across the Atlantic Ocean? Would you be impressed? You might not be, if you are one of the few people who knows that the first Transatlantic Telegraph Cable was installed in the late 1850's. On the other hand, you might be even MORE impressed if you ARE one of those people, because that would demonstrate a healthy baseline level of enthusiasm for submarine telecommunications cables (the focus of today's post), which may not necessarily be present in all groups of people.

Again, I know, this topic is very literally "mundane" compared to lofty things such as the heliosphere, but as I hope to show you, submarine telecommunications cables are incredible AND we depend on them. I know for a FACT that my many MANY readers around the world rely on these relatively fragile pieces of cable for their monthly(?) dose of amazement. So now you may be asking, "who gave this crazy-person access to the internet?"...BUT I prefer to imagine that you are REALLY asking this question: "what, exactly, are we going to learn about these cables?" Well, first I will attempt to describe our dependence on ocean-spanning cables, then I will describe the cables themselves, and finally, I will show you how they are installed.

According to Wikipedia, as of 2006, only 1% of international communication overseas was mediated by satellites, and the rest, the rest being 99%, was carried out through undersea cables. Personally, I had always assumed that cell phone calls were carried via satellite...I assumed this because my cell phone is not connected to any wires, but clearly I was wrong. Another, similarly surprising statistic is one that I heard in a NOVA episode entitled "The Spy Factory": 80% of all communications from Asia (cell phone calls and emails but NOT postcards) is carried through fiber optic cables that span the Pacific Ocean and eventually lead to a "nondescript building in San Luis Obispo." Some cables are buried less than 6 feet underground where they come ashore. And the time it takes for a message to cross the Pacific Ocean? About 5 hundredths of a second!

In this map taken from an article in The Guardian, you can see the incredible web of wires that make it possible to rapidly transmit information almost anywhere in the world...except Antarctica. Antarctica is lonely.

Now you might expect that these cables are somewhat vulnerable...and they are. One of the most incredible things to me is that such a large percentage of our communications rely on submarine cables, and yet these lines of communication can be severed by things such as earthquakes, ship anchors and pirates. (!!!)

Because optical fibers themselves are fairly fragile, they are wrapped in a number of protective layers. The final diameter of a fiber optic cable is approximately 2.7 inches, and one meter of cable weighs 10 kilograms. Now, consider the SeaMeWe-3 submarine telecommunications cable, which extends from Norden, Germany to Keoje, South Korea and links 39 countries along the way. This cable is 39,000 kilometers in length, which means that the cable weighs 390,000,000 kilograms or 858,000,000 pounds. And to give you some perspective on this, I bench press about 1,000,000 pounds...so that's pretty heavy.

And finally, it would be my pleasure to share these two resources with you on the laying of submarine cables. The first is a video from the 1930s...so awesome:

And the second is a more recent movie, although the narration is slightly lacking compared to video number 1. It is, however more informative in terms of the actual process of laying the cable in the ground and the benefits of fiber optics as compared to coaxial cables. Notice how the cable is unrolled into the trench that is dug by the underwater plow: