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Imagine a big ship carrying 4,832 TEU's (twenty-foot containers) of very important cargo from Seattle to Japan. It's mid-point between Dutch Harbor, Alaska and Yokohama, Japan (can you find these places on the map?) crossing the Pacific Ocean when one of the crew members discovers that they are just finishing the last bit of peanut butter! How can this crew member alert someone in Yokohama that they will need to stock more peanut butter as soon as they arrive (because they can't live without their peanut butter and jelly sandwiches!!) It's actually pretty amazing technology (follow the diagram while reading the next paragraph).  The crew member types an email message with the request and sends it to someone in Yokohama. There are eight satellites circumnavigating the globe and the ship has its own satellite dish. So once the message has been sent, it flies around the atmosphere waiting to connect to one of the satellites. When the message is received by a satellite, it's instantly transmitted to IMC (International Maritime Corporation) in Connecticut where it's picked up and processed using their hi-tech satellite navigation technology. IMC then fires the processed messaged to the Internet Service Provider (ISP) where it's converted into the email language of the person in Yokohama receiving the message. This whole process only takes about 5 minutes! The ship sends messages twice a day, every 12 hours. All information is transmitted using two-way communication which means that messages can be sent and received at the same time. Until last year, only one-way transmission was possible. The ability to transmit two-way has cut the use and cost of the satellite in half (and at $7 per minute of use, this has meant significant savings!) How does an airplane communicate with the airport control tower and other airplanes? How about a NASA space shuttle? So, other than ordering peanut butter, what else does a container ship need to communicate to the outside world? A ship sends all of its payroll information via satellite so that each crew member can receive a signed payroll check as soon as they arrive at the last port on their rotation. A ship also communicates how much fuel its using and when it will arrive at the next port. Orders can be placed for things other than peanut butter such as charts used for navigating the vessel, parts or tools for repairing or maintaining the vessel, logbooks, pencils and, of course, other food, like bread and jelly! Ships also have an agreement to help the National Weather Service chart storm patterns. The barometer, air temperature, humidity, state of the sea, state of the sky, and condition of clouds are regularly logged and transmitted to the National Weather Service via email. You may be wondering if there are other ways for a ship to "talk to" the rest of the world. Other methods include using a fax machine, telephone or radio. A VHF radio is used, for example, in times of distress to issue a "mayday". Radio is also used on a regular basis to check in with the Coast Guard or other regulatory authorities at ports around the world, to listen to traffic reports, or to communicate with other vessels at sea. Do you know what VHF stands for? Can you find out why the word "mayday" is used? Communication at sea has come a long way since the days of steam going vessels in the mid-1800's. A ship could be at sea for months without communicating with anyone. They must have gone crazy without peanut butter sandwiches for that long! |
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