By Edwin Schiele
October 25, 1998. Flashback! Its October 6, day 11 of our voyage. Steve Gegg, master of data processing, utters these words. "We are accumulating sonar data at a rate that would fill 125 floppy disks every 15 minutes."
Steve of course was only making an educated guess, but lets assume his estimate is accurate. The DSL 120 generated sonar data for 323 hours. That would be enough data to fill 161,500 floppy disks. A box of 10 floppy disks is 32 cubic inches, so 16,150 boxes takes up approximately 300 cubic feet of space.
That is only a small portion of the computer storage space we need. The cameras on ARGO II took approximately 240 hours of video and 29,320 still shots. All of the sonar data are then processed, maps are generated on the computers, still images are combined to create mosaics of larger images, and all of the data must be duplicated at least once. Then of course there are all of the navigation and vehicle attitude data, and, of course, the pictures used for this web page. We are talking millions of floppy disks worth of information.
Fortunately, we have other ways to store the data, so the number of floppy disks on board is small. (And contrary to rumors being spread around the ship, Steves mother does not provide all of the disks.) Instead, the data are stored on cartridges of 8 mm data tape and 4 mm digital audio tape. Each one of these tape cartridges, which are about the size of the tapes you play on cassette recorders, stores up to five gigabytes of information. That amount of information would fill 5,000 floppy disks. The videos from ARGO II are stored on HI-8 video tapes. Each of these tapes contains two hours of footage.
The cruise ends. We have thousands of gigabytes worth of data. What happens to it next? Some of the data will be put on the Internet. All the data storage tapes, video tapes, and paper records will go to Woods Hole Oceanographic Institution. The data then becomes available to the researchers on the cruise. Each of the principle researchers on the cruise will then want to analyze the parts of data that interest them so that they can publish their findings. Copies of the data also get placed in the WHOI archives.
Now lets say that you are a researcher who wants to look at some of the ARGO videos. You stick in a tape and watch pillow lavas slowly drift across the screen. You tire of that, so pop in another tape. More pillow lavas, only they are moving across the screen at a different angle. You cant learn much just by looking at the tapes. Data without context are useless, so you turn to the cruise report.
If you were to tour the ship during these final days, you would find scientists assuming the tortured writers pose. The body is slightly hunched. One hand is in the vicinity of the computer keyboard. The other is on the forehead. The eyes stare blankly either at the few words written on the computer screen, a piece of paper on the desk next to the computer, or (my preferred direction) somewhere into deep space. The pose is frequently broken for bathroom breaks, to fetch soda or candy, or to check the progress of the latest wax core. They are writing chapters for the cruise report.
The cruise report contains every piece of information about every aspect of the voyage, including the objectives of the cruise, the people who participated and their interests, how, where, and why the data were collected, where the data are stored, and how many bowls of ice cream each person ate for lunch.
The cruise report provides meaning to those pillow lavas dancing across the monitor. You can learn how the images were taken. You know where to go to find the depth and position of these pillow lavas and to find out how close they are to a crater. You know that the reason that the logging information is so confusing is because the logger ate too much ice cream at lunch.
Now you know what happens to all the data that we accumulate. But what about the thousands of pounds of rocks we are bringing on board?