Sunday, September 27, 2009
Top to Bottom
Compared to what we know about the terrestrial Earth -- or even about other planets -- our knowledge of the ocean depths is embarrassingly limited. It's an issue, ultimately, of accessibility. The deep oceans, however beautiful and inviting, are a notoriously dangerous place for a land-lubbing species such as ourselves, with the risks increasing the farther we descend. What we can't easily get to, we also can't study.
The most obvious problem is oxygen. Fish and other water-dwelling organisms are equipped to access the oxygen dissolved in water. We are obviously not fish, and we can't breathe -- naturally, that is -- underwater. Divers holding their breath (free divers), many of whom have developed extraordinary control over their heart rate and other body functions, can stay underwater for minutes at a time and dive more than 100 meters deep. (Kathy Svitil)
One big problem is pressure.. Check out this DEEP SEA SIMULATOR
You need the free FLASH plug-in
Beneath the world's oceans lie rugged mountains, active volcanoes, vast plateaus and almost bottomless trenches. The deepest ocean trenches could easily swallow up the tallest mountains on land . Think you know the tallest mountain on Earth?
The real answer might surprise you.
The REAL deep dive record though was set by Piccard and Walsh on January 23, 1960, when the Trieste reached the bottom of the Challenger Deep in the Pacific Ocean's Marianas Trench -- 35,810 feet -- that will likely never be bested. No one has even tried. In fact, in the nearly 40 years since, no person has plunged to within 10,000 feet of the record.
Students: for an excellent review resource features in the Benthic zone/ocean floor/ocean bottom
DIVE IN HERE To check your understanding try this QUICK QUIZ
Perhaps the best way to grasp the magnitude of our unseen Earth is to "imagine" what our planet would look like without the oceans.
For an even more "in depth look" Check out National Geographic Drain the Ocean
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at 2:56 PM