On March 8, Malaysia Airlines Flight 370 took off from Kuala Lumpur en route to Beijing, and, two hours later, simply vanished. How was it possible that a huge airplane with hundreds on board could disappear so completely? Well, Flight 370 disappeared over water -- and it turns out that once you get even a little bit away from land, you go out of reach of the seemingly omnipresent network of monitoring systems that we take for granted.
That's starting to change, somewhat, as our technology gains a toehold in the 70% of our planet covered with water. This slideshow takes a look at some of these advances, from tools to track fish to boats improved by landlubber technologists.