As opposed to the ocean exploration expeditions of the Nineteenth Century, modern expeditions tend to be focused on understanding and studying specific phenomena or studying a particular geographic location in detail. The suite of tools available to do this would amaze the ocean explorers of yesteryear. As opposed to wireline sounding machines that would obtain widely spaced depths, there are multi-beam sounding instruments and sidescan sonars that map the seafloor in incredible detail. Problems of navigation have virtually disappeared as scientists are able to determine the position of their ship and instruments to within a few meters on the surface of the Earth by means of the Global Positioning System. As compared to using the imagination to reconstruct environments from a few specimens dredged from deep, the manned submersibles and remotely operated vehicles used today allow scientists to see creatures of the deep and seafloor environments directly through viewing ports or through the lenses of amazing camera systems. And instrument packages that can continuously measure temperature, conductivity, and various other physical parameters throughout the oceanic water column replace the instruments of the the past that relied on widely spaced samples to develop a rudimentary knowledge of the nature of the waters of the ocean.
But with all of these advances, the excitement of discovery remains. New species are found, undersea volcanoes are observed erupting, unknown behaviors of long-known creatures are observed, and, most importantly, we humans are becoming increasingly aware of our reliance on and responsibility for the oceans as the moderator of our climate, producer of much of the oxygen we breathe, and ultimate source of much life on Earth.