The Weather Notebook: The Ocean Floor

The Ocean Floor
Listen in RealAudio
Email Your Comments

Dave Thurlow, Host

Hi I'm Dave Thurlow from the Mount Washington Observatory and this is the Weather Notebook. When Geology and Oceanography join forces, some ancient and vital information comes to the surface. I spoke with Oceanographer Dave Gallo from the Woods Hole Oceanographic Institute:

DSV Alvin is a manned deep sea submersible vehicle capable of reaching depths of 14,764 feet. Alvin has logged over 3000 dives throughout three decades of service. Some of those dives participated in sediment core sampling retrieval. Dan Fornari Photo
DG: There's a story in the sea and that story is preserved in the sediments of the sea floor and in the rocks beneath the sediments of the sea floor.

That story reveals a few billion years of the Earth's climatic history. One of the scientists who figured out how to get that story was Charlie Hollister, a geologist at Woods Hole too. Sadly, he passed away this summer - but he left behind quite a legacy.

DG: What Charlie was able to do was not only ask questions about the sediments, what can they tell me about past climates, tectonics, volcanoes and earthquakes; but he was able to develop the kinds of tools to go out and collect the clues that he needed to put together that puzzle.

Hollister developed a long coring system, which takes a narrow tube and drops it down about 37,000 feet to the bottom of the ocean - kind of like dropping a skinny pole out of an airplane at cruising altitude. The tube extracts sediment from about 10 feet into the ocean floor -- a watery graveyard of broken bits of shells and animals all made from the environment at that particular moment in time. From a scientist's point of view, the sediment is recorded tape actually revealing past climates from the evidence in the ocean floor.

DG: By doing what Charlie Hollister did, by looking to the past through the sediment recorded at the bottom of the sea floor, is the best way to understand where the planet has come from, where it is now and where it is going.

The Weather Notebook is underwritten by Subaru and the National Science Foundation.