What happens when you send a Styrofoam cup WAY down into the ocean? When it comes back, does it look different? Why? This is the classic science experiment you can do at sea (when you have access to the really deep water, and the really long cables). You have heard us talk about the CTD onboard our ship, which we have sent down dozens of time to take measurements and samples of the water, at all different depths, and all along our route. So let me tell you again what CTD stands for – conductivity, temperature, depth. And let’s concentrate on the “D” in CTD. Depth in water really means pressure. As you go down further into the water, you have the weight and pressure of all that water around you. The deeper you go, the higher the pressure. We decided to run this experiment, and see first-hand what happens when a Styrofoam cup feels that pressure. Although we didn’t have actual Styrofoam cups for everyone, we improvised by dividing some Styrofoam containers we had onboard (like the kind you get when you order take-out food). Styrofoam is an ideal material for this kind of experiment, because of its low density and, by definition, “foamy” and easily-compressed structure. Each of us designed our own piece and it was sent down in a mesh bag along with the CTD – 600meters deep. Here’s how it all “went down” (or not quite)…
Here are Svetlana and Ekaterina, designing their Styrofoam pieces.
The “before” picture of some of our pieces (There is a red marker in the photo for scale): If you look closely you can see that I did one for me and another in honor of our new Patricia and Phillip Frost Museum of Science, currently being built in downtown Miami!
The CTD helps us do our experiment – all the way to 600meters (about 0.4miles) deep (this was the deepest CTD cast that we had left to do at the time).
Here I am bringing back the results of the experiment – almost like bringing back a sunken treasure!
The moment of truth: Antoine and Ioana check the pieces, to discover that it is not quite the results that we had hoped for…
Here’s the “after” picture (with the same red marker, for scale): you can see that even the pressure at a depth of 600meters couldn’t compress our pieces into miniature Styrofoam pieces (You can see a very small change, which we pretty much expected, but we were still hoping to see a little more…)
For comparison, Florence, one of the students in the Summer School onboard showed us what happened on a previous expedition in which she participated. In the photo below, taken by a colleague of Florence’s on that expedition, you can see an ordinary Styrofoam cup on the right. On the left is an ordinary Styrofoam cup – that has been placed on a CTD and sent down more than 2000meters (1.3miles). That’s some water pressure!