What a day. Today was, by far, the busiest one I’ve had. The reason is quite simple: we did two casts, which meant double the preparation and double the number of samples to analyze. Most of our casts are sent to 1000m but we occasionally want to sample even deeper water to measure the chemical, physical, and biological properties of the water that makes up a lot of the deep ocean. I can imagine you saying “Wait a second. Isn’t water just water?” The answer to that is, not quite. Although all water has the same basic chemical makeup (H2O), its other properties can vary quite a bit. By testing water at various depths, we can see how its properties change.
Besides being busy, however, today was also quite fun – we decorated Styrofoam cups!
Think about what happens when you swim down in the ocean – if you go deep enough, you feel the pressure around you change (your ears may pop or feel clogged). This is because water pressure increases with depth. We use this to our advantage. When we send Styrofoam cups to 4000m, it drastically alters their appearance.
Here is a picture of my cup when I colored it:
And now here is a picture after it came back up (next to a blank of it its original size for reference):
There’s a huge difference in the cup’s size!
Here’s your challenge – Why does the water pressure at 4000m shrink the cup? Don’t worry about answering this now, we’ll discuss this when I come visit in June (but feel free to message me via Edmodo with your ideas!).
Tomorrow is certainly going to be interesting. We’ve been sailing in some rough weather for the past few hours and will continue to do so. Therefore, we won’t have a pre-dawn cast with the Niskins – it’s just too dangerous to be out on deck. We’re completely safe inside though!
Until next time,