If you’ve ever stared out at the ocean on a stormy day, you can see how the dark skies make the ocean appear grayer than it would on a clear afternoon. Part of the color of the ocean is determined by the incoming light — but the color is also affected by different properties of the water itself.
To understand the ocean’s color, we use lots of different optical instruments. One of these is called the Ocean Color Profiler, or OCP. When dropped over the back of the ship, this sort of dart-shaped array sinks down below the surface and records both how much light coming down from above and how much is reflecting up from below. Several of our instruments, including the VPR (described in my last post) measure how much light is scattered by particles in the water, which affects the clarity of the water — more particles mean a hazier ocean.
The reason we care about the color of the ocean isn’t just because it’s nice to look at. The color and clarity of the ocean tell scientists how ‘productive’ those waters are — how much life is growing below the surface. So while the impossibly blue waters we’ve been sailing through (water color ‘like an Instagram filter,’ one scientist commented to me) are beautiful, it also means that there are few plankton growing and supporting a food chain here. The unfortunate (for us!) consequence of this is that we’ve seen very little marine life beyond the sea birds and flying fish. We were hoping for whales or dolphins as we passed through French Polynesia early this week, but alas, no signs of life.
We did, however, draw within a few miles of the island of Maupiti on Monday afternoon. We got so close that you could even pick out individual palm trees growing on landscape. At the same time, we could the dramatic landscape of Bora Bora silhouetted against the horizon off the other side of the ship. Many of us spent hours on deck as we passed by the islands — the first land we’ve seen since we left Hawaii, and likely the last land we’ll see until we get to Tahiti at the end of February!
As we draw closer to our starting point, the ship is getting noticeably emptier. We will be working around-the-clock when science begins, so everyone is trying to adjust their sleep schedules accordingly. For most people, this has meant going to sleep progressively later or waking up progressively earlier and cutting out either breakfast or dinner. I count myself lucky in that my assigned shift allows me to continue on pretty much a normal schedule (and fit in all three meals!).
On the bright side, this gives the remaining diners a little bit of extra time to finish our meals — we’ve been operating under an “eat it and beat it” policy in the mess, in order to get everyone fed during mealtimes. The downside to splitting the shifts, especially when there are already fewer people on board than there would usually be, is that opportunities for things like ping pong tournaments or cribbage games (one of the favorite card games of sea-goers) are limited.
In response to Peter K.’s question of a few days ago: Barney did not bring his mini trombone on this cruise but he claims that his full-sized one is on board. He has yet to perform for us, though, so I remain skeptical. I also know for a fact that there are at least three ukuleles and two guitars on board, but I haven’t heard anyone but myself playing. Maybe once the masks come off, people will be more inclined…
Giuliana Viglione is a journalist and science communicator who has joined Senior Research Scientist Barney Balch’s research cruise to study the impact of coccolithophores in the Southern Ocean. On board the ship, she’ll be helping the team carry out experiments, document the research cruise, and conduct educational outreach with students across the country. She can be reached at giuliana.at.sea@gmail.com.