Current position of the SSV Corwith Cramer. Click on the vessel to view position history. Use the tools, top right, to change the map style or view data layers.
SEA Currents: SSV Corwith Cramer
Be the Gimbal
12° 38.361’ N x 061° 21.820’ W
Weather: 3/8ths cloud cover, Cumulonimbus; Wind ENE at 7-10 kts; Sail Plan: 4 Lowers
In the morning we picked up anchor outside of Petit Rameau and motored on over to an anchorage outside Canouan to clear customs. After that, we motored away from Canouan and set the sails for the first time in several days – It’s great to be underway again. Not too much is happening now, so let me tell you a tale about science.
Picture this: It’s a beautiful evening in lab, and you’re hard at work taking measurements. Suddenly you find it difficult to walk to the sink just a few feet away. Why aren’t your feet working? It must be that your leg muscles simply didn’t get the message, and you decide to push just a bit harder to traverse the floor. At that exact moment, the floor shifts, and suddenly it’s far easier than you ever wished to travel forwards. With the combined force of your overzealous leg muscles and the rolling floor, you’re propelled across the lab as if you’re a stuntman on strings. Your waist meets the edge of the sink with a thud, and it feels like you’ve hit the wall in a bumper car as your torso flies forward over a sieve full of zooplankton. This is what it’s like to do science aboard the Corwith Cramer, and I absolutely love it.
Hannah and I are in the lab with our science officer, Farley, and we’re processing samples from the recent science deployments. It’s around 2am, so sometimes it feels like we’re still dreaming, but the seas and the ship conspire to keep us awake. The good news is that my sink-assisted stop has put me conveniently close to the graduated cylinder and the zooplankton, both of which I’ll be using to take biovolume measurements. What’s a biovolume you ask? What we really care about is biomass, which gives us insight into productivity in the portions of the ocean we sample, but weighing things with an analytical balance on a rolling ship is sort of like trying to weigh yourself on a bathroom scale while jumping up and down. Sure, you could get a ballpark measurement, but that’s not good enough for science. Fortunately, a landlocked scientist has gone to the trouble of equating biomass measurements with biovolume measurements, which are much easier on a ship.
My sink-assisted stop has brought me conveniently close to the zooplankton sieve. I fill the nearby graduated cylinder to 20 mL with seawater and proceed to scoop up all the “zoop goop” (don’t worry, it’s a technical term) and plop it into the cylinder. The water level climbs higher as it fills with zooplankton. Once our entire sample is safely inside, all that’s left is to read off the water level. The difference between the initial 20 mL of seawater and my personally certified precision measurement will give us our total biovolume, and from there it’s only a hop skip and a jump to get approximate biomass. The ship rolls back and forth making it near impossible to read the cylinder, and as just as things begin to look bleak, I remember Farley’s words of wisdom: “Be a human gimbal”. With a renewed sense of hope and vigor, I pinch the cylinder at the top between my thumb and forefinger, suspending it in the air with the lightest of pressure, allowing the graduated cylinder to swing with the motion of the ocean. The water ceases it’s angry, spiteful sloshing and I’m able to read the biovolume measurement. We aren’t in CHEM 7L anymore, Toto.
All dramatic descriptions aside, I’m loving my time aboard the Cramer, and I’m constantly amazed that my waking hours are spent amongst the wind, sea and sky. The clouds and stars are magnificent, and I’ve had loads of fun surveying the reef here in Tobago Cays. It’s been an adventure like no other, and I look forward to once again becoming a human pinball in the lab once we’re underway again. If the predicted weather comes true, I’d say this story will repeat itself sometime soon.