August 5, 2018
It should be no surprise that moorings became my style of oceanography. I came to Alaska in 1993 to learn physical oceanography, specifically to use acoustics to establish identify changes in ocean temperature. But the vagaries of grant funding put me onto polynya research off the distant east coast of Greenland—the sort of research where bottom-anchored current meter moorings were the only means to collect year-long data under seasonal ice.
I’ve never been one to lose sleep risking hardware for a chance to get a better picture of the landscape of things. In truth, I barely bat an eyelid, once I’ve assessed the risks. I’ve flown a drone close over a chaotic river during spring break-up, and on weekly, pre-programmed flight-paths over a hillside forest to record the change of the seasons. I’ve left a $5000-dollar camera alone on an ice sheet before we drove this very ship at said ice, aiming not quite at the camera. The ship was going to ram the ice anyway as part of its commissioning trials.
I wanted to get video of the ship breaking ice—from a vantage not the ship. Turns out we were a couple weeks into the cruise, I had some redundancy at hand, and the Captain was, for the mere thought of the footage, more than willing to have someone go, safety permitting, back on the ice afterwards to retrieve the camera. Offering up the camera was easy, and perhaps not so different from how any oceanographer adds their piece of hardware to a deployed CTD. The cage, the rosette, the regular suite of hardware is going down 100 meters, 200 meters anyway. Strapping another scientific instrument, or even just a GoPro to the rig only makes the adventure more-so.
I’ve put pocket cameras and even GoPros on model rockets so I could photograph the staging of the engines. A calculated risk, the cost of the hardware weighed against the value of the thrill and the satiation of my curiosity. It’s all curiosity and thrills in the end. Some thrills add a little more to the wealth of human knowledge.
I did lose one rocket. It got caught up in a tree near the field. I never got to see the eight or nine in-flight photographs the cannibalized $20-camera caught on the way up and the way down, as it drifted too far east. After a couple winters hanging by the parachute, one of the neighbors or a squirrel pulled it down. Or maybe the branch broke. Birch trees do that, inexplicably, like a stainless-steel shackle can be eaten by seawater. Moorings strung up in the water column—sometimes they get caught in a fisherman’s net. Sometimes they get put back again in a different spot. Note that one of the top-most instruments is a locator beacon It has a phone to call for help. Once the machine surfaces, it starts emailing invested parties. No, there is no reward for finding one.
The idea, regardless of the hardware, is to capture a ‘picture’ of a place we cannot go ourselves, or not without even greater risk and greater cost. There is no cheaper way to experience riding a chunk of ice as it crashes down river, spinning and jerking and diving under other ice and whole trees caught in the flow. There’s always the possibility our machines will lose power and drop to the bottom of the boiling river. But we’re not going to see what’s on Mars without investing billions in machines that yes, could go wrong.
So, it’s not such a bad deal, cost-wise, putting a mooring in 48 meters of ocean, weighing it down with a railcar wheel and making it stand near vertical with a series of carefully engineered floats. To get any data back at all, we place an acoustic release about 3 meters above the wheel. The ones we’re using are twin, bright yellow canisters looped together at the bottom with a chain. There are two because one of them might fail. Both of them might fail. It’s possible neither will fail except that anything left in the ocean for a time can get fouled with detritus and barnacles. Things fail. Things fall. Things grow on surfaces. Things are mud down there.
We grow the mooring on the ship’s working deck. It’s a string of instruments whose weights and floats are calculated to be buoyant above the anchor. The pieces are settled into the water gently, and then we drop it as a piece.
The instruments vary from mooring to mooring. On the rockets, I engineered a mirror to allow a camera to look downward on take-off but then hinge out of the way then the parachute deployed. The camera could look straight out the window as it drifted down.
Mooring instruments also look at different things in the water. They come alive periodically, moving a sample collection into position. Today, we aimed to collect three mornings of the Chukchi Ecosystem Observatory, all of them unique. CEO I’s deepest instrument sampled water and plankton every two weeks and then preserved the samples for eventual retrieval. Kate’s passive acoustic receiver sat 9 meters off bottom and listened for marine mammals. We hope it recorded “everything.” Then, at 12 meters off the bottom lay the 33-inch flotation buoy, on top, the Acoustic Doppler Current Profiler (ADCP). Its four red “eyes” use sound to measure current speed and even wave-height at the ocean surface. On the side of the buoy, a MicroCAT recorded temperature, salinity, and pressure. A year’s worth of data rides on the acoustic releases listening and responding a year after they go into the deep. The batteries are rated for two.
It’s no frivolous thing to put a mooring in the water and expect you can collect it a year later, or even a couple weeks later. The cost of a mooring is high, not taking into account the cost of the ship to get on station, twice. But the data is rich. A ship collects a large amount of data moment to moment, but only where the ship is, moment to moment. If you want to gather data from one particular location miles out in an ocean, moorings, despite the left-out-in-the-cold risks, are a better option. The ship gets us there and gets us back again.
The Sikuliaq arrives where CEO I was last seen. Pete dials up the mooring’s ENABLE code on the acoustic transmitter and sends the command to the release, 48 meters below and some two-hundred or so meters to port—we think. We know we are close. Ethan listens as the release pings back. It says it’s a hundred and some meters away. Pete dials in the RELEASE code to tell the mooring to surface. Now, it shouldn’t take long. But it seems to. Watching from the working deck, there’s no sign of the large syntactic float risen to the surface. And we’re still watching to port when word comes down. The mooring has come up on the starboard side of the ship. I asked Ethan yesterday, when we launched the glider, what the risks were the glider would re-surface directly under the landing craft, or the ship. He just nodded and said the chances were very small. I agreed with him. But still.
We snagged the mooring with a hook and brought the length of barnacle-encrusted thing aboard. Then we collected the other two moorings, and then we deployed three, near replicas of the ones we are bringing home. Everything worked, as far as we can tell, looking at the slimed machines. As for the data? We won’t know until it has been downloaded and looked at and listened to. I’ll try not to bug Kate about the whale recordings for a few days, at least.
When CEO II popped up, I saw it do so, a cluster of red balloons tied round a box kite, trying to launch itself into the air before settling back to the surface. The buoyant frame contains a zooplankton fish-profiler, a locator beacon, and multiple other instruments to measure pressure, salinity, temperature, dissolved carbon dioxide, and pH, among other properties and less obvious acronyms.
The mooring that replaces CEO II is very similar on top, but at 7 meters off the bottom, we’ve added a sediment trap. The sampling unit collects falling sediment, because most everything wants to fall to the muddy submarine bottom. The trap collects the ocean’s loss in a couple dozen plastic bottles, each rotating into place every couple of weeks. Someone else will venture out next summer to collect it, should things go well.
So far, because things happen and I know things happen, the only hardware I’ve lost on the job was my very first camera, and when I lost it, it had already been supplanted by a newer, shinier, and more reliable model. I was a photographer for the college yearbook. I had also recently joined the college spelunkers, and I wanted to take club photographs in wild Subterranea. I knew whatever camera I took with me had a very good chance of coming out of West Virginia as little more than a grit-clogged box holding undeveloped film. So it was, but in the words of my grandmother, the pictures are and will be grand.
To follow the R/V Sikuliaq, find @Sikuliaq on Twitter and @R/V Sikuliaq on Instagram and Facebook. To chart the course of this August 2018 expedition, look up Arctic Winds, Fish, Fins, and Feathers on Facebook.
—Thanks to the R/V Sikuliaq, Woods Hole Oceanographic Institute, and the University of Alaska Fairbanks College of Fisheries and Ocean Sciences, and the National Science Foundation.