A Quick Turnaround

Last week R/V Sally Ride returned to San Diego after months away. But that doesn’t mean that the ship or her crew got much of a break. Within 72 hours, they were underway again. The summer CalCOFI research cruise will spend 17 days at sea, occupying 75 science stations to collect data as part of its historic data set. 

The marine mammal acoustic team readies their array, while restechs
and technicians from Uwe Send’s lab bring a mooring buoy aboard.

First up, there was lots of gear to unload from the shipyard period. The ship’s crane alternated moving this off onto the dock, and bringing on gear from the many groups that participate in a CalCOFI cruise. It is a full ship, with the labs and staterooms full of scientists. The back deck is more crowded than usual, home to mooring instruments from Uwe Send’s group that will be deployed once all the usual station work is complete. This is a project of opportunity that is part of a NOAA-funded array making observations in the CalCOFI region

The crew also had a few projects to complete, so everybody pitched in to get the ship ready. 

You may remember that Sally Ride hosted the fall CalCOFI cruise last November. To learn more about the science taking place onboard in the next few weeks, check out these posts from that time.

Science Focus: Hydrography

Science Focus: Fisheries

Science Focus: Marine Mammal Observations

Science Focus: Long Term Ecological Research

Science Focus: Plankton sensor

Project of Opportunity: Quantifying Carbon Export

 


Mooring Work in the Gulf of Alaska

R/V Sally Ride is back out at sea after months of upgrades in the shipyard. This first research cruise has scientists from Woods Hole Oceanographic Institute and Oregon State University working on site at an array of moorings in the Gulf of Alaska to recover and deploy anchored strings of oceanographic instrumentation.

Illustration of all the equipment monitoring station Papa.
From OOI’s website.

Station Papa has been a community study site for nearly 70 years and currently supports multiple mooring strings, including a NOAA surface buoy. The OOI (Ocean Observatories Initiative) has been deploying three moorings there since 2013. Once a year, a research vessel full of OOI scientists and technicians makes the trip in order to change out equipment. This year’s trip aboard R/V Sally Ride will recover and deploy replacements of all three OOI mooring strings. All three deployments have taken place and recoveries have just been completed successfully. Each deployment takes up a whole day of work, as they are over 4,000 meters (two and a half miles!) long. They sit on the bottom of the ocean, weighed down by a 6,000 pound anchor, and reach to either 30 or 150 meters below the surface. Check out an earlier post about moorings, back when the ship was in science verification mode, for more details about how scientists use the ship’s equipment to deploy and recover instruments. 

Technicians prepare to deploy a WFP, which travels part of the mooring wire
to sample at different depths. Photo by UNOLS technician Tina Thomas.

There are multiple sensors on each string, including for temperature, salinity, oxygen, fluorescence, turbidity, and density. CTD casts are taken with each deployment in order to calibrate the new sensors using those connected to the rosette frame. Water from the bottles is analyzed in the lab onboard as well. One of the moorings has two WFPs (Wire-Following Profilers, the yellow instrument in the photo on the right), each of which travels up and down a certain part of the wire, sampling throughout its assigned portion of the water column. Each mooring also has sonars to measure backscatter. The large orange spheres in the photo below contain acoustic sensors. A sound wave is produced, and the reflection recorded, from which plankton and other biological populations can be determined. These are similar to the fish finder sensor that Sally Ride has mounted to her hull. 

R/V Sally Ride‘s fantail is part storage (anchors at far left) and part working deck (the anchor to be used for this deployment is in place at the edge under the A-frame) during mooring deployments. The orange spheres house sonar equipment, and the yellow ones are floats that keep the mooring string straight in the water column and bring the instruments to the surface when it’s time for recovery. Photo by UNOLS technician Tina Thomas.

With scientific work completed, R/V Sally Ride has started transiting to Newport, Oregon for offloading. It will then head south to its home port of San Diego. A busy schedule of cruises kicks off with the summer CalCOFI trip. More on that soon!


Photos from the Collaboration with Sproul and FLIP

The collaboration between research vessels Sally Ride and Sproul and research platform FLIP, all members of the Scripps fleet, wraps up in the next week. The three vehicles will return to port having run ~ 25 Remus missions, deployed and recovered wave buoys ~10 times, and completed many more operations with unmanned underwater vehicles (UUVs). Wave gliders and the moored wave buoy have been in the water throughout the trip. Sally Ride‘s small boat has been used for Remus operations, to conduct personnel transfers to FLIP, also bringing food and offloading trash, and to service the moored wave buoy.  

The Terrill group, led by Chief Scientist Sophia Merrifield, is maintaining three weather radar systems between FLIP and Sally Ride. Real-time radar data guides each day’s plans, with the UUVs programmed to sample relative to the wind and wave direction. The UUVs can move at speeds up to 4 knots and run coordinated missions sampling the water column to 100m. Data from the various instruments help scientists understand how the upper ocean evolves as conditions at the air-sea interface change. For more details, check out the previous post about this research cruise. For more on the Sproul‘s contribution, check out this post.

 


Working with R/V Sproul

R/V Sally Ride is out at sea studying surface waves and currents as part of a collaboration between scientists at Scripps Institution of Oceanography and the University of Washington (UW).

R/V Sproul as photographed from R/P FLIP during their collaborative operations
with R/V Sally Ride (not pictured). Photo by Randy Christian.

Other members of the Scripps fleet are in on the action as well, with R/V Sproul and R/P FLIP operating in the same area. Dr. Jim Thomson of UW, one of the investigators on this project, sums up the coordinated effort, “We want to know how winds and waves create turbulence in the ocean. We are looking for patterns in the turbulence, and that requires lots of instruments distributed spatially.”

R/V Robert Gordon Sproul is the smallest vessel in the fleet, at 125 feet long with a crew of five (compared to Sally Ride’s 238 feet and crew of 20), and generally keeps to the waters off Southern California. The ship’s first task was to assist with mooring the research platform FLIP in place (more on this in another post). Then science operations got underway, with autonomous floats built or modified by engineers at the Applied Physics Laboratory at UW being deployed from the ship.

Dr. Eric D’Asaro is chief scientist onboard, and the focus of study is on turbulence, the movement of the water itself. At the air-sea interface in the the upper 50 meters of the ocean, factors include the affects of temperature, wind, waves, currents, and mixing. While the FLIP and the instruments deployed from it remain in one place, the Sproul is deploying drifters, instruments without propulsion, that move with the water.

Scientists use a pole with a hook to snag
the float when it’s ready to be recovered.
Photo by Jeremiah Brower.

Dr. Tom Sanford describes the difference this way – “Consider a person measuring wind and temperature from a hot-air balloon. This is very different from what an observer sees on a fixed tower. For example, the former (hot air balloon) is more likely to observe turbulence without the confounding forces of the wind.”  

All of the floats on Sproul have a metal housing that holds batteries and electronics, with the usual temperature and salinity sensors mounted to it. Some of the floats sink into the water column to study processes over varying depths, and then resurface. Of these, one group has an instrument that measures the electric field due to the water’s motion through the Earth’s magnetic field and from this measures the water velocity. Another is able to be controlled on a fine scale, so its position in the water column can be dictated in order to profile currents using a mounted sonar. Other floats do not sink, and focus on measurements of wind and surface waves, along with the temperature of both the air and the sea.

Jeremiah, the restech in charge of all deck operations onboard Sproul, notes that the ship “is an ideal platform to launch drifters from because its back deck is lower to the water, allowing scientists and techs to simply hand

The floats (in high visibility yellow) are stored on the back deck of the Sproul.
Photo by restech Jeremiah Brower.

deploy many of the instruments.” Being a smaller ship, the higher seas associated with being outside the Channel Islands more often affects work onboard Sproul than it does for Sally Ride. A few times since they’ve been out, the outside decks have had to be secured, meaning everyone has to stay inside and no science operations can take place. The ship has even moved away from the working area in order to shelter behind Catalina Island, returning as soon as conditions allow. Each of the members of the Scripps fleet has its own capabilities, and this collaboration highlights how they are different but can all work in partnership to contribute to scientific goals. 


AUVs Studying Waves and Currents

Sunset recovery of a wave glider. The float portion is up near
the top of the crane arm, while the sub portion is at the rail.
Photo by Dr. Sophia Merrifield.

As you may recall, Dr. Eric Terrill’s group was onboard in December to test drones and a remote-controlled kayak for scientific purposes. They’re back aboard R/V Sally Ride, this time with a different set of autonomous vehicles. They have multiple instruments for measuring the air-sea interaction that occurs at the surface of the ocean and upper water column from the surface to 100 meters depth. 

Wave gliders have been deployed from the ship’s A-frame. For recoveries, the small crane, usually on the forward 01 deck of the ship to load food and other stores, has been moved to the back deck’s starboard rail. There’s two parts to these vehicles, one that floats at the surface and another submerged, connected by either a 4 or 8 meter tether. The sub has fins to harness wave motion into forward motion, moving the vehicle along at 1-3 knots depending on conditions – see the video below.  Sensors record data on the surface and subsurface portions of the platform. The floating platform includes wind, weather, and wave sensors, an ADCP for studying currents, and communications equipment to report its location back to the ship. Solar panels connected to battery packs means the wave glider can operate autonomously for weeks to months at a time. The two wave gliders are deployed from the Sally Ride and brought back onboard every 5-7 days to change sensors and download data.

Postdoc Megan unpacks a REMUS AUV onboard R/V Sally Ride.

The Terrill group also deployed three REMUS AUVs (Remote Environmental Monitoring UnitS Autonomous Underwater Vehicle), for studying subsurface features in the upper ocean. The REMUS is a propelled vehicle, allowing it to operate at speeds up to 5 knots, and down to 100 m depth.  Sensors integrated into the vehicles measure temperature, salinity, depth, chlorophyll, turbulence, currents, and acoustic backscatter.

A moored wave buoy was deployed within the study area to measure waves in one location. In addition, five drifting wave buoys have also been deployed that send real-time information about wave height via satellite.

Scientists and engineers from the Terrill lab track the AUVs and monitor
the WaMos radar from the main lab control center.

The Terrill group maintains a radar system mounted on the ship’s mast, called WaMoS (WAve Monitoring System), that collects information on wave height and surface currents. The data from this will be combined with that from the autonomous instruments. R/V Sally Ride is operating in the same area as the research vessel Sproul and research platform FLIP. Scientists onboard all three are collaborating to understand surface waves and currents using different approaches and technologies, which requires making measurements in rough seas. This marks the first time Sally Ride has teamed up with other members of the Scripps research fleet, and it definitely won’t be the last.


Report from the FLIP

**Guest blogger Randy Christian is a crew member on R/V Sally Ride, but this month is working on FLIP, Scripps’ FLoating Instrument Platform. FLIP is deployed on a project offshore of Southern California, accompanied by other members of the SIO fleet, R/V Sproul and R/V Sally Ride. You can learn more about Randy in this blog post introducing him as second mate, though he sometimes sails as third mate. Learn more about FLIP’s history and specs, including video of it flipping, here. **

Flip, as photographed from one of the boom arms, will be home for the next
few weeks. Photo by Randy Christian.

Research Platform Flip is one of a kind. She was designed and built as a four-year Navy project on a budget of roughly $500,000, according to the vessel’s Captain/Chief Engineer of 30 years (and my boss of the past four days), Tom Golfinos. This was during the Cold War, with the advent of nuclear submarines, and the U.S. Navy was suddenly very interested in learning more about the ocean. The vessel was designed to be towed in the horizontal position, and, when on location in deep water, to have ballast tanks in the cylindrical aft portion of the vessel flooded with a series of valves much like a submarine. Flip is a ship that goes vertical. This vertical position then gives the platform numerous advantages over your average oceanographic research ship. With a 300 ft draft, she is incredibly stable, and with no engines turning propellers (only a single generator for power), she is exceedingly quiet. All of this adds up to a platform perfectly suited to studying numerous aspects of the ocean, from subsurface currents to sound wave propagation; important stuff to know about if you’re navigating the depths and trying to find Soviet submarines before they find you. Needless to say, that four-year project “got extended one year, and then fifty more,” as Tom says in his thick Greek accent. Flip turns 55 this June, and much of what we know about the physical properties of the ocean can be traced back to her. Now operated by UCSD’s Scripps Institution of Oceanography (SIO), R/P Flip is still owned by the U.S. Navy’s Office of Naval Research (ONR).

I am on loan to the Flip from my usual gig as Third Mate aboard the brand new R/V Sally Ride (also owned by ONR and operated by SIO), and this is an exciting opportunity. There aren’t many professional mariners who have flipped a ship 90° and lived to tell the tale, much less who’ve done so on purpose and considered it a resume builder. In the horizontal position, Flip’s layout is odd. Rooms are narrow and tall, there are sideways doors, hatches, catwalks, and ladders, like an Escher drawing come to life. There is even a sideways shower and sink, occupying the same room as a right-side-up (for now) sink and toilet. Reefers and freezers, the entire galley, deck lockers, and all of the bunks are all on gimbals, so they can rotate freely when it comes time to flip the Flip.

Chief Scientist Laurent (left) and researcher Nick prep an ADCP for deployment.
R/V Sally Ride operates in the background. Photo by Randy Christian.

According to the Chief Scientist for this trip, Laurent Grare, a wiry Frenchman with a near-constant smile who is one of the hardest workers I’ve ever seen, Flip is ideally suited to study the interface between the air and the ocean. As wind blows over the water, it stirs up cylindrical currents with an axis parallel to the direction of the wind. Laurent and his team will be deploying and testing acoustic profilers, infrared cameras, and various other sensors with the goal of better understanding how this process works.

With five crew (myself included) and nine scientists aboard, we depart Scripps’ Nimitz Marine Facility in Point Loma at 13:00 on the 15th of March, and are towed out of San Diego Bay by the tug J.M. Hidalgo. I have the 20:00-24:00 watch, which, since we’re under tow, is much easier than what I’m used to. We are towed through the night around the northern end of San Clemente Island to a point about equidistant from San Clemente, San Nicholas, and Santa Barbara Islands, and at around 05:00 on the morning of the 16th, the fun begins. After disconnecting from the tug, we get to work on final preparations. These include tying our personal gear down to our racks, checking that all gear is stowed securely in the lower aft corner of every space so that nothing will drift when turned 90°, ensuring all pins are pulled and all gimbals are rotating freely.

Everyone has an assigned station for the flip, and mine is on the bow with experienced crewmember, Johnny Rodrigues. All hands don life jackets as Johnny and I work our way forward to the bow, closing heavy grating doors behind us, which will become decks. After Tom starts opening valves, the flipping process takes about 25 minutes total. There is not much noticeable change in the first 10-15 minutes, but then the decks start getting a bit slanty, and as the process proceeds it occurs to me that I hope this is the only situation in which I will ever have this feeling. Once we get to about 30°, things start to accelerate and get exciting in a hurry. The sound of water rushing up the sinking hull is audible from the bow, and I hear Tom shouting, “Get ready! Get ready!”

Sproul standing by as FLIP begins to flip. Photo from a previous trip by restech Josh Manger.

Everyone is bracing himself or herself in some sort of position, ready to either step from deck to bulkhead, or lying against the bulkheads, which will shortly transform into decks. I am holding onto the capstan, facing aft and spotting my landing on the bulkhead in front of me. Suddenly there is a rush of acceleration as Flip slings itself upright, and I step gingerly onto my landing spot. For a moment it almost feels as though she’s going to keep going right over, but instead she starts spinning, like someone put the rudder hard over. After a couple of rotations, she settles out, and the flipping process is done. Flip is now a tree house floating in the middle of the ocean. 

Senior hand Dave Brenha and “The Old Man,” Captain Tom Golfinos.
Photo by Randy Christian.

Now the work begins, and there is much to do. Setting three anchors with 640 ft. of chain, 60 ft. of cable, and over 6,000 ft. of thick synthetic hawser each with the help of the tug J.M. Hidalgo and the R/V Robert Gordon Sproul (another SIO vessel) will take several hours, and once that is completed, Flip will not move for 26 days. All spaces are checked to make sure everything gimbaled rotated as intended. Finding my way around is a bit tricky and disorienting at first, as the entire deck plan has transformed. Every room on Flip suddenly has much more deck space in the vertical position, and as the scientists begin to break out their gear, set up tables, and run wires, it becomes clear that one of the most stunning transformations will be the lab.

Meanwhile, out on deck, The Old Man, Johnny Rod, Dave Brenha, and I are climbing, rigging, heaving, and hauling. There are three 60-foot-long booms to deploy, a 40- foot radar tower to erect, and several heavy winches and air-tuggers to move and bolt into position, and Flip’s only motorized lifting device is the capstan on the bow I used to steady myself during the flip. This means a great deal of rigging, using pad-eyes, shackles, lifting straps, and snatch-blocks to create fair leads through which lines can be run up to the capstan. This setup will take us the next three days, and they are long, physical days of intense labor. We all clock over 25 hours of overtime each in these first three days, but it is gratifying work, and we can see the results. Matrik, the cook, has ravenous mouths to feed.

As we get the booms deployed, the scientists are affixing their array of sensors to them and running wires back to the lab, which before long looks like a high-tech command center, with 15 flat screens all streaming data, or about to. We assist with the deployment of a few instruments that will remain submerged, collecting data for our entire time out here.

Lab space aboard FLIP, set up after the platform is vertical. Note the ladder on the wall/ceiling.
Photo by Randy Christian.

By the time Sunday rolls around, things start to mellow out, and I am grateful be able to get some rest. “Now it’s just doing time,” Dave says casually and with a wry grin. While this may be old hat for him and Johnny, for me it’s new and different from anything I’ve ever done before, and has more the feeling of summer camp than prison. There are bright, intelligent people to talk to about fascinating things, there is science to facilitate, and there is meat on the grill. Morale is high, and, barring any unforeseen disasters, I get the sense it will stay that way. The close quarters and the nature of the work leave no room for complainers, victims, or layabouts. Everyone aboard is friendly and positive, enthusiastic about their work and the ocean, multi-skilled, hard working, and problem solving by nature. I have heard the phrase “teamwork makes the dream work” uttered more than once since we flipped and got to work. As corny as the phrase is, it is appropriate. We are all working together for the acquisition of data that will be used in the project of science, the careful and systematic study of our ocean and our planet, and the broadening of our understanding of how it all works. It is a worthy dream indeed.


Trace Metals

Scientists set up to bring metal-free water onboard.

R/V Sally Ride has its first bubble! It consists of a fort of plastic sheeting with filtered air fed in through a flow hood to create positive pressure (see header photo). Dr. Kathy Barbeau and her graduate students set it up in the wet lab in order to keep their work area clean of contamination. Their experiments focus on such low levels of metals, in this case iron, that ambient levels and particles around the ship could interfere. In order to collect the seawater they needed, they rigged up an all-plastic system that was lowered into the ocean on the starboard side of the ship. Held a few meters away from the hull and a few meters below the surface, they pumped water into a carboy. The seawater that comes into the lab flows through metals pipes, which again would add contamination.

Inside the bubble, grad student Kiefer filters seawater to collect the
pellets to be studied.

They are studying the iron levels in fecal pellets of copepods and euphausiids (krill) in order to understand the cycle of trace metals in the ocean. This is part of a collaboration with Dr. Mark Ohman’s lab at Scripps. Both lab teams are onboard R/V Sally Ride collecting and processing samples. Bongo nets are towed over the starboard side of the ship, and the catch is rinsed down into cod ends, baskets at the end which can be brought right into the lab. In this case, copepods and euphausiids are separated out from other critters and kept in seawater rich in phytoplankton (their food source) in a walk-in cold room in the lab. 

On a longer cruise, trace metal work would likely be done in a lab van stored on the ship’s back deck. A container van can be converted into a clean lab, allowing for a contamination-free environment for scientists to work. R/V Sally Ride is designed to accommodate countless setups in order to meet the scientists needs. 

 

 


Zooglider Science

The zooglider is deployed and recovered using a small boat launched
from the Scripps pier. It’s 6 feet long with a 4 foot wing span.
Zooglider photos thanks to grad student Ben Whitmore.

Leg 3 of this R/V Sally Ride cruise is underway after switching out the science party in Oceanside. Samples are being collected by a few different groups, including Scripps professor Mark Ohman and undergraduate and graduate students from his lab. We are operating in the vicinity of a zooglider that was launched recently from a small boat. The glider is an unmanned vehicle that carries oceanographic sensors onboard and can sink to a depth of 400 meters on command. When it surfaces, it sends location information to the lab via satellite. It can stay out to sea for a number of weeks and is then recovered and the data downloaded from its sensors.

Scientists are collecting biological samples using the MOCNESS (multiple opening/closing net environmental sampling system), which is deployed from the back deck of R/V Sally Ride. They have done tows to 400m around noon and midnight each day, to account for the fact that critters move shallower in the water column after dark. The samples will be compared to pictures taken from a camera system on the zooglider, in order to determine whether krill and other animals may be avoiding the glider. The camera takes a picture every 0.5 seconds, capturing images such as those below. The abundance of various species can then be inferred based on how many were spotted by the camera. But it may be that those calculations aren’t indicative of the actual population, if the animals move away from the zooglider as it approaches. The net tows, however, are harder for them to avoid. 

Images from the camera on a zooglider. On the left is a jelly, and on the right is a copepod, the main subject of study in Dr. Mark Ohman’s lab. 

The MOCNESS tows take a few hours each. You can read more about how the net system works in a previous post. Sensors are mounted to the net frame, including a CTD (conductivity, temperature, depth), oxygen, fluorometer, and transmissometer. Live readings from these sensors are monitored by scientists in the lab during the cast, who give directions via radio to a crew member running the winch. When the package is brought back onboard, the ten nets are washed down with seawater. This rinses all of the critters caught along the length of the net into the cod end, which is then removed and brought into the lab. More rinsing and filtering is done, and then each sample is preserved for further study. Check out this 360 degree view of a MOCNESS recovery on the ship’s fantail.

The nets provide data about animals found in each depth range; each collects a sample covering 20-100 vertical meters at a time. With the camera, that resolution will be narrowed down to 5 centimeters, giving much more useful information about whether specimens are interacting with each other. This is the first study to take place when the zooglider and net tows are operating at the same time and in the same area as each other. Testing that the camera system can be reliably used to make inferences about zooplankton populations is part of making it a valuable tool. 

On deck, each of the ten nets are rinsed (left), flushing the sample into the cod end.
In the wet lab, students filter and preserve the samples for study back on land (right).

Ground-Truthing

Onboard R/V Sally Ride, and in oceanography in general, a lot of sensors are used to collect information. In order to check that inferences made are backed up with data, ground-truthing is required.

Grad students deploy a hydrophone to listen for marine mammals,
while others scan the horizon for spouts and splashes.

On leg 1 of the current cruise, scientists used passive and active acoustic sensors to determine the density of animal populations. There are sensors attached to the bottom of the ship, as well as on lines that are anchored to the seafloor, with instruments throughout the water column. These moorings collect data for months at a time, and are more likely to observe “normal” animal behavior, as schools of fish and other animals may act differently when the ship is near them.

Observing actual specimens is needed to be sure that the conclusions made using sensor data are correct. Net tows are performed, including a MOCNESS that samples throughout the mid-water column and a manta net at the surface. Visual surveys were conducted during daylight hours, with a student outside watching for whale spouts and dolphin splashes. Meanwhile, another student was in the lab listening live to a hydrophone array being towed behind the ship. Matching up the sounds and visuals in this manner will help the team identify recordings from the hydrophones that are attached to the moorings. 

The surface buoys and moorings that were recovered and deployed on leg 2 housed dozens of instruments, which are calibrated before and after spending months in the ocean. Other sensors, either mounted on the ship itself or

A cage of instruments that will be attached below the buoy is first
sent down attached to the CTD frame in order to calibrate the sensors.

connected to the CTD rosette frame, are used. Knowing any offset between sensors is a start, but water samples from various depths were also collected on CTD casts. These will be analyzed back on land for salinity, dissolved oxygen, and nutrients in order to double-check the sensor data. 

Sensors mounted to and deployed from R/V Sally Ride are an invaluable tool for scientists, collecting data for long periods of time with little supervision. But the extra step of ensuring their accuracy is necessary. On this cruise, scientists who rely on sensor data spent hours confirming their data is the best it can be. The ship has the latest and greatest sensors and instrumentation, and the crew is practiced in safe and efficient deployments and recoveries, so it was a productive trip. 


Buoys in the California Current

Dr. Uwe Send’s lab group at Scripps Institution of Oceanography consists of grad students, scientists, technicians, and engineers that fabricate, maintain, deploy, and recover instruments all over the world. This week they’re on R/V Sally Ride recovering a mooring, and deploying a new one in its place. This one is attached to a surface buoy, unlike the other mooring operations done on the ship so far which have been completely underwater. Click here to see a 360 degree photo of the buoy recovery.

The buoy was hooked from the starboard side and then recovered over the A-frame. Hours later, instruments along the 770 meter long line were still being brought onboard.

During recovery, the instruments near the surface came up with a lot of marine life attached to them, called bio-fouling. They are coated with a paint designed to discourage growth, but it doesn’t stop it entirely. Over the course of a few hours, the entire string of instruments was brought onboard. Data was downloaded from the various sensors, and the replacements were fully tested before deployment. A CTD cast was done in the vicinity just before or after each operation. The data collected from sensors attached to the rosette frame will be used to calibrate the data coming in from similar sensors on the buoy and mooring.

An instrument cage before deployment (left), and after it’s been underwater for a year.

The mooring is at a strategic site in the zone studied as the California Current Ecosystem by the Long Term Ecological Research project. Dozens of sensors are attached, from the top of the buoy to near the seafloor 770 meters below. Some transmit data back to computers in the lab while others have to wait for recovery to have their data downloaded. There’s wind, rain, temperature, humidity, and light sensors on the buoy itself, along with a GPS beacon, AIS (automatic identification system, which shows up on ship radar), and a flashing light. Below the surface are sensors for dissolved oxygen, pH, salinity, temperature, nitrate, carbon dioxide, light, and water current, along with hydrophones and active acoustic devices that collect information on the density of animal life. 

Sensors are secured in the top ring of the buoy, as well as
through the cage and down into the water column.
The anchor is also visible in the bottom right.

The deployment takes place top to bottom, with the buoy first in the water. It is towed behind as the ship moves slowly (0.5-1.5 knots) and the other instruments are attached to the line. Last to be deployed is the anchor, in this case a stack of train wheels weighing 1700kg (~3700lb). 

These moorings are a joint effort between multiple groups at Scripps and NOAA (National Oceanic and Atmospheric Association), an entity vital to studying the health of the planet. Each group contributes some of the instrumentation, manpower, ship time, and data processing in order to make the effort successful. The goal is to have long-term uninterrupted data about the condition of the ocean, from seafloor to just above the surface. All operations on this trip were a success, thanks to the crew and science party onboard R/V Sally Ride.

This project is made possible with funding from the NOAA Ocean
Acidification Program and the NOAA Climate Observation Division (COD),
as well as funding from the National Science Foundation (NSF) trough the
CCE-LTER program. Additional contributions are coming from U.Send’s lab,
the PMEL Carbon group, the NOAA Southwest Fisheries Science Center and
from all collaborators. The initial year of the mooring program was
supported also by the NOAA National Marine Fisheries Service (NMFS), the
UCSD Academic Senate and UC Ship Funds. Any findings expressed here are
those of the author(s) and do not necessarily reflect the views of the
funding entities.