Month: November 2024

Howdy all,

What an awesome journey we’ve had over these past two months of leg three! We’ve hit some major milestones over the last two weeks – completing all our long station sampling, wrapping up our uCTD casts, finishing the underway system collections, and getting the ship clean and packed up. Our next stop is Papeete, Tahiti, where we’ll resupply and exchange our crew and team of scientists!

Long Station 12 went off without a hitch with more successful deployents and recoveries of our CTDs and arrays. But Station 13 (appropriately named) threw us some curveballs. Our intended location for Station 13 was at 30° S location, but severe weather forced us to pivot to 27.5° S. Even there, we faced some of the roughest seas of our entire cruise. With high winds and large swells, deployments were more challenging and stressful for our equipment. Particularly pushing our CTD/rosette’s .322 electro-mechanical wire close to its safety limits.

Despite the challenges, Station 13 proved to be a triumphant finale to our main research operations. We successfully:

• Deployed all ARGO and NKE floats
• Secured all arrays
• Collected, processed, and stored valuable hydrographic and biogeochemical data sets
• Completed our 161st (and final!) celebratory uCTD cast

One of the most rewarding aspects of the SPOC cruise has been getting hands-on with our the various types of equipment. There was something special about not just operating but truly understanding and maintaining instruments like the LISST, UVP, uCTD, HyperPro, wirewalker, and various GPS beacons to name just a few. Developing this understanding has improved my confidence when working with this equipment and my technical abilities as a whole. 

We’re now transitioning into the final phase of my third leg- KM2419, an ocean floor mapping cruise from Tahiti back to Hawaii. The labs are cleaned and packed, ready for the transit home and subsequent HOT cruise. Stay tuned for updates for my experiences in Tahiti and the start of the mapping cruise!

All the best,

Hunter

 

– Sunset from Station 12

– The birthday cake that the galley crew was kind enough to put together for me

– One of the last uCTD recoveries near 30 degrees South complete with high winds and large waves

– Briana and I post uCTD #161 recovery

– The Wirewalker stripped down for cleaning before we packed it up

– A team of awesome people celebrating the conclusion of the SPOC cruise!

 

 

End of Cruise: CTD Wrapped (11/17 – 11/24)

A significant portion of the work fellow MATE Intern Hunter and I did consisted of taking Conductivity, Temperature and Depth Profiles (CTD) work in two main forms; underway CTDs and CTD Rosette Cast. Over the course of this 34 day cruise, Hunter and I completed over 161 underway CTD and over 101 CTD Rosette cast, generating a nearly complete data set of a transect from 21N^o to 27 S^o. 

Our 161 underway CTD cast also appears to break a couple of records by a long shot. The second, third and fourth data sets contain an already impressive 83, 48 and 45 uCTD’s, but we doubled it!

Our mentor, Tully Rohrer praised us in casting over 161 underway CTD and experiencing very minimal problems besides some mechanical issues that came with wear and tear of the instrument. Tully once painful recalled how there was a cruise where the team kept getting tangled or as Tully calls them “Wuzzles” and how long and hard it was to untangle the line for hours. Thankfully we didn’t run into any issues with that, phew!

– Tully Rohrer rinsing the underway CTD to start packing it up at the end of the cruise

I really enjoyed casting the uCTD’s because it gave us an excuse to go out and stare at the ocean every 2 hours for about 25 minutes. I was being silly one night and calculated that over the 161 cast that we completed that we both stared at the ocean for a cumulative of over 60 hours or about 30 hours each! Pretty crazy if you ask me, but super fun!

– Fellow Mate-Intern Hunter Adams and I celebrating our last uCTD

The SPOC team celebrated our last uCTD cast #161 by standing by as Hunter and I tearfully casted our last one. Data wizard Dr. Daniel Murratore promised us to analyze our cast once it was retrieved and they delivered these beautiful graphs! I am so excited to see the paper and the research that will eventually reference this impressive data set, hopefully soon!

– SPOC Team helping us celebrate our last underway CTD thus concluding a 161 run!

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Another major and significant component of our work was the CTD Rosette Cast that took place every 3 hours while at the long stations. 

There were 5 long stations, each containing about 19 – 21 CTD casts, culminating in a total of 101 CTD casts! Most cast traveled to 250 meters ~ (820 ft) since the team was mostly interested in surface processes but we did have at least two 1000 meters cast for each long stratton (for diel studies) and a handful of cast that went down to ~3500 meters for calibration purposes.

Running the CTD console was an exciting experience that taught me a bit about double checking your work, keeping cool under pressure, reading water column profiles on the fly and communicating via radio. Running the CTD was a multi step process that typically involved empty niskins, and then caulking them i.e attaching lanyards to the hooks on the CTD Rosette. Once those are attached, you turn to the bottom of the niskin where you attach the lanyard hooks to the bottom of the bottle, opening them in the process. Once the niskins are set up, you take multiple laps around the CTD, making sure that the bottle caps at the top of the nisking which control the pressure at which water leaves the spigot are closed tightly enough. Then you take another lap making sure that all the spigots at the bottom of the nisking are sticking out, so as not to lose samples when you’re moving the CTD back onto the ship. Failure to do all the steps above could result in damage to the rosette or the niskins which should be avoided at all cost. 

– Briana Prado caulking CTD bottles 

The last lap you take is to take off the caps off the sensors. This CTD rosette was equipped with a UVP, PAR, LIST and syringes on the oxygen sensors, so I’d have to make sure that those were off and ready to collect data. Once the CTD Rosette is set up, I turn back to the lab, collect my cast sheet and relay the information on the cast sheet to the log sheet where I’d take note of starting and ending latitude and longitude, depth of the water column, time the CTD Rosette went in and out of the water, and the depths at which we are firing the bottles. While that is happening, the Ocean Technology Group (OTG) is communicating with the Hawboldt Winch operators about picking up the slack in the wire to get the CTD ready for deployment. Once the slack has tightened, I get ready to turn on the Seabird Deck Box and to start recording on the Seasave software, a software that relays all the live information from the CTD Sensors and rosette back to the ship and the computer you’re working from.  Once all that is set up and running, you communicate with the back deck and tell them the package is ready for deployment. The OTG group then checks in with the bridge to get their approval, once warranted, the OTG group checks in with the winch operators to then deploy the package. 

Intern: “Back Deck – Lab, the package is ready for deployment.”

OTG:  “Roger that lab, Bridge-Back Deck “Can we deploy this package?”

Bridge: “Back Deck- Bridge, You are clear to deploy the package.”

OTG: “Roger that, Winch-Back Deck, Are we clear to deploy the package?

Winch Operators: “Back Deck-Winch, Roger, We are now deploying the package”

Once in the water, we let the CTD soak at the surface, to allow the sensors to equilibrate with the water temperature and start pumping water through the sensors. After about a minute, I radioed the Back Deck to take the CTD to a pressure-depth of 15 deci-bars at 30 meters per minute. It is essential that the package travel at this specific speed as that is how the CTD sensors are turned on.. Once the CTD pumps are on, I communicate again with a back deck OTG person that we are now clear to take the package back to the surface and then to Target depth ~ 250 meters. Once that is done, we are now ready to take our water column profile.

The CTD profile generates right in front of your eyes. It’s always fun to take note of the chlorophyll maximum or the part of the water column, where most of the phytoplankton are hanging out and see how that changes, hour to hour, based on the time of the day, where we are in the ocean and other oceanographic parameters like oligotrophic waters. Other things we keep an eye out for is the Cpmax or the area of the water column with the highest concentration of particles. 

Once we reach our desired depth of lets say ~250 m, we are clear to start firing bottles. The winch operator will declare they have reached the desired pressure/depth.

Winch: “Lab-winch we’ve have hit target depth 250 db or 2-5-0 decibars”

Intern: “Winch- lab, next target depth is 125 db or 1-2-5 decibars”
Winch: “Roger that “Next target depth is 125 or 1-2-5 decibars”

We then wait for the winch to call out 125 decibars, which we double confirm by looking at the screen and reading where the CTD tells us it is in the water column. Once we’ve reached the desired depth, I wait 30 seconds to fire the first bottle. This time is allotted to allow for any disturbances in the water column to settle. Once I fire the first bottle any subsequent bottles are fired at 10 second intervals, for the same reason. 

Once I’ve fired the bottles I call out to the winch our next target depth and repeat.

Once we’re near the surface, I call out to the back deck and tell them that we are now clear to recover the package and OTG begins checking in with the winch and bridge folk to confirm they are also ready to recover. 

Once the package is recovered, I finish jotting down the meteorological data, log the event in the event page and turn off the deck box. It is paramount to turn off the deck box because you don’t want to electrocute anybody when they start releasing the slack on the wire. 

For our last cast, cast #101, we went down to a depth of 3500 meters (~11,480 ft). This cast was used to calibrate the CTD’s oxygen sensors and also collected water from the Antarctic Deep Water water mass. As the name implies, this is water that last saw the surface of the ocean, when it downwelled off the coast of Antarctica.  As a result the water is super cold, oxygen rich and salty! Chief Scientist Angelicque White was super cool and boiled down the water to collect and bottle salts for us as a memoir as well as let us cast away a couple pieces of styrofoam to crush them underpressure. We didn’t have too much styrofoam so we had to experiment with different types… some were more succesful than others.

– Before and after pictures of our styrofoam squares that went down to a depth of 3500 meters!

 

Now that we are done with all the stations, we’ve started to pack up labs. We will be arriving to Tahiti soon, stay tuned! 

Cheers,

Briana

Practicing Diligence at Sea: Week #6 (Nov 11th – Nov 17th)

Safety at sea cannot be understated. This week, I had a few close calls while conducting back-deck operations that have made me acutely aware of the importance of preventing issues before they have the opportunity to escalate.

While deploying the wirewalker at the fourth station, we had an issue with the quick release. A clamp that is supposed to release when you yank it. This release transfers the load from the main line to the release when it’s time to release the buoy onto the water. It’s essential to release the clamp at the right time because if not the buoy and its packages might get dropped into the water from a height and damage them. Or if you wait too long, it can become harder to release the clamp because there is no longer that tension that would allow it to release. 

Well… when we were deploying the buoy, the rope on the clamp got twisted under the leading line in a way that regardless of how hard I yanked, I could not get the clamp to release. I now found myself progressively getting closer to the edge of the stern and playing an unbalanced game of tug of war with the buoy as the A-frame moved the package away from the ship. Despite the rope burn, I held on because I was scared that if I’d let go, I’d lose the buoy/clamp. 

Tully and Ben stepped in with about a foot of rope left, but then quickly halted operations as it became apparent that the clamp would not release.  By stopping operations we had enough time to think about our next step, which just meant, letting go of the rope, bringing the package back onto the ship, and trying again. No biggie. The alternative situation where I could have gone overboard trying to get the clamp to release could have been much worse. If you ever find yourself in a situation between your safety and that of the instrument, safety comes first. Of course, if we could mitigate any damage to the instrumentation that would be ideal, but not if someone gets hurt. 

A couple hours later while deploying PP arrays, I was handing over the primary production bottles when the whistle on my life jacket got tangled with the samples I was holding. I only noticed this issue when I was about to pull away and couldn’t get too far because the whistle’s rope was now stuck to the line. Had we reached the point where we were about to deploy the sample, it would have taken me with it. So we took a pause to untangle my whistle and proceeded with the operation. The lesson was that it’s okay to call for an “all stop” to address an issue before proceeding and to be very mindful of things that can become snagged. Not doing so could have made this issue much worse.  

Another thing to keep in mind while conducting back deck operations is rope bights and how you handle rope. It’s easy to be focused on collecting your sample from the line when all of sudden you find yourself in a bight that could tighten around your ankle or hands at any time. 

It’s also important to not wrap the rope around your hands for the same reason. Instead, if your wrapping loops, wrap the loops on top of your hand instead of around and hold the center, this lets the rope slide through your hand instead of tightening around it. Last but not least be mindful of rope slacks from the A- frame, it can be easy to get entangled in them if you’re not paying attention to what’s happening to the rope overhead. It’s all in the details and situational awareness. 

And of course, always wear your hard hat, life vest, and steel-toe shoes when conducting back deck operations, you never know what could fall or roll onto you, but it really is just a factor of time until something does. 

Other than some close calls, I’ve been doing good. We have now completed Long Station 3&4 and are now en route to our last long station, station 5. Stay tuned for more updates!

 

Cheers,

Briana

Howdy all and welcome back,

Apologies for the later post, but the good news is there’s a lot to catch up on! We’re two weeks into the SPOC cruise and currently en route to 20° S Latitude. Since the start, we’ve been conducting various operations, including underway CTD (uCTD) deployments, ARGO float deployments, “short station” CTD casts, and “long station” array/CTD deployments. Our ultimate goal is to collect diverse data in the South Pacific, a critically understudied region, as we steam to 30° S. This data will primarily focus on understanding the rates and mechanisms of primary production and respiration in this area.

During transit between our five long stations, we’ve been using the uCTD to survey the surface 400 meters of ocean. This operation involves deploying a probe from the ship’s stern, equipped with sensors measuring dissolved oxygen, fluorescence, conductivity, temperature, and depth. The beauty of the uCTD is that we can continue cruising at 8 knots while collecting data on both the downcast and upcast. We’ve also been utilizing the Kilo Moana’s underway seawater flowthrough system to sample and analyze surface ocean water. Sprinkled in with these activities are Argo float deployments, contributing to an international ocean monitoring initiative that uses autonomous floats to create hydrographic profiles of the upper 2000 meters of the world’s oceans.

When not transiting, we’re on station performing CTD casts and free-floating array deployments. Before crossing the equator, we focused on performing short station CTD casts as weather was too variable and currents too strong to deploy the arrays necessary for a long station. These short stations lasted about an hour, and after we finished collecting our samples/data, we were underway again, so these stations were fast and furious. 

We officially crossed the equator on Halloween, which was a happy surprise! Of course, everyone dressed up in costumes (yours truly was a hero in a half shell), and we had a full equator crossing ceremony for the “polliwogs,” aka sailors who are crossing the equator for the first time. My given wog name was Richard Simmons’ Baby goes to sea. This ceremony involved proving our skill to the Court of Neptune in the form of a talent show (I did a skit with two of my fellow wogs) and if we displeased the court with our skills we were forced to fight the spirit of a sea monster (a pinata). Overall, it was a blast of a Halloween full of karaoke, candy, and dancing.

Shortly after crossing the equator the real work of the cruise began as we started to hit our first long stations. When we arrive at these stations, we deploy multiple arrays and run 24-hour operations for the next two and a half days. We deploy a sediment trap array, a primary production/gas fixation array, and a wirewalker array with each long station. The sediment trap array uses a series of tubes with formalin/brine in the bottom to capture and hold marine snow particles, aka sediments, that sink from the surface ocean. The primary production/gas fixation array uses C-14 enrinched seawater samples (collected on station) to determine the rate of primary production. The wirewalker array uses an ingenious design involving locking cams, positive buoyancy, and wave action to collect multiple sensor profiles from the surface ocean. Our latest wirewalker casts have produced ~120 profiles from each station (which is a lot). Array deployments and recoveries are some of the most exciting operations we’re doing on this cruise, as they involve a lot of coordinated deck work, and recoveries are conducted by grappling the arrays with grappling hooks! In addition to assisting with array deployments and recoveries, one of my responsibilities is managing CTD operations. This involves maintaining the senor suite aboard the rosette, downloading/processing data, and working with OTG techs/ship crew to collect water samples from different depths. Some of the new sensors I’ve been able to work with include a Underwater Vision Profiler (UVP) and a Laser In-Situ Scattering and Transmissometry (LISST) instrument. The UVP photographs small particles within a set volume of water and the LISST uses lazer diffraction to measure the size and quantitiy of suspeneded particles!

So far, we’ve hit long stations at 5°, 10°, and 15°, and besides minor issues with equipment and sample collection, the cruise has been going smoothly. This has been one of the most involved cruises I’ve ever participated in with nonstop ~80 hour work weeks but its been incredibly rewarding and I’ve had the oppourtinity to learn a lot. I’m now appreciating the importance of time management on long cruises like this, as it can be challenging to get enough sleep, eat well, exercise, and still have a strong attention to detail for 12-hour shifts. We have two more stations to hit before we can begin heading to Tahitit and the OTG techs, ships crew, and science team have all been working hard to collect this one of a kind data! By the time we finish up our last long station I’ll have my next blog post up so stay tuned!

Until then,

Hunter

 

– The underwater CTD and its “reel”

– The wirewalker. Inside the yellow covers there is a suite of sensors that measures the physical and optical properties of the water column. 

– The sediment trap holder being added to the array line

– Crossing the equator on Halloween!

– One of many oceanic white tip sharks we’ve seen since stopping at long stations. Photo credit to one of the Kilo Moana’s ABs Stephanie for capturing this image with a GoPro on a string!

– General idea of where the R/V Kilo Moana is currently in the Pacific ocean

We arrived at our first long station on Nov 2nd around 3 pm and arrived at our second long station on Nov 6th. The long stations are the meat and potatoes of the Ocean Carbon biological cruise as that is where scientists will be performing incubations, collecting water from depth, and conducting in situ experiments using arrays. Each long station is a 60-hour sampling storm with Conductivity Temperature and Depth (CTD) profiles taking place every 3 hours, sediment traps, primary productivity arrays, float deployments, and more! 

Immediately upon arriving at each long stratton, we deploy one of Dr. Henderikx’s floats. This float will be released into the water for the rest of its life where it will be conducting CTD profiles of the water column a couple times a day and then relaying that information to a satellite at least twice a month. This information will then be used to calibrate data collected from satellites hovering on Earth to what is happening in the water column. 

– Dr. Daniel Muratore and Tully Rohrer Deploying a Float upon arriving to a long station

The second and third orders of business are to deploy sediment traps and the wirewalker to collect the most data while we are at the station. Unlike the float, these will be retrieved at the end of the long station. To make our delicate samples and wirewalker visible and retrievable, we attach the samples to buoys that are bright yellow and have flashing lights, GPS, and a radio transmitter on them. The buoy is also connected to a string of floats that help counteract the weight of the samples, optodes, and weight at the end of the line. 

The sediment traps contain two sets of traps, one for trace metal analysis that uses brine as its trapping material and the other for overall organic matter exports outside of the photic zone that uses formaldehyde to preserve the samples. These traps are placed at a depth of about 150 meters, right under the photic zone and its goal is to trap as many of the particles that sink out of the surface. Most often it tends to be dying phytoplankton or bits and pieces of things that get stuck together and it represents carbon exiting the photic zone and beginning its slow descent into the bottom of the ocean…

– Deploying Sediment traps into the water. Top are trace metal clean sediment traps filled with brine. The bottom set of sediment traps are filled with formalyn to preserve particulates that have fallen in.

The third order of business is the wirewalker. The wirewalker is like a float in that it takes CTD profiles; however, it is attached to a buoy and it can take over 70 water column profiles a day. It utilizes wave energy and can be described as a pong brick moving up and down the wire up to depths of 400 meters in less than 30 minutes. This is an important instrument as it provides the oceanographic context to which we are sampling over the 60 hours. 

– Wire walker being deployed into the water

Once those are all deployed we can finally deploy the CTD rosette to start collecting water and generating a water column profile and the scientist can start doing their water incubations for upcoming experiments. There is an assortment of things that the science team samples for. Sometimes the team takes water to sample oxygen concentrations and particulate organic carbon. This cast is used to calibrate the oxygen sensor on the CTD. Then there is another cast where the scientist takes water to measure chlorophyll and uses the results of that to calibrate instrumentation.

My favorite cast is the Primary Productivity and Gas Array (PP Array). This cast is for collecting samples that will be used to test the rate of Nitrogen Fixation using N¹⁵, dissolved inorganic carbon consumption using C¹⁴ and oxygen production using O¹⁸.

– Dr. Daniel Muratore and Tully Rohrer spiking their incubations with N¹⁵ in preparation for the insitu PP/Gas Array deployment

During the CTD cast we “fire” bottles at 6 specific depths; 125m, 100m, 75m, 50m 25m, and 5m. These samples will then be placed back into the water at their respective depths, where they will sit in the water column for 24 hours replicating conditions that they were collected in. This cast always takes place at least 3 hours before sunrise, approximately ~1am in our current location. The CTD  samples are typically back on deck 30 minutes later and then put back in the water hopefully no later than 3 am – which is about when the sun is starting to rise in our current part of the world. It’s a bit of a scramble to get everything spiked with N15, C14 and O18 respectively before the samples are supposed to be in the water but it sure is exciting. While deploying this specific array, all lights have to be turned off and only red lights are allowed to prevent the phytoplankton from photosynthesizing too early, which adds to vibe ~

– Primary Productivity and Gas Array being deployed at 3am using red lights

 This ALSO provides the perfect opportunity to get a peak of the milky way and stars. There are definitly more stars in one corner of the sky than there were in the whole sky where I grew up in suburban San Diego. It take my breath away every-time!

This week I also celebrated my birthday! The galley staff were really kind and baked me a cake! It was delicious! 

Cheers,

Briana
 

Equatorial Musings While in Transit to 5°S!

Hey there! Things are well underway! When we are not conducting underway CTDs (uCTDs) or performing our daily grabs using the regular CTD Rosette 3 a.m. grab, we are cruising at a solid 9 to 10.5 knots!

Our cruise plan has changed a bit since the start of the journey due to challenges presented by weather and field conditions. Unfortunately, we were unable to conduct a long station in the northern hemisphere, but new opportunities to sample at 5, 10, 15, 20, and 25 degrees south have emerged. Therefore, the updated plan is to steamhead to 5 degrees south to begin the first long station and get underway with the bulk of our work.

While in transit, we crossed the equator on Halloween, which was highly anticipated! It was soooo anticipated that I even made a CTD Rosette costume while we were still in port, largely because I was inspired by the CTD, and I had heard that the equator crossing would be a pretty big deal,  especially because it was on Halloween!

– The subpeona inviting us to present ourselves before King Neptunes Court

Since the 1600s, crossing the equator (0°00.00) has been seen as a rite of passage, a good opportunity to boost morale and prove your seaworthiness. Despite its many variations, this seafaring tradition has persisted into modern times. The celebration typically involves a series of dares that Pollywogs, those who have never crossed the equator must complete to prove their seaworthiness. The Court of King Neptune and Davy Jones, along with his Committee of Shellbacks (those who have crossed the equator before), then judge your performance and decide whether to welcome you to the Kingdom of Neptune. In the past, they might have asked you to do some gnarly things, like crawl through chutes of rubbish, drink a “truth serum,” and eat uncooked eggs. Luckily, the Court of King Neptune aboard the Kilo Moana are much nicer and asked us humble Pollywogs to either perform a talent or sing karaoke while reading out the “crimes” we’d committed during our time on the ship. The “crimes” are not really crimes but more like hilarious superlatives. I was accused of enjoying the solitude of the night shift, hiding Hi-Chew candy, and being obsessed with the CTD, which they are not wrong… To repent for my “crimes,” I chose to sing karaoke to “Rich Girl” by Hall and Oates. Some of my fellow crewmates performed skits, told stories and jokes, and even did a whole dance routine! It was so cool to see everyone let loose and have a little fun on the back deck as the sun went down!

 

-Fellow Mate Intern, Hunter Adam and I in our Halloween Costumes 

We ended up crossing the equator later that day at around 05:06:56 UTC. My friend and I crouched by one of the consoles for a few minutes, counting down every second until 0°00.0000. The console only delivered 0°00.0001, which was a bit disappointing but still neat nonetheless.

– 

With one day away from our first long station, the Halloween/Equator Crossing was a nice “rest day” or, like its original intention, a good morale booster—a calm before the sampling science storm!

Cheers,

Briana

– Kilo Moana crew dressed for Halloween and Equator Crossing