24°S Rhymography

by A. Sanchez-Franks

 

In a commercial port in Rio, the James Cook had found its berth

For a voyage to capture data where measurements are dearth

The intent was to study the ocean’s impact on the global climate

Thus the team embarked; their lead a renowned scientific pirate

 

The ship’s departure featured widely on local Brazilian news

With coverage of the send off for the hydrographic research cruise

At the reception, diplomats addressed a diverse and cultural nation

And toasted the UK-Brazil Year of Science and Innovation

 

It’s been a week, science is underway and labs have found routine

All nutrients, CFCs, carbon and the oxygen team

Isotopes, echosounder, TSG and bathymetric lines

With intentions to deploy the CTD over one hundred times

 

Endless ocean, rolling swells and the bluest waves all capped white

Yet not a fish, nor bird, nor beloved mega fauna in sight

A barren oligotrophic wasteland where very little can transpire

Such is life – or lack thereof – when crossing the subtropical gyre

 

Meanwhile engineers and deck crew keep the ship on even keel

On the bridge, dynamic positioning can be a pretty sweet deal

Groaning stomachs and tired heads draw all to the galley

Where enormous meals and cheesecake cause flagging spirits to rally

 

A fuse on the deck unit goes as we start the next station

Collective groans signal the CTD needs re-termination

Technicians find the cable has turned out quite refractory

Chief Scientist blinks hard, stating, most unsatisfactory!

 

Still we steam on, monitor progress and secure all the rope

So a smooth deployment can be ensured for the next Argo float

To the Mid-Atlantic ridge and beyond we’ll boldly sail

Though not before the mid-cruise break: BBQ on the fantail

 

Myriad watches and shift changes from dawn to dusk and night to day

Still the rosette keeps swinging back to the starboard staging bay

Water drops drip off its niskin bottles in hi-beam moonlight

Weary samplers fall in line as the ship steams into the night

 

The ocean surface reflects a full moon framed by countless stars

Softly below, the rosette rests near five thousand decibars

Oceanographer’s worlds unite at this air-sea interface

The horizon gives us sense of unexplored infinite space

 

Lab coats, science samples, data points, and many systems under way

Pink-skied sunsets, foc’scle deck workouts, and chocolate on Sunday

Sadness shrouds the ship as the end of this research cruise draws near

On the other hand, [the gloom is brief] since on land we’ll have beer!

 

From Rio east to Walvis Bay and then south, quite a ways down

To the home of Table Mountain, the very beautiful Cape Town

South Africa’s welcome is bittersweet; here we’ve reached the end

Now back on land and to the lab to check the data for a warming trend!

 

 

 

 

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Life Around the Rosette

by Kat Giamalaki

“Hurry! The CTD is at 100m depth!”

Sampling bottles – check. Station log sheet – check. Hard hat – check. High visibility vest – check. Safety boots – check. I’m good to go!

“Bonj (shortcut for bonjour) Thierry! Thanks for helping with carrying the sampling boxes”. After a few steps I’m out on deck. Suddenly, it gets warmer, sunnier and more crowded. People running around, sometimes stressed other times more relaxed, carrying various sampling bottles, getting ready to drain the 24 Niskin bottles that are about to arrive at the sea surface. Each Niskin bottle carries water from multiple depths throughout the water column as the instrument travels towards the surface. The water here is so clear that we can see the CTD even when its on 10 meters depth. It is exciting to see such a massive metal structure coming out of the water in such an elegant way!

When the instrument finally makes it on deck the technicians connect the cables to receive the LADCP (lowered Acoustic Doppler Current Profiler) data and then give way for the magic trip from the deepest to the shallowest waters of the station. The process gets repeats every station and the sampling queue is very specific: first come the gasses before they get contaminated by the atmosphere, then nutrients paired with the radiocarbon, and finally salinity, chlorophyll and micro-plastics that are not affected either by the air or the samplers. The ChloroFluoroCarbon (CFC) team starts and goes as quickly as possible to minimize air-sea water interaction. Then the Oxygen people follow and then us, the Carbon team. Niskin number 1 brings water from the dark deep, here in the South Atlantic that is around 4000-5000 m. Its temperature is below 6°C, which feels very pleasant in the subtropical heat. We develop specific moves that become routine. Put the gloves on. Fix the tube on the Niskin and push the valve on the Niskin spigot for water. Rinse half the bottle twice to remove any previous sample remainders. Make a twirl as you empty it so there won’t be any  trapped air on the sides of the bottle. Fill it up while slowly pinching the tube. Let it overflow for approximately 15 seconds. Remove the tube carefully, close water valve and seal bottle. Shout out the Niskin number you’ve just done… and here we go again. I’m usually teasing Gadaffi from the physics team who keeps us in order (and has a very distinctive laugh!) while I’m waiting for the next Niskin.

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Taking water samples around the rosette (image: K. Giamalaki)

As on each trip, your co-travellers have a big share in the fun. We’ve been extremely lucky with that part. Brilliant scientists of all levels, including professors and PhD students, are making this circuit incredibly special. After a few trips, you get to know the people around the rosette pretty well. You have inside jokes – the splashing water from my sampling bottles have become an enjoyable shower for Frederico from the oxygen team. Vanessa helps Fred by measuring the temperature for the oxygen samples to the sweet tunes of her samba playlist. Thierry is collecting nutrients and is always singing the characteristic soundtrack of ‘Jaws’ when he’s approaching to make me go faster since he comes after me. I’ve lately received a cold shower coming from approximately 2000 meters deep– it was literally freezing. Gen from CFCs is always quick to laugh – I’m saying ‘Hi’ to her every single time we squat to start sampling the next Niskin.  Jo measuring the radiocarbon is just waking up on the first afternoon CTD and gets the tease from everyone that she’s late… again! And when Chibo is sampling her chlorophyll I’m luckily getting the tightest hugs ever, followed by the Queen’s wave.

 

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The afternoon watch (image: K. Giamalaki)

Sometimes different music genres are on and you kind of know who’s music it is. Other times most of us are silent. Sometimes the sun is shining bright on our faces, some other times it’s cloudy and moody. One could possibly not imagine how variable  such a routine round trip can be. But trust me, each one has a different charm and ooops…gotta go now, it’s time for boxing! Yes, we’re doing that as well on-board!

The strange symphony of CO2 analysis

 

by Jean-Philippe Gac

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VINDTA. On the left, the titration system of alkalinity, by method of Gran. On the right, the coulometer, allowing the quantification of the DIC by a light measurement of CO2 extracted from seawater. (Image: J.P. Gac)

‘Click, click’, ‘Vrrr’, ‘Tick, tick’. In the middle of the South Atlantic, strange and frightening machine noises emanate from one of the RRS James Cook laboratories. Inside, a legend tells that incredible monsters live there, made of glass, tubes and acids. These curious animals are the VINDTA. Day and night, during 42 days, 4 brave and courageous scientists take turns relentlessly to satisfy the insatiable thirst for seawater of these two behemoths. A key to this great quest: new knowledge on CO2 cycles.

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CO2 Team: Pablo Trucco, Jean-Philippe Gac, Katerina Giamalaki and Peter Brown. (Image: J-P Gac)

CO2, denounced by all as the “big bad guy” of the environment of the 21st century, needs to be studied regularly. Indeed, the ocean is a formidable CO2 scavenger: it absorbs ¼ of anthropogenic emissions. But how does the ocean react to the continued increase in anthropogenic CO2 input? It is to answer this question that our expedition was implemented: to understand the CO2 cycles in the Atlantic sector of the Southern Ocean, and to compare their evolution with those of past expeditions.

Beyond their terrifying appearances and their endless appetite, the VINDTAs are able to determine with great precision alkalinity and dissolved inorganic carbon, two important factors for the determination of the partial pressure of CO2 in the seawater. Thus, a large database can be established, all across 24°S, from the deep to the surface water.

In the midst of the Atlantic

by Gadaffi Liswaniso

Almost midway through the 24oS transect from Rio to Walvis Bay onboard the James Cook research vessel on cruise JC159, and by now we don’t need to look at each other’s name tags to know who is who, just some laughter in the corridors signifying friendship. The JC is equipped with one person cabins allowing privacy for each person onboard, no one has to worry about another person’s love for broccoli during sleeping times, ha ha!! Although we are very far from our family and friends, the IT team has made sure we stay connected to the world via the onboard WiFi connection that is available in most spaces on the ship.

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As JC159 left Rio, we managed to capture a view of some apartments creeping up the mountains (image: Gadaffi Liswaniso)

Time differences have been a hustle since we left port in Rio as I had to keep up with 3 different clocks: time on onboard, GMT and Namibian time to ensure I don’t call anyone back home at 2 a.m thinking it was right timing.

The RRS JC scientific crew consists of five working groups that sequentially work on the CTD after it has been hauled out, starting out with the CFCs, dissolved oxygen, carbon, nutrients, isotopes, salts and lastly either biological or microplastic sampling. Each group has a designated laboratory where they analyze their samples before arriving at the next station. Each group has 8 hours on shift plus 4 hours standby for post data analysis or any other tasks as required to perform. For sure none of all the scientific analysis would be so efficient without the ship technical crew, bravo to them!

Argo floats are also onboard to ensure continuation of data collection in the S. Atlantic; they are designed with lithium batteries that can last up to 5 years without replacement while collecting important physical data of the ocean, and operate through special missions given by the user. Not only do Argo floats stay on the water surface but they are also able to dive down to 2000 or 6000 m depending on model, thereby giving us a profile of oceanic physical data at various depths according to specific missions.

 

At least two emergency drills have been done since leaving port to ensure safety out at sea, orienting all aboard on the necessary steps to follow in case of an emergency, where to go, what to bring along, and how to use the safety gear for sea going purposes. We have really settled well onboard, today I even did my first laundry.  We have a resourceful library, a well-equipped gym and sauna, and a lounge with various movie genres and gaming consoles to help us enjoy during rest hours. There is also a bar where we can chat over a beer or wine. The ship’s crew even went the extra mile and made a temporary seawater pool to relax in during warm sunny days out in the midst of the Atlantic.

On the hunt for invisible drifters across the South Atlantic Ocean

by Nina Faure Beaulieu

Everyone aboard the James Cook is on a different mission, and each team is formed of detectives who are gathering clues to solve a wider mystery. Our mystery is rather a big one, in fact it is the biggest one on earth: the ocean.

My role in this group of detectives is to hunt for the near-invisible: microplastics. These are tiny pieces of plastic, the official definition being any plastic smaller than 5 mm. Despite their overwhelming presence in the news lately, we actually know very little of the basic facts about them. How do they form? Where do they come from? How are they transported both across and through aquatic environments? Where are they going? What effects, if any, are they having on marine life? How does their abundance change across different oceans? Hopefully this expedition will bring us a microstep closer to answering some of these questions about microplastics.

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The CTD rosette from above, with water samplers at the ready (image: N. Beaulieu)

Our sampling transect crosses the South Atlantic from Rio De Janeiro in Brazil to Walvis Bay in Namibia. I will be attempting to sample microplastics both across and down the water column to understand a little more about their oceanic distribution. This transect is particularly interesting as it crosses the South Atlantic Subtropical Gyre. Gyres are large, circulating oceanic currents driven by the combination of winds and the earth’s Coriolis force (rotation); debris tend to accumulate in the centres of the subtropical gyres.

Along this 6-week transect, the ship stops about every three hours to pick up 24 passengers. These passengers are 20 litre water samples recovered at 24 discrete depths from the sea floor to the surface. Our deepest sample lived at 5697 m and it took about 3 hours for our sampling device to reach it. The device in question is called a CTD– Conductivity, Temperature and Depth– after its principal sensors, and consists of a rosette, or frame, carrying 24 bottles of 20 litres each.

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CTD sampling at sunset (image: N. Beaulieu)

Every team gets to collect some water from each bottle; my role is to filter my allocated water through 55 µm (0.055 mm) stainless steel meshes and sometimes onto 1 µm (0.001 mm!) polycarbonate meshes, so that I can measure the microplastics left behind.

However, there’s a catch. Microplastics are everywhere. They come in the form of fibres, fragments, airborne particles, and so on.  Look at the composition of your clothes right now and it is highly likely they are a mixture of cotton and plastic or even 100% synthetic material, and are constantly shedding fibres. This is a problem when sampling for microplastics: how do you know that what you find comes from the water and not your t-shirt?

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CTD microplastic sampling (part 1): The 55µm mesh is enclosed in the cylinder at the end of the tube, and gravity pulls water through into the carboy (image: N. Beaulieu)

For the 55 µm filtering step, it is easier to protect my sample from contamination. All I need to do is connect a tube to the 20 L bottle and let the water flow through an enclosed casing which contains my 55 µm mesh. The pore size of the mesh is large enough to then let gravity do most of the work and pull the water through. The water coming out is collected in containers so that I can calculate the exact volume filtered.

Unfortunately, gravity stops being a sufficient ally when it comes to pulling water through a 1 µm mesh. The pore size is simply too small for it to work and I need a vacuum pump to force the water through. This is when it becomes tricky. Usually, the water collected would be poured from the container into an open beaker which is connected to the vacuum pump via my 1 µm mesh. This just won’t do for microplastics as pouring and open containers means airborne particles could very easily accumulate on the water’s surface and skew my results.

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CTD microplastic sampling (part 2): The water is pulled out of the carboy by a vacuum pump (not in picture) into the beaker (orange cap) via 1µm mesh. The waste funnel in the back corner is to calculate volume (image: N. Beaulieu)

This is when I switch from being a detective to an engineer. Or in my case, ask Howard the engineer to come to the rescue! He helped me construct a system where I can connect my container directly to the filtering pump. No exposure to air required!

There are many additional precautions that need to be taken too. When I packed for this cruise I made sure to only take 100% cotton clothing. My equipment needs to be kept inside a laminar flow hood ,which is a semi enclosed unit with filtered air flowing through it. And filters, petridishes, filtering equipment, tubes, etc. need to be regularly acid washed.

So that’s a brief description of my job on the ship; by the end I’ll have filtered over 2 thousand litres of water!  The next step of detective work will come back in the lab on dry land. I will examine my filters under a fancy infra-red microscope (Fourier Transform Infra-Red (FTIR) Spectroscope) and hopefully bring the invisible into the spotlight.

Sunrise watch

by Yvonne Firing

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Pre-sunrise CTD water sampling, with Olga ready to log the samples as a bit of colour appears in the sky (image: Y. Firing).

Now that we’re two weeks into the cruise, we’ve all settled into the routines that go with round-the-clock CTD stations.  Part of conducting science at sea is deciding on the watch rota: who will be principally responsible for each aspect of data collection at different times throughout the day.  Cruises generally mean 12 hours at work each day (with breaks, of course!).  Some groups prefer straightforward 12-hour watches, others an 8-on, 4-off, 4-on, 8-off schedule, while others organise three 8-hour watches with flexibility in the remaining hours to make it easier to overlap with personnel on different schedules.  The physics team on JC159 has adopted the last approach, and as a morning watchstander, I have to admit that waking in the early hours to start work at 4 am takes a little getting used to–and then a little more each time we shift the clocks forward to keep up with our eastward progress.  But the sunrises more than make up for the early start!

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Even the CTD rosette is taking on sunrise hues … (image: Y. Firing)
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… and finally, the sun! (image: O. Sato)
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Between CTDs it can be easy to forget to look up from the computer screen, unless a strange glow through the portholes catches your attention … (image: Y. Firing)
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… a glance outside revealing pink sky, and pink sea, and pink ship (image: Y. Firing)

 

 

JC159 Week 1: RRS James Cook visits Rio

by Jack Giddings

Berthed right next to the stunning tropical scenery of Rio de Janeiro, the crew and scientists onboard the RRS James Cook were busy preparing for the next 6-week cruise across the South Atlantic. There was no time to waste. Shortly after stepping off the plane, heavy boxes were unloaded, lab equipment set up and computer fans whirled into life, ready for the hundreds of samples that would be collected across the width of the Atlantic down to its deepest depths. For the nutrients, CFCs, carbon and oxygen teams, a lab’s worth of equipment had to be connected and calibrated ready for the influx of new samples. For the Argo float team, all eight floats were tested to guarantee sufficient satellite communications and functioning external oil and air bladders. For micro-plastic research, creating a zone free from air-borne contaminants was no easy task; it turns out there are plastic fibres everywhere in our environment. To ensure the airborne plastic doesn’t contaminate the sea water samples, all surrounding surfaces were cleaned, static plastic sheets were draped around a work space to attract synthetic fibres from the air, and scientists must wear all-cotton clothes.

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Rio from on high (image: Jack Giddings)

But it wasn’t all frantic preparation or last-minute sensor calibrations. The science party managed to venture into the sun-soaked sweat-box that was Rio, exploring the must-visit sights the city has to offer. Of course Copacabana was on the check-list, with some eagerly swimming in the warm(ish) waters of the Atlantic. Some ventured up to Christ the Redeemer, which provided breath-taking panoramic views over the city from Ipanema to Downtown Rio. And obviously one couldn’t resist a refreshing cocktail on the beach to end the day, soaking up samba music and the local hubbub.

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The Museum of Tomorrow and downtown Rio (image: Jack Giddings)

Before we set sail, all scientists were invited by the Ambassador of the UK to Brazil and the President Director of the Museum of Tomorrow to attend a cocktail party. The event, celebrating the pre-launch of the UK-Brazil Year of Science and Innovation 2018-2019 was held in the futuristic Museum of Tomorrow. Several speeches were made during the event, from the Brazilian Minister for Science and Technology to the UK Ambassador for Brazil himself, many reiterating the importance of scientific research and international collaboration. It was a reminder for all the scientists onboard the ship that the measurements recorded during this cruise will play a vital role in climate simulations that will improve future projections of a warming world. This motivation will spur future expeditions across the South Atlantic within the next decade, gradually building a picture of how sensitive this part of the ocean is to our changing climate.

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As we steamed out to sea we caught a last glimpse through the clouds of Rio’s famous statue of Christ the Redeemer (image: Yvonne Firing)

A couple of days into the cruise, the first several stations have been sampled across the shelf edge off the coast of Brazil. After a very chaotic round of water sampling from the test CTD on day one, everyone is finding their feet and settling comfortably into their shift patterns. More updates will follow.