S4GES at sea with RV Belgica (part 4)

Thursday 14 July 2022

Going from shallow to very shallow

Today the S4GES expedition with the RV Belgica moved shoreward. Very high chlorophyll concentration characterizes this coastal environment, which is particularly affected by inland input of nutrients. We completed a transect that cut from the deeper stations yesterday to two shallower sites with accordingly different tidal dynamics, thus exploring all the biogeochemical patterns observed from satellite. Water depths of ca. 15 meters at the day’s first station and less than 10 meters at the second came with its own challenges. At the second station, the ship had only a few meters of water below its keel, requiring attentive navigation. The vertical plankton net that needs a bit of legroom to operate was not deployed here. Nonetheless, the Flemish coast seemed to be so close that we might have had some interested audience from tourists promenading the beach. Heartfelt greetings from the Belgica if you were one of them and googled your way to this blog post!

Touching base with heavy gear

A condensed sampling routine during only one velocity minimum of tidal currents per station offered the opportunity to finally sample the sediment also. The massive box corer device was therefore used at both stations. Researchers on board were interested to explore whether they would find ostracods, benthic foraminifera or shells of planktonic foraminifera. Sampling the water column on station is a snapshot of the conditions of that day and hour. Sediments on the other hand have the advantage of being deposited quasi-continuously over years. This makes the sediments a low-pass filtered archive of water column dynamics. So much for the theory. Lab work will reveal whether the sediments contain the desired shells. What the box corer definitively brought on deck was a brittle star, a shrimp and a little fish. All were of course treated with loving care and returned to the water unharmed.

The heart and lungs of the Belgica

Some of the scientific team took the opportunity to descend all the way to the deep level 2 of the ship. This is where the (mostly) unsung heroes and heroines reside – referring to the engines and the crew members that maintain them. Connoisseurs of machine engineering have a lot to see and the regular clueless scientists a lot to marvel at: a monitor-laden control room, three diesel engines to generate electricity, two electric engines for propulsion, four thrusters, a water treatment station, a workshop, and much more. While parts of the engine rooms are obviously really noisy, the whole place is clean and tidy, which might not have been expected to that degree of spotlessness. Not the only surprise down there …

Artist’s delight in an unexpected place

With the Belgica largely held in elegant tones of white and grey, our visual artist Sarah-Marie Kröger had begun to feel a little deprived of colourful motives. She found them rather unexpectedly in the bowels of the ship. The different machines in the engine room are painted in bright blue, red, green, etc. Sarah was thrilled and turned her new-found inspiration immediately into a couple of industrial art pictures à la Belgica.

Text by Thorsten Kiefer (JPI Oceans) & Federico Falcini (CNR), Images by Thorsten Kiefer (JPI Oceans)

 

Other blog posts in this series

S4GES at sea with RV Belgica (part 1)

S4GES at sea with RV Belgica (part 2)

S4GES at sea with RV Belgica (part 3)

S4GES at sea with RV Belgica (part 5)

S4GES at sea with RV Belgica (part 3)

Wednesday 13 July 2022

The art of standing still

Most of the Wednesday of the North Sea campaign of JPI Oceans’ S4GES Joint Action was spent on one spot to follow a tidal cycle. This sounds easy and boring. Well, it is neither … Keeping a ship on position in a highly dynamic environment of tides, winds and currents is anything but trivial. However, as one of its modern features, the RV Belgica is equipped with outstanding maneuvering facilities (and the crew with the skills to make the most of them). Cutting-edge thrusters allow the ship to hold position with a meter-precision even at today’s surface current speeds in the order of 1-2 knots. Also, operating light and delicate sampling gear in turbulent waters can be tricky. You clearly want to avoid that plankton nets and other gear deployed from the working deck at the Belgica’s starboard side hits the hull or that cable gets entangled in a propellor. The navigation team on the bridge therefore rotated the ship steadily clockwise to cause an outward drift that keeps instruments safe from hitting the ship or they kept the ship strictly perpendicular to the current to prevent a flow along the sides of the ship. Impressive delicate handling of a 71-meter ship. It feels like playing a Paganini caprice on a double bass.

Same, same but different

Why did we spend the best part of a precious day at sea on that one station? Not just because we can, but because it made perfect scientific sense. Today’s station complemented the previous stations. It brings us as close to a controlled experimental design as one can get with seagoing fieldwork. The station was little more than 30 meters deep, thus comparable to the stations yesterday and the day before. All were “deep” for the Southern Bight of the North Sea. However, the real-time remote sensing Ocean Colour imagery (check Tuesday’s blog entry for more) showed high chlorophyll values, suggesting a biologically more dynamic setting than the previous deep stations. For consistent sampling, the researchers carried out their sampling routine again at maximum-minimum-maximum velocity of tidal currents at the site.

Yellow marks the spot

One tripod among a hundred plus wind turbines

On the programme for the late afternoon was a stroll through the forest – a forest of offshore wind turbines. Amidst this thoroughly impressive array for renewable energy generation, the ship navigated to a tiny yellow buoy marking the location of a tripod that was sitting at the seafloor for the last three weeks. The tripod was equipped with instruments to measure temperature and conductivity (and by implication salinity), current speeds all the way from near the seafloor to the surface, and turbidity and the related particle size spectrum. Furthermore, sediment traps collected sinking particles and a special camera photographed small organisms passing through. Good to know that the recovery of the tripod and its precious instruments went smoothly, for extraction of samples and data and maintenance of the whole array.

Tripod recovery

Artist speeding up

Our on-board artist Sarah-Marie Kröger changed gear into sketching mode today, speed-drawing live scenes of people working on deck and in labs. This was exploratory territory for her with respect to sketchy style and unsteady scenes. It was also probably a rare experience for the researchers having to walk around an artist placed in the middle of the lab and immersed in her craft. The researchers eventually got rewarded by being shown the drawings that depict them in action. The artist will hopefully get her reward by receiving many enthusiastic likes for the related social media posts in Instagram and Twitter, if you get the hint …

Sarah-Marie Kröger at work (see also some results below)

Text by Thorsten Kiefer (JPI Oceans) & Federico Falcini (CNR) – Images by Thorsten Kiefer (JPI Oceans)

 

Other blog posts in this series

S4GES at sea with RV Belgica (part 1)

S4GES at sea with RV Belgica (part 2)

S4GES at sea with RV Belgica (part4)

S4GES at sea with RV Belgica (part 5)

 

S4GES at sea with RV Belgica (part 2)

Tuesday 12 July 2022

A planned change of plan

A specific feature of this S4GES cruise is that the definition of the sampling stations originally planned in the cruise programme are fine-tuned and continuously revisited during the cruise. Decisions are based on near-real-time “Ocean Colour” remote sensing imagery, processed from EUMETSAT. Accordingly, the cruise leadership decided yesterday to skip the second “deep” station in Dutch waters. Chlorophyll data from the same day from two Sentinel3 satellites had shown that the station would have been very similar to the previous one with low chlorophyll-a concentration, thus promising little additional scientific insight. Instead, the campaign moved therefore directly to a station with a higher chlorophyll signature, promising a regime of higher biological productivity and different ecosystem.

Early rise

During the night the RV Belgica sailed back into Belgian waters, to do two stations at water depths of ca. 35 meters. The first station of the day was perfect for early-birds and sunrise spotters. For methodological consistency, the tidal current minimum at 6 AM was under no circumstances to be missed! Accordingly, everyone was on deck at sunrise for nice shots (talking about photographs obviously) and a new set of samples and measurements. It appears that sampling and sample processing already run like a well-oiled machine, leaving space to get excited about first scientific observations (more of that over the coming days …) – and a world premiere (presumably)!

Early morning rise

A first: Bio-Lagrangian drifter

A special highlight of the day was the release and recovery of a drifter that followed the plankton community. The so-called Bio-Lagrangian drifter provides a frame of reference while moving with the plankton community itself, i.e., the Lagrangian approach. Lagrangian drifters are designed to follow the water at the ocean surface, providing accurate measurements of ocean currents and their physical properties (temperature and salinity). Our Bio-Lagrangian upgrade is configured to also collect high frequency observations of plankton community properties with a bio-optical sensor. The sensor measures the scattering of visible electromagnetic radiation backward with respect to the direction of propagation. This “particle back scattering” relates to the particle concentration in seawater, including phytoplankton and non-algal particles (e.g. viruses, bacteria and detritus). The first Bio-Lagrangian drifter prototype has been funded by the Institute of Marine Sciences, ISMAR, of the National Research Council of Italy, CNR, and the first ever deployment took place today during the S4GES cruise – exciting!

Recovery of Lagrangian drifter

Painting plankton

Meanwhile, our on-board artist Sarah-Marie Kröger found herself inspired by the fascinating world of marine plankton. Watching the deployment of plankton nets, recovery of the catch and microscopic inspection of the sample, she combined these respective scenes captured on board into a new painting. While yesterday’s portrait of the RV Belgica was more like a majestic still life, today’s picture is full of action and illustrating the fascination of research and researchers – or whatever else it stirs in you …

Scientists deploy plankton nets, recover and inspect the catch (artwork Sarah-Marie Kröger).

Text by Thorsten Kiefer (JPI Oceans) & Federico Falcini (CNR), Images by Thorsten Kiefer (JPI Oceans)

 

Other blog posts in this series

S4GES at sea with RV Belgica (part 1)

S4GES at sea with RV Belgica (part3)

S4GES at sea with RV Belgica (part4)

S4GES at sea with RV Belgica (part 5)

S4GES at sea with RV Belgica (part 1)

Monday 11 July 2022

S4GES at sea with RV Belgica

The long-planned one-week expedition S4GES is now in full swing. A team of scientists has embarked the brand new Research Vessel (RV) Belgica over the weekend, familiarized themselves with the facilities on board, revisited the research programme and started the sampling campaign. Preparations were struck by Corona troubles until the very last minute, including the originally foreseen chief scientist, then also its replacement. But here we are now, under the brave leadership of Dr Federico Falcini from CNR, Italy, and Prof Isabelle Schön from RBINS, Belgium.

The cruise operates under the Science for Good Environmental Status (S4GES) Joint Action of JPI Oceans. Eleven countries join forces and share experts to explore new approaches to determine the environmental status of marine waters and provide efficient and effective observational strategies, in support of the European Union’s Marine Strategic Framework Directive (MSFD).

Getting started with the scientific programme

This first S4GES expedition aims at assessing the Good Environmental Status (GES) of the marine environment by integrating physical, chemical, bio-optical, and biological information from the Southern Bight of the North Sea. On Monday, the focus was on the “deep” station of the expedition. Maybe forty meters water depth does not sound deep to you, but it does so for shallow Belgian-Dutch waters. At such shallow water depths, tides are a crucial driver of physical and biological dynamics. The sampling and measurement strategy for physical and bio-optical parameters, water samples and plankton samples is therefore paced at the maximum of the high and low velocity of marine tidal currents, respectively. This is allowing to connect the dots between the physical forcing and the biological patterns that evolve through space and time during the tidal cycle. More on the scientific operations in coming posts.

Art meets science

Beyond the scientific programme, the S4GES expedition to the North Sea also aims to close the emotional gap we tend to have with the ocean, the “silent majority of the Earth (quoting John Bell from the European Commission, DG Research and Innovation). Art can be a vehicle to make us care more about the ocean. There might be a reason why art rhymes with heart. Visual art can furthermore transcend cultural and language barriers. There are surely many more good reasons to marry art with science. But you are also welcome to just indulge in the visual pleasure of this first painting by Sarah-Marie Kröger, our artist on board and to look forward to more of those being created over the course of the week.

Sarah-Marie Kröger creates a majestic still life of RV Belgica

Text by Thorsten Kiefer (JPI Oceans) & Federico Falcini (CNR) – Images by Thorsten Kiefer (JPI Oceans)

 

Other blog posts in this series

S4GES at sea with RV Belgica (part 2)

S4GES at sea with RV Belgica (part3)

S4GES at sea with RV Belgica (part4)

S4GES at sea with RV Belgica (part 5)