A First Cruise Experience with NASA’s S-MODE Field Campaign

By Mackenzie Blanusa, M.S. student at the University of Connecticut // Aboard the Bold Horizon //

I had been patiently waiting and dreaming about this research cruise for months. Yet a few days before traveling from Connecticut to Oregon for ship mobilization, I couldn’t shake a feeling of denial – like I couldn’t believe I was really going to be out in the Pacific Ocean on a research vessel for an entire month.

Mackenzie, a young white woman in a long red coat, poses on the R/V Bold Horizon. She is leaning on the railing, with blue ocean water and a sunset behind her.
A picture of Mackenzie on the R/V Bold Horizon with a sunset in the background. Credit: Jessica Kozik

I am participating in NASA’s Sub-Mesoscale Ocean Dynamics Experiment (S-MODE) as part of the science party aboard the research vessel Bold Horizon. The focus of this experiment is to sample ocean fronts that are a few miles in size to study their dynamics and effects on vertical transport. The ocean fronts are sampled using aircraft, ship surveying, and autonomous platforms with names such as wave gliders, sea gliders, Saildrones, floats, and drifters. So being aboard the ship is just one piece of this complex research experiment.

Ben Hodges from the Woods Hole Oceanographic Institution (WHOI) holding the EcoCTD. The electric winch is on the right. Credit: Mackenzie Blanusa


On the R/V Bold Horizon I have been working the night shift from 4 p.m. to 4a.m. My nights mostly consist of running an instrument called an EcoCTD, which measures temperature, salinity, pressure, chlorophyll, backscatter, and oxygen. The EcoCTD is casted off the back of the ship using an electric winch and travels vertically through the water column to a depth of about 390 feet (120 meters), and is then reeled back in. We usually do this all through the night while driving back and forth across a front. The vertical profiles then get plotted through time and we utilize this data in real time to decide where to deploy autonomous instruments, collect water samples, and keep track of how ocean fronts are evolving.

A depiction of the EcoCTD data. Temperature (in degrees Celsius) is plotted as a time series vs. depth. The white contours are lines of constant density. A front can be seen at the surface as the temperature goes from cool (green) to warm (yellow). The pattern repeats itself as we go back and forth across the front. Credit: Ben Hodges
A picture of a wave glider used in the S-MODE experiments. Credit: Mackenzie Blanusa

Additionally, I have been helping with the recovery and deployment of wave gliders and mixed layer floats. Wave gliders are an autonomous surface vehicle that look like a surfboard and are powered by waves and solar energy. They measure variables such as velocity, temperature, salinity, wind speed and direction, air pressure, and radiation. There are eight wave gliders in this experiment, and we had to recover one of them because it had a broken sensor. The mixed layer floats are recovered and deployed every few days and are tasked with floating in the mixed layer to measure vertical velocity.

Mackenzie (left) and Avery Snyder (right) getting ready to deploy a mixed layer float. Credit: Alex Kinsella

Aside from all the science, it’s also worth mentioning what life on a research vessel is like. It often feels simpler than the hustle and bustle of everyday life on land – I have a set 12-hour shift doing a very specific task, get meals provided for me, and have limited communication with the rest of the world. Everything feels more clear-cut, and I know what my purpose is. Of course, sea going is also mentally tolling due to the constant rocking back and forth. But we’ve been lucky with mostly good weather, and I haven’t gotten seasick yet.

While S-MODE is certainly a busy experiment with a lot of moving parts, there are moments where it feels like there is nothing to do. This often happens when the weather and sea state is too rough for sampling, so we are forced to find other ways to occupy our time…which can be challenging since you’re in the middle of the ocean with little entertainment. Times like these are met with playing silly games, watching a movie, and learning how to tie different types of knots.

S-MODE is wrapping up in a few days and I’ll be on my way back home. The sense of denial I once felt has been replaced with self-confidence and motivation to pursue a career as a seagoing oceanographer. I have learned so much from all the other scientists on board who are more than happy to share their knowledge with a curious graduate student. Although S-MODE is ending, I know this is just the beginning of my journeys at sea.

Life at Sea: A “First-Timer” Chronicles NASA’s S-MODE Field Campaign

By Sarah Lang, Ph.D. student at the Graduate School of Oceanography, University of Rhode Island. // Aboard the Bold Horizon //

Going to sea for the first time as part of NASA’s S-MODE mission has been an experience like no other. You establish a new normal on the boat and quickly fall into new routines. Perceptions of time even change! I joked with some people on the boat that time is but a label on our samples. Perhaps that’s a bit dramatic, but normal perceptions of time do not apply at sea –especially if you start your day at 2 pm and finish at 2 am.

For me, time flies the fastest when Pat Kelly and I are taking biological samples for long periods of time, looping through our collaborative Spotify playlist titled “boat songs. With Talking Heads, Madonna, Mötley Cru, and Fleetwood Mac, we have quite the mix. Pat rolls his eyes any time one of my disco songs comes on, but I know he secretly loves it.

Caption: First sunset off the Bold Horizon after many cloudy days!

For those on the night shift, their work day doesn’t begin until 4 pm in the afternoon and doesn’t end until 4 am. They have lunch in the middle of the night! And a cup of joe with breakfast at the same time those on land are getting home from work.

Most people have the day shift (0400 – 1600) or the night shift (1600 – 0400). A few of us on the biology team have schedules that change all the time, so I get to experience a bit of both.

The day shift is nice because that’s when most meals are served, and if you keep your eyes peeled you might see dolphins, sea lions, or whales. The night shift has its perks too. Typically, there is a movie playing in the lounge for those on break. It’s a bit quieter on the boat, except when we’re laughing at Flight of the Conchords or dancing on the back deck during EcoCTD shifts (an EcoCTD is a vertical profiler measuring physical and biological variables). We’ve only had one day of (semi) clear skies, so nights on the water have been especially dark. Beyond the light of the boat, it’s pure darkness. No light from land in sight.

Caption: (Left) Alex Kinsella, Leo Middletown, Igor Uchôa Farias, and Kelly Luis standing on the deck as we depart San Francisco harbor after a quick pit stop. (Middle) The Bold Horizon sailing on the blue sea, with a CTD-Rosette sitting on the deck. (Right) Audrey Delpech and Mackenzie Blanusa in immersion suits, AKA gumby suits. These are safety suits that protect against hypothermia in the case of an emergency.

Now onto the science!

We are here to study submesoscale (small! 1-10 km) dynamics in the ocean, which are associated with significant vertical velocities. We care about how climate-relevant parameters like heat and carbon are taken up by the ocean and what happens to them once they are in the ocean. Submesoscale features change really fast, which makes them very difficult to study. In this campaign, we are studying these features with autonomous vehicles (like Saildrones and Wave gliders), Lagrangian floats (which move with the water), airplanes, and of course, the ship. We’ll need all the data we can get to understand these complicated and quickly-changing processes!

Caption:(Left) Deploying the CTD-Rosette to collect seawater samples at depth, as well as vertical profiles of temperature, salinity, oxygen, backscatter, and chlorophyll-fluorescence. (Middle) Igor Uchôa Farias and Mackenzie Blanusa on Eco-CTD watch, listening to Megan Thee Stallion. (Left) Jessica Kozik and Mara Freilich working on computers in the “dry lab,” with the “wet lab” behind them.

Many of us on the biology team are interested in how these smallscale processes structure phytoplankton communities. Phytoplankton are microscopic organisms that undergo photosynthesis, taking up carbon from the ocean and producing much of the oxygen we breathe. They are the base of the marine food web, so if you like fish and dolphins and other sea creatures, you like phytoplankton! It’s important to know the controls on the distributions of phytoplankton species. Complex ecological interactions in the ocean are important to the ocean’s carbon cycle, and therefore, Earth’s climate system.

“Ocean color” is a key piece to this puzzle. We use light to study the biogeochemistry of the ocean. Light interacts with water and the “stuff” that’s in the water (like phytoplankton!). We can quantify these interactions with optical measurements to understand more about the biogeochemistry of the ocean. This is also how we can study the biology of the ocean from space.

In my next blog post, I’ll talk about how we use seawater samples to validate optical measurements, and how we use these optical measurements to understand measurements taken by hyperspectral sensors on airplanes (and eventually in space by NASA’s PACE mission!).

Student of the Sea: Learning the Ropes Aboard NASA’s S-MODE Mission

By Igor Uchôa, Ph.D. student at the University of Maryland in the Atmospheric and Oceanic Sciences Department // Aboard the Bold Horizon //

NASA’s S-MODE mission was designed to measure and understand the complex oceanic features classified as “submesoscale,” i.e., features spanning up to 6.2 miles (10 kilometers) across. Such fine filaments and sharp density fronts in the ocean are responsible for fast and unpredictable changes in velocity, temperature, salinity, and even among small organisms called plankton in the surface layer of the ocean. A myriad of autonomous instruments, airborne sensors, and a fully equipped ship are part of the robust methods of measuring submesoscale dynamics in the California Current region.

There are currently more than 40 scientists among researchers, students, and technicians from various institutes working together either virtually all over the country (in the control center), or in the research vessel Bold Horizon (where I currently am) sampling and streaming data for the group to analyze. Within the S-MODE science party, the air-sea interaction group attempts to understand the connections between the submesoscale filaments in the ocean and the atmosphere above them. As part of this group, learning has been my daily activity on the ship.

A science team of roughly 20 people stands on the pier in front of a research vessel.
Science team on board the R/V Bold Horizon for the second deployment of the S-MODE mission (10/07/2022). Credit: Erin Czech.

One of the tasks I am responsible for here, among other science team members, is the launching of instruments called radiosondes while the ship surveys important features in the ocean. The 200 radiosondes stocked in the ship are comprised of a foam cup, a helium-filled balloon, and a sensor. The instruments, which resemble a toy, are incredibly valuable for observing the temperature, humidity, winds, and even cloud-base height of the atmosphere in its first 3.1 miles (5 kilometers) from the surface on average.  

The ocean and atmosphere at larger scales actively interact and change each other’s properties. One of the goals of the S-MODE cruise is to find out if this also occurs in submesoscale phenomena such as cold, dense filaments in warm waters as commonly seen in the California Current region.

Three images -- on top is a photo at night of scientists on the research vessel. On the bottom left, a man releases a small balloon attached to a device that collects atmospheric data. On the right, a team aboard the ship deploys autonomous floating marine robots.
My experience on the S-MODE cruise sampling: (top) casting a sensor underway for vertical sections of oceanographic properties such as temperature, salinity, chlorophyll, and dissolved oxygen, (left) launching a radiosonde in calm weather conditions, (right) Avery Snyder, Gwendal Marechal, Jessica Kozic, and I on the deployment of Lagrangian floats for tracking and measuring properties of submesoscale features. Credit: Alexis Arends, Andrey Shcherbina.

Installing those sensors is a relatively easier task than the high-tech instruments found on the research vessel, but the practical launching is sometimes a bit… daunting. Knowing how to tie a balloon suddenly becomes essential when you must launch many radiosondes in a small window of time in a rocking ship in windy weather. Also, becoming an expert observer of wind direction is a must-have skill, or else expensive sensors become tangled in the ship and lost forever. It is still a fun procedure, nonetheless, which brings very useful information to the puzzle of understanding air-sea interaction in the submesoscale.

Throughout the process of helping the team launch S-MODE and bring useful data to the group, I had to learn how to take more initiative. I gradually felt that I became part of the plan-of-action for the survey, which I believe is very important for a scientific career, especially for a Ph.D. student like me. Being part of such a high-level research mission is both an overwhelming and exciting learning experience. We still have many days to go, but I am certain that this cruise has already taught me a lot.